Impact of tumor size on overall survival and cancer-specific survival of early-onset colon and rectal cancer: a retrospective cohort study.

PURPOSE: This study aimed to investigate the impact of tumor size on survival in early-onset colon and rectal cancer. METHODS: Early-onset colon and rectal cancer patients were identified from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Tumor size was analyzed as both continuous and categorical variables. Several statistical techniques, including restricted cubic spline (RCS), Cox proportional hazard model, subgroup analysis, propensity score matching (PSM), and Kaplan-Meier survival analysis, were employed to demonstrate the association between tumor size and overall survival (OS) and cancer-specific survival (CSS) of early-onset colon and rectal cancer. RESULTS: Seventeen thousand five hundred fifty-one (76.7%) early-onset colon and 5323 (23.3%) rectal cancer patients were included. RCS analysis confirmed a linear association between tumor size and survival. Patients with a tumor size > 5 cm had worse OS and CSS, compared to those with a tumor size ≤ 5 cm for both early-onset colon and rectal cancer. Notably, subgroup analysis showed that a smaller tumor size (≤ 50 mm) was associated with worse survival in stage II early-onset colon cancer, although not statistically significant. After PSM, Kaplan-Meier survival curves showed that the survival of patients with tumor size ≤ 50 mm was better than that of patients with tumor size > 50 mm. CONCLUSION: Patients with tumors larger than 5 cm were associated with worse survival in early-onset colon and rectal cancer. However, smaller tumor size may indicate a more biologically aggressive phenotype, correlating with poorer survival in stage II early-onset colon cancer.

Advancing mid-rectal cancer surgery: Unveiling the potential of natural orifice specimen extraction surgery in comparison to conventional laparoscopic-assisted resection.

BACKGROUND: Mid-rectal cancer treatment traditionally involves conventional laparoscopic-assisted resection (CLAR). This study aimed to assess the clinical and therapeutic advantages of Natural Orifice Specimen Extraction Surgery (NOSES) over CLAR. AIMS: To compare the clinical outcomes, intraoperative metrics, postoperative recovery, complications, and long-term prognosis between NOSES and CLAR groups. MATERIALS & METHODS: A total of 136 patients were analyzed, with 92 undergoing CLAR and 44 undergoing NOSES. Clinical outcomes were evaluated, and propensity score matching (PSM) was employed to control potential biases. RESULTS: The NOSES group exhibited significant improvements in postoperative recovery, including lower pain scores on days 1, 3, and 5 (p < .001), reduced need for additional analgesics (p = .02), shorter hospital stays (10.8 ± 2.3 vs. 14.2 ± 5.3 days; p < .001), and decreased intraoperative blood loss (48.1 ± 52.7 mL vs. 71.0 ± 55.0 mL; p = .03). Patients undergoing NOSES also reported enhanced satisfaction with postoperative abdominal appearance and better quality of life. Additionally, the NOSES approach resulted in fewer postoperative complications. CONCLUSION: While long-term outcomes (overall survival, disease-free survival, and local recurrence rates) were comparable between the two methods, NOSES demonstrated superior postoperative outcomes compared to CLAR in mid-rectal cancer treatment, while maintaining similar long-term oncological safety. These findings suggest that NOSES could serve as an effective alternative to CLAR without compromising long-term results.

Impact of Neoadjuvant Radiochemotherapy on Pathological Complete Response for Locally Advanced Rectal Cancer: A Mono Institutional Experience.

BACKGROUND/AIM: Neoadjuvant radiochemotherapy followed by surgery is a standard of care in locally advanced rectal cancer (LARC). Only a subgroup of patients can obtain a pathological complete response (pCR) and achieve good local control. However, the role of pCR on patient survival is debated. The aim of the study was to evaluate the impact of pCR on clinical outcomes and toxicities in LARC patients treated with dose intensification and concomitant capecitabine treatment in a neoadjuvant radiochemotherapy schedule. PATIENTS AND METHODS: This was a single Institution retrospective study including 178 patients. Mandard tumor regression grade (TRG) and pTNM staging system were used to classify pathological response and define pathological complete response (pCR). Patients were divided in: pCR (pT0N0) and Not-pCR (pT>0N>0), according to pTNM and in good responders (TRG1-2) and partial/not responders (TRG3-5), according to Mandard TRG. The Kaplan-Meier method was used to estimate OS, CSS, DFS and LC. RESULTS: A low severe toxicity rate was observed. Acute Grade 3 lower bowel toxicity and Grade 3 cutaneous toxicity were reported in 2 (1.1%) patients, respectively. Late Grade >3 lower bowel toxicity was reported in 6 patients (3%) and late Grade >3 cutaneous toxicity was registered in one patient. No other severe acute and late toxicities were reported. The 5- and 10-year OS, CSS, DFS and LC rates were 85% and 75%, 94% and 92%, 83% and 81%, 88% and 88%, respectively. We observed a pCR rate of 36% and a good responders rate of 62%, in our study population. Both groups showed better rates for each analyzed clinical outcome. CONCLUSION: Neoadjuvant radiochemotherapy with dose intensification in LARC patients resulted in favorable long-term oncological outcomes, pCR rate showed an optimal impact on OS and DFS with an acceptable toxicity.

[An update on total neoadjuvant treatment of adenocarcinoma of the rectum]. / Actualisation des données sur le traitement néoadjuvant total de l'adénocarcinome du rectum.

A major advance has been made in the management of rectal cancer, with the emergence in 2021 of total neoadjuvant treatment. The main publications from the RAPIDO and PRODIGE-23 trials reported a significant improvement in progression-free survival and the pathological complete response rate. The aim of this review is to synthesize recent data on neoadjuvant treatment of rectal cancer, to explain the long-term results of the RAPIDO and PRODIGE-23 trials, and to put them into perspective, considering current advances in de-escalation strategies. The update of the 5-year survival data from the RAPIDO trial highlights an increased risk of loco-regional relapse, with 11.7% of relapses in the experimental group and 8.1% in the control group, while the update of the PRODIGE-23 trial confirms the benefits of this treatment regimen, with a significant improvement in overall survival. In addition, the results of the OPRA and PROPSPECT trials confirm the benefit of total neoadjuvant treatment with induction chemotherapy, as well as the possibility of surgical de-escalation in the OPRA trial and radiotherapy in the PROSPECT trial. The challenge for the future is to identify patients who require total neoadjuvant treatment with the aim of curative surgery to obtain a cure without local or distant relapse, and those for whom therapeutic de-escalation can be envisaged.

Income disparities in loss in life expectancy after colon and rectal cancers: a Swedish register-based study.

BACKGROUND: Differences in the prognosis after colorectal cancer (CRC) by socioeconomic position (SEP) have been reported previously; however, most studies focused on survival differences at a particular time since diagnosis. We quantified the lifetime impact of CRC and its variation by SEP, using individualised income to conceptualise SEP. METHODS: Data included all adults with a first-time diagnosis of colon or rectal cancers in Sweden between 2008 and 2021. The analysis was done separately for colon and rectal cancers using flexible parametric models. For each cancer and income group, we estimated the life expectancy in the absence of cancer, the life expectancy in the presence of cancer and the loss in life expectancy (LLE). RESULTS: We found large income disparities in life expectancy after a cancer diagnosis, with larger differences among the youngest patients. Higher income resulted in more years lost following a cancer diagnosis. For example, 40-year-old females with colon cancer lost 17.64 years if in the highest-income group and 13.68 years if in the lowest-income group. Rectal cancer resulted in higher LLE compared with colon cancer. Males lost a larger proportion of their lives. All patients, including the oldest, lost more than 30% of their remaining life expectancy. Based on the number of colon and rectal cancer diagnoses in 2021, colon cancer results in almost double the number of years lost compared with rectal cancer (24 669 and 12 105 years, respectively). CONCLUSION: While our results should be interpreted in line with what individualised income represents, they highlight the need to address inequalities.

Outcomes of rectal cancer patients who refuse surgery after incomplete clinical response to neoadjuvant therapy.

BACKGROUND AND OBJECTIVES: Total mesorectal excision (TME) remains the standard of care for patients with rectal cancer who have an incomplete response to total neoadjuvant therapy (TNT). A minority of patients will refuse curative intent resection. The aim of this study is to examine the outcomes for these patients. METHODS: A retrospective cohort study of stage 1-3 rectal adenocarcinoma patients who underwent neoadjuvant chemoradiation therapy or TNT at a single institution. Patients either underwent TME, watch-and-wait protocol, or if they refused TME, were counseled and watched (RCW). Clinical outcomes and resource utilization were examined in each group. RESULTS: One hundred seventy-one patients (Male 59%) were included with a median surveillance of 43 months. Twenty-nine patients (17%) refused TME and had shortened overall survival (OS). Twelve patients who refused TME converted to a complete clinical response (cCR) on subsequent staging with a prolonged OS. 92% of these patients had a near cCR at initial staging endoscopy. Increased physician visits and testing was utilized in RCW and WW groups. CONCLUSION: A significant portion of patients convert to cCR and have prolonged OS. Lengthening the time to declare cCR may be considered in select patients, such as those with a near cCR at initial endoscopic staging.

Outcomes Following Pelvic Exenteration for Locally Recurrent Rectal Cancer With and Without En Bloc Sacrectomy.

BACKGROUND: Extended radical resection is often the only chance of cure for locally recurrent rectal cancer. Recurrence in the posterior compartment often necessitates en bloc sacrectomy as part of pelvic exenteration to obtain clear resection margins and provide survival benefit. OBJECTIVE: To compare oncological outcomes, morbidity, and quality-of-life outcomes following pelvic exenteration with and without en bloc sacrectomy for recurrent rectal cancer. DESIGN: Comparative cohort study with retrospective analysis of prospectively collected data. SETTING: This study was conducted at a high-volume pelvic exenteration center. PATIENTS: Patients who underwent pelvic exenteration for locally recurrent rectal cancer between 1994 and 2022. MAIN OUTCOME MEASURES: Overall survival, postoperative morbidity, R0 resection margin, and quality-of-life outcomes. RESULTS: Of 965 patients, 305 (31.6%) underwent pelvic exenteration for locally recurrent rectal cancer. Among these patients, 64.3% were men and the median age was 62 years (range, 29-86). One hundred eighty-five patients (60.7%) underwent en bloc sacrectomy, 65 (35.1%) underwent high transection, and 119 (64.3%) had sacrectomy below S2. R0 resection was achieved in 80% of patients with sacrectomy and 72.5% of patients without sacrectomy. Sacrectomy patients experienced more postoperative complications without increased mortality. The median overall survival was 52 months; median survival was 47 months with sacrectomy and 73 months without ( p = 0.059). Quality-of-life scores were not significantly different across physical component ( p = 0.346), mental component ( p = 0.787), or Functional Assessment of Cancer Therapy-Colorectal ( p = 0.679) scores at 24-month follow-up. LIMITATIONS: The generalizability of these findings may be limited outside of subspecialist exenteration units. Selection bias exists in a retrospective analysis. CONCLUSIONS: Patients undergoing pelvic exenteration with and without en bloc sacrectomy for locally recurrent rectal cancer experience similar rates of R0 resection, survival, and quality-of-life outcomes. As R0 remains the most important predictor of survival, the requirement of sacral resection should prompt referral to a subspecialist center that performs sacrectomy routinely. See Video Abstract . RESULTADOS DESPUS DE LA EXENTERACIN PLVICA PARA EL CNCER DE RECTO CON RECURRENCIA LOCAL, CON Y SIN SACRECTOMA EN BLOQUE: ANTECEDENTES:La resección radical ampliada es generalmente la única posibilidad de curación para el cáncer de recto con recurrencia local. La recurrencia en el compartimento posterior generalmente requiere sacrectomía en bloque como parte de la exenteración pélvica para obtener márgenes de resección claros y proporcionar un beneficio de supervivencia.OBJETIVO:Comparar los resultados oncológicos, de morbilidad y de calidad de vida después de la exenteración pélvica con y sin sacrectomía en bloque para el cáncer de recto recurrente.DISEÑO:Estudio de cohorte comparativo con análisis retrospectivo de datos recopilados prospectivamente.AMBIENTE AJUSTE:Estudio realizado en un centro de exenteración pélvica de alto volumen.PACIENTES:Aquellos sometidos a exenteración pélvica por cáncer de recto con recurrencia local entre 1994 y 2022.PRINCIPALES MEDIDAS DE RESULTADO:Supervivencia general, morbilidad posoperatoria, margen de resección R0 y resultados de calidad de vida.RESULTADOS:305 (31,6%) de 965 pacientes se sometieron a exenteración pélvica por cáncer de recto con recurrencia local. El 64,3% de los pacientes eran hombres con una mediana de edad de 62 años (rango 29-86). 185 pacientes (60,7%) fueron sometidos a sacrectomía en bloque, 65 (35,1%) fueron sometidos a transección alta, 119 (64,3%) tuvieron sacrectomía por debajo de S2. La resección R0 se logró en el 80% de los pacientes con sacrectomía y en el 72,5% sin ella. Los pacientes de sacrectomía experimentaron más complicaciones postoperatorias sin aumento de la mortalidad. La mediana de supervivencia global fue de 52 meses, 47 meses con sacrectomía y 73 meses sin sacrectomía ( p = 0,059). Las puntuaciones de calidad de vida no fueron significativamente diferentes entre las puntuaciones del componente físico ( p = 0,346), componente mental ( p = 0,787) o la evaluación funcional de la terapia contra el cáncer - colorrectal ( p = 0,679) a los 24 meses de seguimiento.LIMITACIONES:La generalización de estos hallazgos puede estar limitada fuera de las unidades de exenteración de subespecialistas. Existe un sesgo de selección en un análisis retrospectivo.CONCLUSIONES:Los pacientes sometidos a exenteración pélvica con y sin sacrectomía en bloque por cáncer de recto con recurrencia local experimentan tasas similares de resección R0, supervivencia y resultados de calidad de vida. Como R0 sigue siendo el predictor más importante de supervivencia, la necesidad de resección sacra debe provocar la derivación a un centro subespecialista que realice sacrectomía de forma rutinaria. (Traducción-Dr. Fidel Ruiz Healy ).

Clinical and genetic factors associated with tumor response to neoadjuvant (chemo)radiotherapy, survival and recurrence risk in rectal cancer.

Rectal cancer poses challenges in preoperative treatment response, with up to 30% achieving a complete response (CR). Personalized treatment relies on accurate identification of responders at diagnosis. This study aimed to unravel CR determinants, overall survival (OS), and time to recurrence (TTR) using clinical and targeted sequencing data. Analyzing 402 patients undergoing preoperative treatment, tumor stage, size, and treatment emerged as robust response predictors. CR rates were higher in smaller, early-stage, and intensively treated tumors. Targeted sequencing analyzed 216 cases, while 120 patients provided hotspot mutation data. KRAS mutation dramatically reduced CR odds by over 50% (odds ratio [OR] = 0.3 in the targeted sequencing and OR = 0.4 hotspot cohorts, respectively). In contrast, SMAD4 and SYNE1 mutations were associated with higher CR rates (OR = 6.0 and 6.8, respectively). Favorable OS was linked to younger age, CR, and low baseline carcinoembryonic antigen levels. Notably, CR and an APC mutation increased TTR, while a BRAF mutation negatively affected TTR. Beyond tumor burden, SMAD4 and SYNE1 mutations significantly influenced CR. KRAS mutations independently correlated with radiotherapy resistance, and BRAF mutations heightened recurrence risk. Intriguingly, non-responding tumors with initially small sizes carried a higher risk of recurrence. The findings, even if limited in addition to the imperfect clinical factors, offer insights into rectal cancer treatment response, guiding personalized therapeutic strategies. By uncovering factors impacting CR, OS, and TTR, this study underscores the importance of tailored approaches for rectal cancer patients. These findings, based on extensive analysis and mutation data, pave the way for personalized interventions, optimizing outcomes in the challenges of rectal cancer preoperative treatment.

MRI-defined T3, clear mesorectal fascia mid-low rectal cancer: is neoadjuvant treatment necessary?

AIM: Neoadjuvant treatments (nCRT) are becoming the standard treatment for patients with stage II or III mid-low rectal cancer. Recently, some studies have shown that surgery alone may be sufficient for patients with T3 rectal cancer. This raises the question of whether nCRT is necessary for all patients with T3 rectal cancer. Therefore, this study compared the clinical outcomes of patients with MRI-defined T3, clear MRF mid-low rectal cancer treated with surgery alone (TME group) or nCRT followed by surgery (nCRT + TME group). METHODS: A total of 1509 patients were enrolled in this study. After a 1:1 propensity score matching analysis, 480 patients were included in each group. The primary endpoint was 3-year disease-free survival (DFS). The secondary endpoints included the perioperative outcomes, histopathologic outcomes, and other follow-up outcomes. RESULTS: nCRT had advantages in rates of sphincter-preserving surgery and tumor downstaging, but it was accompanied by a higher rate of enterostomies. At 3 years after surgery, local recurrence occurred in 3.3% of patients in the TME group and in 3.5% of patients in the nCRT + TME group (P = 0.914), the DFS rates were 78.3% in the TME group and 75.3% in the nCRT + TME group (P = 0.188), and the overall survival rates were 90.3% in the TME group and 89.9% in the nCRT + TME group (P = 0.776). CONCLUSIONS: Surgery alone versus nCRT followed by surgery may provide similar long-term oncological outcomes for patients with MRI-defined T3, clear MRF, and mid-low rectal cancer. nCRT may cause overtreatment in some patients.

Reporting of Circumferential Resection Margin in Rectal Cancer Surgery.

Importance: Circumferential resection margin (CRM) in rectal cancer surgery is a major prognostic indicator associated with local recurrence and overall survival. Facility rates of CRM positivity have recently been established as a new quality measure by the Commission on Cancer (CoC); however, the completeness of CRM status reporting is not well characterized. Objective: To describe the changes in CRM reporting and factors associated with low rates of reporting. Design, Setting, and Participants: A retrospective cohort study was conducted using data from the National Cancer Database between January 2010 and December 2019. Data were analyzed between October 1, 2021, and February 1, 2022. Data from the National Cancer Database included patients diagnosed with nonmetastatic rectal adenocarcinoma receiving surgical treatment at CoC-accredited facilities throughout the US. Exposures: Patient, tumor, and facility-level factors. Facilities were divided by surgical volume, safety-net status, and CoC facility type. Main Outcomes and Measures: Circumferential resection margin missingness rates. Results: A total of 110 571 patients (59.3% men) with rectal adenocarcinoma who underwent curative-intent surgery at 1307 CoC-accredited hospitals were included for analysis. Reporting of CRM improved over the study period, with a mean (SE) missing 12.0% (0.32%) decreased from 16.3% (0.36%). Academic facilities had a higher missingness than other facility types (14.3% vs 10.5%-12.7%; P < .001). Mean (SE) rates of missingness were similar between hospitals of varying volume (lowest quartile: 12.2% [0.93%] vs highest quartile: 12.4% [0.53%]; P = .96). Cases in which fewer than 12 lymph nodes were removed had higher rates of missingness (18.1% vs 11.4%; P < .001). Increased odds of CRM missingness were noted with T category (odds ratio [OR], 1.50; 95% CI, 1.35-1.65) and N category (OR, 2.00; 95% CI, 1.82-2.20). Black race was associated with missingness (OR, 1.13; 95% CI, 1.06-1.14). Conclusion and Relevance: Although CRM positivity reporting has improved over the last decade, the findings of this study suggest there is substantial room for improvement as it becomes a quality standard. Missingness appears to be associated with poor performance on other quality metrics and facility type. This measure appears to be ideal for targeted institution-level feedback to improve quality of care nationally.

Specialty-Certified Colorectal Surgeons Demonstrate Favorable Short-term Surgical Outcomes for Laparoscopic Low Anterior Resection: Assessment of a Japanese Nationwide Database.

BACKGROUND: There are few studies on the impact of a colorectal-specific technically certified surgeon on good surgical outcomes for laparoscopic low anterior resection in the real world. OBJECTIVE: To evaluate the short-term outcomes of laparoscopic low anterior resection with the participation of a certified colorectal surgeon. DESIGN: This was a retrospective cohort study using a Japanese nationwide database. SETTING: This study was conducted as a project for the Japan Society of Endoscopic Surgery and the Japanese Society of Gastroenterological Surgery. PATIENTS: This study included 41,741 patients listed in the National Clinical Database who underwent laparoscopic low anterior resection performed by certified, noncertified, and colorectal-specific certified surgeons, according to the Endoscopic Surgical Skill Qualification System, from 2016 to 2018. MAIN OUTCOME MEASURES: Operative mortality rate and anastomotic leak rate were the primary outcome measures. RESULTS: Overall 30-day mortality and operative mortality were 0.2% and 0.3%, respectively, without significant differences between all kinds of certified and noncertified surgeon groups. Overall anastomotic leak rate was 9.3%, with a significant difference between the 2 groups. Colorectal- and stomach-certified groups had lower 30-day mortality and operative mortality than the biliary-certified and noncertified groups. The anastomotic leak rate was the lowest in the colorectal-certified group. Based on a logistic regression analysis using the risk-adjusted model, operative mortality was significantly higher in the biliary-certified group than in the colorectal-certified group. Moreover, anastomotic leak rate was significantly lower in the colorectal-certified group than in the stomach-certified and noncertified groups. LIMITATIONS: This study was a retrospective study, and there was a possibility of different definitions of anastomotic leak due to the use of a nationwide database. CONCLUSIONS: The participation of a colorectal-specific certified surgeon may decrease the risk of operative mortality and anastomotic leak for laparoscopic low anterior resection. CIRUJANO COLORRECTAL ALTAMENTE CALIFICADO PROVOCA RESULTADOS QUIRRGICOS FAVORABLES A CORTO PLAZO PARA LA RESECCIN ANTERIOR BAJA LAPAROSCPICA EVALUACIN DE LA BASE DE DATOS NACIONAL JAPONESA: ANTECEDENTES:Hay pocos estudios sobre el impacto de un cirujano certificado técnicamente especializado en cáncer colorrectal con un buen resultado quirúrgico para la resección anterior baja laparoscópica en el mundo real.OBJETIVO:Evaluar los resultados a corto plazo de la resección anterior baja laparoscópica con la participación de un cirujano colorrectal certificado.DISEÑO:Este fue un estudio de cohorte retrospectivo que utilizó una base de datos nacional japonesa.AJUSTE:Este estudio se realizó como un proyecto para la Sociedad Japonesa de Cirugía Endoscópica y la Sociedad Japonesa de Cirugía Gastroenterológica.PACIENTES:este estudio incluyó a 41 741 pacientes incluidos en la base de datos clínica nacional que se sometieron a una resección anterior baja laparoscópica realizada por cirujanos certificados, no certificados y certificados específicamente colorrectales, según el Sistema de calificación de habilidades quirúrgicas endoscópicas de 2016 a 2018.PRINCIPALES MEDIDAS DE RESULTADO:La tasa de mortalidad operatoria y la tasa de fuga anastomótica fueron los resultados primarios.RESULTADOS:La mortalidad general a los 30 días y la mortalidad operatoria fueron del 0,2 % y el 0,3 %, respectivamente, sin diferencias significativas entre los grupos de todos los tipos de cirujanos certificados y no certificados. La tasa global de fuga anastomótica fue del 9,3 %, con una diferencia significativa entre los dos grupos. Los grupos con certificación colorrectal y estomacal tuvieron una mortalidad a los 30 días y una mortalidad operatoria más bajas que los grupos con certificación biliar y sin certificación. La tasa de fuga anastomótica fue la más baja en el grupo certificado colorrectal. Con base en un análisis de regresión logística utilizando el modelo ajustado por riesgo, la mortalidad operatoria fue significativamente más alta en el grupo con certificación biliar que en el grupo con certificación colorrectal. Además, la tasa de fuga anastomótica fue significativamente más baja en el grupo con certificación colorrectal que en los grupos con certificación estomacal y sin certificación.LIMITACIONES:Este estudio fue retrospectivo y existía la posibilidad de diferentes definiciones de fuga anastomótica debido al uso de una base de datos nacional.CONCLUSIONES:La participación de un cirujano certificado en video específico colorrectal puede disminuir el riesgo de mortalidad operatoria y fuga anastomótica para la resección anterior baja laparoscópica. (Traducción-Dr. Mauricio Santamaria ).

Heterogeneidad del tumor primario en la18F-FDG PET/TC pretratamiento para predecir el pronóstico en pacientes con cáncer de recto sometidos a cirugía tras terapia neoadyuvante / Primary tumor heterogeneity on pretreatment18F-FDG PET/CT to predict outcome in patients with rectal cancer who underwent surgery after neoadjuvant therapy

Objetivo Estudio retrospectivo cuyo objetivo fue investigar el valor de las características de textura de los tumores primarios en la PET/TC con 18F-FDG pretratamiento para la predicción de la respuesta al tratamiento, la progresión y la supervivencia global en pacientes con cáncer de recto que se sometieron a cirugía después de la terapia neoadyuvante (TNA). Métodos Se incluyeron en este estudio pacientes con cáncer de recto que se sometieron a estudio PET/TC con 18F-FDG antes del tratamiento y se sometieron a cirugía después de TNA. Se registraron las características clínico-patológicas, la fecha del último seguimiento, la evolución y fallecimiento. Los parámetros de las texturas y los convencionales de PET (Standard Uptake Value-SUVmax, volumen tumoral metabólico-MTV, glucólisis total de la lesión-TLG) se obtuvieron a partir de imágenes PET/TC utilizando el programa LifeX. Los parámetros se agruparon utilizando el índice de Youden en el análisis ROC. Los factores que predicen la respuesta patológica al tratamiento, la progresión y la supervivencia global se determinaron mediante regresión logística y análisis de regresión de Cox. Resultados Cuarenta y cuatro pacientes (26-59% hombres, 18-41% mujeres; 60,1 ± 11,4 años) con cáncer de recto fueron incluidos en este estudio. El número de pacientes respondedores y no respondedores a TNA fueron de 15 (34,9%) y 28 (65,1%), respectivamente. La mediana de la duración del seguimiento fue de 29,9 meses. 9 (20,5%) mostraron progresión de la enfermedad y 8 (18,2%) fallecieron durante el período de seguimiento. Los parámetros de entropía GLCM de diferencia y correlación GLCM se encontraron como predictores independientes para la respuesta a TNA. Los parámetros de positividad del margen quirúrgico, rango intercuartílico de intensidad CONV y textura AUC-CSHDISC fueron predictores independientes de progresión (AU)

Purpose This retrospective study aimed to investigate the value of texture features of primary tumors in pretreatment18F-FDG PET/CT in the prediction of response to treatment, progression, and overall survival in patients with rectal cancer who underwent surgery after neoadjuvant therapy (NAT). Method Patients with rectal cancer who had pretreatment18F-FDG PET/CT, and underwent surgery after NAT were included in this study. Clinicopathologic features, date of last follow-up, progression, and death were recorded. Textural and conventional PET parameters (maximum standardized uptake value-SUVmax, metabolic tumor volume-MTV, total lesion glycolysis-TLG) were obtained from PET/CT images using LifeX program. Parameters were grouped using Youden index in ROC analysis. Factors predicting the pathological response to treatment, progression, and overall survival were determined using logistic regression and Cox regression analyses. Results Forty-four patients (26(59%) male, 18 (41%) female; 60.1 ± 11.4 years) with rectal cancer were included in this study. The numbers of patients with responders and non-responders to NAT were15(34.9%) and 28(65.1%), respectively. One patient’ pathology report did not contain the response status to NAT. The median of follow-up duration was 29.9 months. 9(20.5%) showed disease progression, and 8(18.2%) died during the follow-up period. Difference entropy GLCM and correlation GLCM parameters were found as independent predictors for response to NAT. The positivity of surgical margin, intensity interquartile range CONV and AUC-CSHDISC texture parameters were independent predictors of progression, while normalized inverse difference GLCM and LZLGEGLZLM parameters were independent predictorsof mortality. Conclusion The texture parameters obtained from pretreatment18F-FDG PET/CT have presented a more robust predictive value than conventional parameters in patients with rectal cancer who underwent surgery after NAT (AU)

Preoperative Treatment of Locally Advanced Rectal Cancer.

BACKGROUND: Pelvic radiation plus sensitizing chemotherapy with a fluoropyrimidine (chemoradiotherapy) before surgery is standard care for locally advanced rectal cancer in North America. Whether neoadjuvant chemotherapy with fluorouracil, leucovorin, and oxaliplatin (FOLFOX) can be used in lieu of chemoradiotherapy is uncertain. METHODS: We conducted a multicenter, unblinded, noninferiority, randomized trial of neoadjuvant FOLFOX (with chemoradiotherapy given only if the primary tumor decreased in size by <20% or if FOLFOX was discontinued because of side effects) as compared with chemoradiotherapy. Adults with rectal cancer that had been clinically staged as T2 node-positive, T3 node-negative, or T3 node-positive who were candidates for sphincter-sparing surgery were eligible to participate. The primary end point was disease-free survival. Noninferiority would be claimed if the upper limit of the two-sided 90.2% confidence interval of the hazard ratio for disease recurrence or death did not exceed 1.29. Secondary end points included overall survival, local recurrence (in a time-to-event analysis), complete pathological resection, complete response, and toxic effects. RESULTS: From June 2012 through December 2018, a total of 1194 patients underwent randomization and 1128 started treatment; among those who started treatment, 585 were in the FOLFOX group and 543 in the chemoradiotherapy group. At a median follow-up of 58 months, FOLFOX was noninferior to chemoradiotherapy for disease-free survival (hazard ratio for disease recurrence or death, 0.92; 90.2% confidence interval [CI], 0.74 to 1.14; P = 0.005 for noninferiority). Five-year disease-free survival was 80.8% (95% CI, 77.9 to 83.7) in the FOLFOX group and 78.6% (95% CI, 75.4 to 81.8) in the chemoradiotherapy group. The groups were similar with respect to overall survival (hazard ratio for death, 1.04; 95% CI, 0.74 to 1.44) and local recurrence (hazard ratio, 1.18; 95% CI, 0.44 to 3.16). In the FOLFOX group, 53 patients (9.1%) received preoperative chemoradiotherapy and 8 (1.4%) received postoperative chemoradiotherapy. CONCLUSIONS: In patients with locally advanced rectal cancer who were eligible for sphincter-sparing surgery, preoperative FOLFOX was noninferior to preoperative chemoradiotherapy with respect to disease-free survival. (Funded by the National Cancer Institute; PROSPECT ClinicalTrials.gov number, NCT01515787.).

Evaluating whether KRAS/BRAF mutation status, anaemia and obstruction are associated with recurrence and mortality in non-metastatic colorectal cancer.

BACKGROUND: KRAS and BRAF testing is currently recommended in metastatic colorectal cancer. There is evidence that KRAS and BRAF mutation status may act as a prognostic biomarker in patients with non-metastatic colorectal cancer. Data is limited on whether KRAS and BRAF mutation status impacts recurrence and mortality in patients with non-metastatic colorectal cancer. METHODS: A retrospective cohort study was conducted in a tertiary hospital examining outcomes in patients who had KRAS and BRAF testing for colorectal cancer in 2017. Primary outcomes were all-cause mortality and recurrence. Multivariable analysis for both outcomes, used cause specific Cox proportional hazards models with KRAS/BRAF status as exposure. For time to recurrence, a sensitivity analysis was performed with a weighted Fine-Grey model with death as a competing risk. RESULTS: KRAS mutation status was not associated with all-cause mortality (average Hazard Ratio (aHR) = 0.78, 95% CI 0.28-2.21) or recurrence (aHR = 0.96, 95% CI 0.32-2.86). BRAF mutation status was not associated with time to all-cause mortality (aHR = 3.06, 95% CI 0.79-11.8) or recurrence (aHR = 0.94, 95% CI 0.13-6.57). Increased risk of recurrence was significantly associated with large bowel obstruction (aHR = 2.73, 95% CI 1.16-6.45) and anaemia (aHR = 3.39, 95% CI 1.06-10.8) at time of surgery. CONCLUSION: This study did not demonstrate an association between KRAS and BRAF mutations and all-cause mortality or recurrence. A significantly increased risk of cancer recurrence was found in patients with large bowel obstruction and in patients with anaemia at time of surgery. Anaemia should be promptly investigated and corrected prior to colorectal cancer surgery.

Evaluación de la supervivencia de los pacientes con cáncer de recto metastásico mediante parámetros radiómicos y volumétricos de la PET/TC con [18F]FDG de estadificación / Evaluation of the survival of patients with metastatic rectal cancer by staging [18F]FDG PET/CT radiomic and volumetric parameters

Objetivo El objetivo de este estudio es predecir el pronóstico de pacientes con cáncer de recto metastásico (CRM) mediante la obtención de un modelo con algoritmos de aprendizaje automático (AA) a través de datos volumétricos y radiómicos obtenidos de la PET/TC basal. Métodos Pacientes con CRM que se sometieron a imágenes PET/TC con [18F]FDG para estadificación en nuestro hospital entre enero 2015 y enero de 2021 se evaluaron mediante el software LIFEx. El volumen de interés (VOI) del tumor primario fue generado. Además, se evaluaron los valores del volumen metabólico tumoral total (tMTV) y la glucólisis de lesión total (TLG) de los focos tumorales en todo el cuerpo. Se evaluaron los datos clínicos y radiómicos con algoritmos de AA para crear un modelo que predijera la supervivencia. Se investigaron asociaciones significativas entre estas características y la supervivencia a 1 y 2 años. Resultados El algoritmo de bosque aleatorizado fue el algoritmo más exitoso para predecir la supervivencia a 2 años (AUC: 0,843; PRC: 0,822 y CCM: 0,583). Los valores de tMTV y tTLG tuvieron éxito en la predicción de la supervivencia a un año (p 0,002 y 0,007, respectivamente). Conclusiones Además del importante papel de la PET/TC con [18F]FDG en la estadificación de pacientes con CRM, este estudio muestra que es posible predecir la supervivencia con métodos de AA, con parámetros obtenidos mediante el análisis de textura a partir del tumor primario y parámetros volumétricos de todo el cuerpo (AU)

Objective The aim of this study was to predict the prognosis in patients with metastatic rectal cancer (mRC) by obtaining a model with machine learning (ML) algorithms through volumetric and radiomic data obtained from baseline 18-Fluorine Fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) images. Methods Sixty-two patients with mRC who underwent [18F]FDG PET/CT imaging for staging between January 2015 and January 2021 were evaluated using LIFEx software. The volume of interest (VOI) of the primary tumor was generated and volumetric and textural features were obtained from this VOI. In addition, the total metabolic tumor volume (tMTV) and total lesion glycolysis (TLG) values of tumor foci in the whole body were evaluated. Clinical and radiomic data were evaluated with ML algorithms to create a model that predicts survival. Significant associations between these features and 1- and 2-year survival were investigated. Results The random forest algorithm was the most successful in predicting 2-year survival (AUC: 0.843, precision-recall curve: 0.822 and Matthew's correlation coefficient: 0.583). The model obtained with this algorithm was able to predict 49 patients with 79.03% accuracy. While tMTV and TLG values were successful in predicting 1-year survival (p: 0.002 and 0.007, respectively), texture characteristics of the primary tumor did not show a significant relationship with 1-year survival. Conclusions In addition to the important role of [18F]FDG PET/CT in staging patients with mRC, this study shows that it is possible to predict survival with ML methods, with parameters obtained using texture analysis of the primary tumor and whole body volumetric parameters (AU)

Impact of rectal washout on recurrence and survival after anterior resection for rectal cancer.

BACKGROUND: Rectal washout (RW) is routinely performed during anterior resection (AR) for rectal cancer to reduce local recurrence (LR), although is sometimes not performed during minimally invasive surgery (MIS) procedures due to technical challenges and time consumption. The aim was to investigate the impact of RW on the oncological outcome after AR for rectal cancer in a registry cohort. METHODS: Data on patients registered in the Swedish Colorectal Cancer Registry who had undergone elective radical (R0) AR for TNM stage I-III rectal cancer between 2007 and 2017 with a 3-year follow-up were analysed. Multivariable analyses were performed and the primary endpoint was LR at 3 and 5 years after AR. The occurrence of distant metastasis (DM) and overall recurrence (OAR), overall survival, and relative survival were also analysed as a secondary aim. A subgroup analysis was performed for the same outcomes in patients treated with MIS. RESULTS: Out of 6186 patients (1923 with TNM stage I, 1907 with TNM stage II, and 2356 with TNM stage III), RW was performed in 5706 (92.2 per cent). The median age of the cohort was 67 years. RW did not impact the 3-year risk of LR. LR within 5 years occurred in 104 of 4583 patients (2.3 per cent) in the RW group compared with 16 of 408 patients (3.9 per cent) in the no RW group (P = 0.037). In multivariable analysis of the LR risk, the HR was 0.53 (95 per cent c.i. 0.31 to 0.90), favouring RW. There were no differences in rates of DM and OAR, overall survival, and relative survival. A subgroup analysis of the 1410 patients undergoing MIS did not demonstrate any differences between the groups, given, however, the low rate of LR. CONCLUSIONS: RW in AR for rectal cancer does not impact the 3-year oncological outcome; however, after the 5-year follow-up a reduction in LR risk was observed after RW.

Pattern of rectal cancer recurrence following potentially curative surgical treatment

Survival in rectal cancer has been related mainly to clinical and pathological staging. Recurrence is the most challenging issue when surgical treatment of rectal cancer is concerned. This study aims to establish a recurrence pattern for rectal adenocarcinoma submitted to surgical treatment between June 2003 and July 2021. After applying the exclusion criteria to 305 patients, 166 patients were analyzed. Global recurrence was found in 18.7% of them, while 7.8% have had local recurrence. Recurrences were diagnosed from 5 to 92 months after the surgical procedure, with a median of 32.5 months. Follow-up varied from 6 to 115 months. Recurrence, in literature, is usually between 3 and 35% in 5 years and shows a 5-year survival rate of only 5%. In around 50% of cases, recurrence is local, confined to the pelvis. This study was consonant with the literature in most aspects evaluated, although a high rate of local recurrence remains a challenge in seeking better surgical outcomes. (AU)

A longitudinal cohort study of watch and wait in complete clinical responders after chemo-radiotherapy for localised rectal cancer: study protocol.

BACKGROUND: Rectal Cancer is a common malignancy. The current treatment approach for patients with locally advanced rectal cancer involves neoadjuvant chemoradiotherapy followed by surgical resection of the rectum. The resection can lead to complications and long-term consequences. A clinical complete response is observed in some patients after chemoradiotherapy. A number of recent studies have shown that patients can be observed safely after completing chemoradiotherapy (without surgery), provided clinical complete response has been achieved. In this approach, resection is reserved for cases of regrowth. This is called the watch and wait approach. This approach potentially avoids unnecessary surgical resection of the rectum and the resulting complications. In this study, we will prospectively investigate this approach. METHODS: Adult patients with a diagnosis of rectal cancer planned to receive neoadjuvant long course chemoradiotherapy (± subsequent combination chemotherapy) will be consented into the study prior to commencing treatment. After completing the chemoradiotherapy (± subsequent combination chemotherapy), based on the clinical response, subjects will be allocated to one of the following arms: subjects who achieved a clinical complete response will be allocated to the watch and wait arm and others to the standard management arm (which includes resection). The aim of the study is to determine the rate of local failure and other safety and efficacy outcomes in the watch and wait arm. Patient reported outcome measures and the use of biomarkers as part of the clinical monitoring will be studied in both arms of the study. DISCUSSION: This study will prospectively investigate the safety of the watch and wait approach. We will investigate predictive biomarkers (molecular biomarkers and imaging biomarkers) and patient reported outcome measures in the study population and the cost effectiveness of the watch and wait approach. This study will also help evaluate a defined monitoring schedule for patients managed with the watch and wait approach. This protocol covers the first two years of follow up, we are planning a subsequent study which covers year 3-5 follow up for the study population. TRIAL REGISTRATION: Name of the registry: Australia and New Zealand Clinical Trials Registry (ANZCTR). TRIAL REGISTRATION NUMBER: Trial ID: ACTRN12619000207112 Registered 13 February 2019, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=376810.

Prognostic significance of lateral pelvic lymph node dissection for middle-low rectal cancer patients with lateral pelvic lymph node metastasis: a propensity score matching study.

BACKGROUND: There is still controversy regarding the clinical value and significance of lateral pelvic lymph node (LPN) dissection (LPND). The present study aimed to investigate whether the addition of LPND to total mesorectal excision (TME) confers survival benefits in rectal cancer patients with clinical lateral pelvic node metastasis (LPNM). METHODS: From January 2015 to January 2021, a total of 141 rectal cancer patients with clinical evidence of LPNM who underwent TME + LPND were retrospectively analysed and divided into the LPNM group (n = 29) and the non-LPNM group (n = 112). The LPNM group was further subdivided into a high-risk LPNM group (n = 14) and a low-risk LPNM group (n = 15). Propensity score matching (PSM) was performed to minimize selection bias. The primary outcomes of this study were 3-year overall survival (OS) and disease-free survival (DFS). RESULTS: Of the 141 patients undergoing LPND, the local recurrence rate of patients with LPNM was significantly higher than that of patients without LPNM both before (27.6% vs. 4.5%, P = 0.001) and after (27.6% vs. 3.4%, P = 0.025) PSM. Multivariate analysis revealed that LPNM was an independent risk factor for not only OS (HR: 3.06; 95% CI, 1.15-8.17; P = 0.025) but also DFS (HR: 2.39; 95% CI, 1.18-4.87; P = 0.016) in patients with LPNM after TME + LPND. When the LPNM group was further subdivided, multivariate logistic regression analysis showed that OS and DFS were significantly better in the low-risk group (obturator/internal iliac artery region and < 2 positive LPNs). CONCLUSION: Even after LPND, LPNM patients have a poor prognosis. Moreover, LPNM is an independent poor prognostic factor affecting OS and DFS after TME + LPND. However, LPND appears to confer survival benefits to specific patients with single LPN involvement in the obturator region or internal iliac vessel region. Furthermore, LPND may have no indication in stage IV patients and should be selected carefully.

The Prognostic Value of FoxP3+ Tumour-Infiltrating Lymphocytes in Rectal Cancer Depends on Immune Phenotypes Defined by CD8+ Cytotoxic T Cell Density.

Tumour-infiltrating FoxP3+ regulatory T cells have been identified as both positive and negative prognostic factors in colorectal cancer (CRC) and rectal cancer (RC). In this study we investigated whether immune phenotypes, defined by CD8+ cytotoxic T cell density, may influence the prognostic association of FoxP3+ T cell densities in RC. Tissue microarrays from 154 rectal cancer resections were immunohistochemically double stained for CD8 and FoxP3. CD8+ and FoxP3+ cell densities were measured in the stromal and intraepithelial compartment. Stromal FoxP3+ cell densities were not associated with 10-year overall survival (OS). In the "immune-desert" phenotype, defined by very low stromal CD8+ cell density, a high density of stromal FoxP3+ T cells displayed a tendency towards an association with decreased 10-year OS (p = 0.179). In "inflamed" tumours, defined by high intraepithelial CD8+ T cell infiltration, the opposite was the case and high stromal FoxP3+ T cell densities were a positive prognostic factor (p = 0.048). Additionally, patients with an increased FoxP3/CD8 cell density ratio demonstrated a strong trend towards decreased 10-year OS (p = 0.066). These contrasting findings suggest functional heterogeneity within the group of FoxP3+ T cells. They are consistent with experimental studies which reported suppressive and non-suppressive populations of FoxP3+ T cells in CRC. Furthermore, our study demonstrates that CD8 immunohistochemistry may act as an instrument to identify tumours infiltrated by possibly functionally differing FoxP3+ T cell subtypes.