Prognostic Relevance of Primary Tumor Sidedness in Early-stage Colorectal Cancer: An Integrated Analysis of 4 Randomized Controlled Trials (JCOG2003A).

OBJECTIVE: The aim of this study was to determine the genuine prognostic relevance of primary tumor sidedness (PTS) in patients with early-stage colorectal cancer (CRC). BACKGROUND: The prognostic relevance of PTS in early-stage CRC remains a topic of debate. Several large epidemiological studies investigated survival only and did not consider the risk of recurrence so far. METHODS: Patients with stage II/III adenocarcinoma of the colon and upper rectum from 4 randomized controlled trials were analyzed. Survival outcomes were compared according to the tumor location: right-sided (cecum to transverse colon) or left-sided (descending colon to upper rectum). RESULTS: A total of 4113 patients were divided into a right-sided group (N=1349) and a left-sided group (N=2764). Relapse-free survival after primary surgery was not associated with PTS in all patients and each stage [hazard ratio (HR) adjusted =1.024 (95% CI: 0.886-1.183) in all patients; 1.327 (0.852-2.067) in stage II; and 0.990 (0.850-1.154) in stage III]. Also, overall survival after primary surgery was not associated with PTS in all patients and each stage [HR adjusted =0.879 (95% CI: 0.726-1.064) in all patients; 1.517 (0.738-3.115) in stage II; and 0.840 (0.689-1.024) in stage III]. In total, 795 patients (right-sided, N=257; left-sided, N=538) developed recurrence after primary surgery. PTS was significantly associated with overall survival after recurrence (HR adjusted =0.773, 95% CI: 0.627-0.954). CONCLUSIONS: PTS had no impact on the risk of recurrence for stage II/III CRC. Treatment stratification based on PTS is unnecessary for early-stage CRC.

How Does Omitting Additional Surgery After Local Excision Affect the Prognostic Outcome of Patients With High-risk T1 Colorectal Cancer?

OBJECTIVE: To investigate how omitting additional surgery after local excision (LE) affects patient outcomes in high-risk T1 colorectal cancer (CRC). BACKGROUND: It is debatable whether additional surgery should be performed for all patients with high-risk T1 CRC regardless of the tolerability of invasive procedures. METHODS: Patients who had received LE for T1 CRC at the Japanese Society for Cancer of the Colon and Rectum institutions between 2009 and 2016 were analyzed. Those who had received additional surgical resection and those who did not were matched one-on-one by the propensity score-matching method. A total of 401 propensity score-matched pairs were extracted from 1975 patients at 27 Japanese Society for Cancer of the Colon and Rectum institutions and were compared. RESULTS: Regional lymph node metastasis was observed in 31 (7.7%) patients in the LE + surgery group. Comparatively, the incidence of oncologic adverse events was low in the LE-alone group, such as the 5-year cumulative risk of local recurrence (4.1%) or overall recurrence (5.5%). In addition, the difference in the 5-year cancer-specific survival between the LE + surgery and LE-alone groups was only 1.8% (99.7% and 97.9%, respectively), whereas the 5-year overall survival was significantly lower in the LE-alone group than in the LE + surgery group [88.5% vs 94.5%, respectively ( P = 0.002)]. CONCLUSIONS: Those who had decided to omit additional surgery at the dedicated center for CRC treatment presented a small number of oncologic events and a satisfactory cancer-specific survival, which may suggest an important role of risk assessment regarding nononcologic adverse events to achieve a best practice for each individual with high-risk T1 tumors.

Prognostic impact of primary tumour location after curative resection in Stage I-III colorectal cancer: a single-centre retrospective study.

OBJECTIVE: The relationship of tumour site with post-recurrence course and outcome after primary surgery in resectable colorectal cancer is unclear. This study investigated the prognostic impact of primary tumour location following radical resection without preoperative treatment in Stage I-III colorectal cancer. METHODS: We analyzed 3770 patients with Stage I-III colorectal cancer who underwent curative resection at our hospital during 2000-15. We defined the right-sided colon as the cecum, ascending colon and transverse colon, and the left-sided colon as the descending colon, sigmoid and rectosigmoid junction. Patients were divided into three groups according to tumour site: right-sided colon, left-sided colon and rectum. Endpoints were overall survival, recurrence-free survival by stage and survival after recurrence, respectively. RESULTS: The 5-year overall survival rates of patients with stage I left-sided colon cancer, right-sided colon cancer and rectal cancer were 98.2, 97.3 and 97.2%, respectively (P = 0.488). The 5-year overall survival rates of patients with Stage II left-sided colon cancer, right-sided colon cancer and rectal cancer were 96.2, 88.7 and 83.0, respectively (P = 0.070). The 5-year overall survival rates of patients with Stage III left-sided colon cancer, right-sided colon cancer and rectal cancer were 88.7, 83.0 and 80.2, respectively (P = 0.001). The 5-year recurrence-free survival rates of patients with Stage I left-sided colon cancer, right-sided colon cancer and rectal cancer were 95.1, 94.5 and 90.6% (P = 0.027). The 5-year recurrence-free survival rates of patients with Stage II left-sided colon cancer, right-sided colon cancer and rectal cancer were 85.2, 90.2 and 76.1%, respectively (P < 0.001). The 5-year recurrence-free survival rates of patients with Stage III left-sided colon cancer, right-sided colon cancer and rectal cancer were 75.3, 75.3 and 59.8%, respectively (P < 0.001). Right-sided colon cancer was significantly associated with better recurrence-free survival compared with left-sided colon cancer (HR 1.29, 95% CI 1.03-1.63; P = 0.025) and rectal cancer (HR 1.89, 95% CI 1.51-2.38; P < 0.001) after adjusting for clinical factors. Amongst patients with recurrence, right-sided colon cancer was significantly associated with poorer survival after recurrence compared with left-sided colon cancer (HR 0.68, 95% CI 0.48-0.97; P = 0.036), and showed a tendency towards poorer survival after recurrence compared with rectal cancer (HR 0.79, 95% CI 0.57-1.10; P = 0.164). CONCLUSIONS: In Stage I-III colorectal cancer without preoperative treatment, our results suggest that the three tumour sites (right-sided colon, left-sided colon or rectum) may have prognostic significance for recurrence-free survival and survival after recurrence, rather than sidedness alone.

Cost-effectiveness of surveillance intervals after curative resection of colorectal cancer.

BACKGROUND: Major guidelines consistently recommend 5 years of postoperative surveillance for patients with colorectal cancer. However, they differ in their recommendations for examination intervals and whether they should vary according to disease stage. Furthermore, there are no reports on the cost-effectiveness of the different surveillance schedules. The objective of this study is to identify the most cost-effective surveillance intervals after curative resection of colorectal cancer. METHODS: A total of 3701 patients who underwent curative surgery for colorectal cancer at the National Cancer Center Hospital were included. A cost-effectiveness analysis was conducted for the five surveillance strategies with reference to the guidelines. Expected medical costs and quality-adjusted life years after colorectal cancer resection were calculated using a state-transition model by Monte Carlo simulation. The incremental cost-effectiveness ratio per quality-adjusted life years gained was calculated for each strategy, with a maximum acceptable value of 43 500-52 200 USD (5-6 million JPY). RESULTS: Stages I, II and III included 1316, 1082 and 1303 patients, respectively, with 45, 140 and 338 relapsed cases. For patients with stage I disease, strategy 4 (incremental cost-effectiveness ratio $26 555/quality-adjusted life year) was considered to be the most cost-effective, while strategies 3 ($83 071/quality-adjusted life year) and 2 ($289 642/quality-adjusted life year) exceeded the threshold value. In stages II and III, the incremental cost-effectiveness ratio for strategy 3 was the most cost-effective option, with an incremental cost-effectiveness ratio of $18 358-22 230/quality-adjusted life year. CONCLUSIONS: In stage I, the cost-effectiveness of intensive surveillance is very poor and strategy 4 is the most cost-effective. Strategy 3 is the most cost-effective in stages II and III.

Real-world treatment costs of first-line treatment for metastatic colorectal cancer: a survey of the JCOG colorectal cancer study group.

BACKGROUND: Although treatment outcomes for metastatic colorectal cancer (mCRC) have dramatically improved over the past few decades, drug costs have also significantly increased. This study aimed to investigate which first-line treatment regimens for mCRC are actually used (frequency) in Japanese practice and at what cost. METHODS: We collected data on patients with mCRC who received first-line treatment at 37 institutions of the Japan Clinical Oncology Group Colorectal Cancer Study Group from July 2021 to June 2022, and calculated the cost of regimens. The cost per month of each regimen was estimated based on standard usage, assuming a patient with a weight of 70 kg and a body surface area of 1.8 m2. We categorized the regimens into very high-cost (≥1 000 000 Japanese yen [JPY]/month), high-cost (≥500 000 JPY/month), and others (<500 000 JPY/month). RESULTS: The study included 1880 participants, 24% of whom were ≥ 75 years. Molecular targeted containing regimens were received by 78% of the patients. The most frequently used regimen was the doublet regimen (fluoropyrimidine with either oxaliplatin or irinotecan) plus bevacizumab (43%), followed by doublet plus cetuximab or panitumumab (21%). The cost of molecular targeted drugs-containing regimens (ranging from 85 406 to 843 602 JPY/month) is much higher than that of only cytotoxic drug regimens (ranging from 17 672 to 51 004 JPY/month). About 16% received high-cost treatments that included panitumumab-containing regimens and pembrolizumab (17% of patients aged ≤74 years and 11% of patients aged ≥75 years). CONCLUSION: About 16% of mCRC patients received first-line treatment with regimens costing >500 000JPY/month, and molecular targeted drugs being the main drivers of cost.

Short- and long-term outcomes of surgical treatment for inguinal lymph node metastasis in rectal and anal canal adenocarcinoma.

AIM: The significance of lymphadenectomy and its indications in patients with inguinal lymph node metastasis (ILNM) of anorectal adenocarcinoma is unclear. This study aimed to clarify the surgical outcomes and prognostic factors of inguinal lymphadenectomy for ILNM. METHOD: This study included patients who underwent surgical resection for ILNM of rectal or anal canal adenocarcinoma with pathologically positive metastases between 1997 and 2011 at 20 participating centres in the Study Group for Inguinal Lymph Node Metastasis from Colorectal Cancer organized by the Japanese Society for Cancer of the Colon and Rectum. Clinicopathological characteristics and short- and long-term postoperative outcomes were retrospectively analysed. RESULTS: In total, 107 patients were included. The primary tumour was in the rectum in 57 patients (53.3%) and in the anal canal in 50 (46.7%). The median number of ILNMs was 2.34. Postoperative complications of Clavien-Dindo Grade III or higher were observed in five patients. The 5-year overall survival rate was 38.8%. Multivariate analysis identified undifferentiated histological type (P < 0.001), pathological venous invasion (P = 0.01) and pathological primary tumour depth T0-2 (P = 0.01) as independent prognostic factors for poor overall survival. CONCLUSION: The 5-year overall survival after inguinal lymph node dissection was acceptable, and it warrants consideration in more patients. Further larger-scale studies are needed in order to clarify the surgical indications.

Short- and long-term outcomes of robotic and laparoscopic surgery in rectal cancer: a propensity score-matched analysis.

PURPOSE: The relative benefits of robotic surgery and laparoscopic surgery are controversial in rectal cancer. This study compared the short- and long-term outcomes of robotic surgery with those of laparoscopic surgery in patients with rectal cancer using propensity score analysis. METHODS: This study analyzed consecutive patients who underwent minimally invasive surgery for stage I-III rectal cancer between April 2014 and October 2020. After propensity score matching (PSM), short-term outcomes, relapse-free survival, and overall survival were compared between the robotic surgery (RS) group and the laparoscopic surgery (LS) group. RESULTS: During the study period, 251 patients underwent laparoscopic surgery and 193 underwent robotic surgery. PSM resulted in 160 matched pairs (After PSM, the percentages of patients with stage I, II, and III disease were respectively 56%, 19%, and 24% in the LS group and 49%, 23%, and 28% in the RS group (P = 0.462). Median operation time was 239 min in the LS group and 284 min in the RS group (P = 0.001). The C-reactive protein level on postoperative day 3 was significantly lower in the RS group (4.63 mg/mL vs. 5.86 mg/mL, P = 0.013). Postoperative complications, including ileus and Clavien-Dindo grade II or higher complications, were 6% vs. 1% (P = 0.006) and 21% vs. 12% (P = 0.024) in the LS and RS groups, respectively. The 5-year relapse-free survival rate was 88.5% in the LS group and 90.5% in the RS group (P = 0.525); the respective 5-year overall survival rates were 97.3 and 93.8% (P = 0.283). The 5-year cumulative local and distant recurrence rates were 3.3% vs. 3.3% (P = 0.665) and 9.7% vs. 7.7% (P = 0.464) in the LS and RS groups, respectively CONCLUSION: Robotic surgery can be a feasible treatment modality for rectal cancer, with lower frequencies of postoperative ileus and Clavien-Dindo grade II or higher complications than laparoscopic surgery and no difference in long-term outcomes.

Clinical utility of sarcopenia dynamics assessed by psoas muscle volume in patients with colorectal cancer.

BACKGROUND: Sarcopenia affects the postoperative prognosis of patients with colorectal cancer (CRC). Recently, it has become possible to measure psoas volume from computed tomography images, and an index called psoas volume index (PVI) has been reported. However, it is unclear whether the dynamics of PVI before and after surgery is associated with clinical outcomes after CRC surgery. This study aimed to evaluate the association between pre- and postoperative PVI dynamics and clinical outcomes after CRC surgery. METHODS: This study analyzed 1115 patients diagnosed with primary CRC and operated on for treatment between January 2014 and December 2017. Sarcopenia was defined as PVI below the lowest tertile in the preoperative assessment for each sex. The overall population was divided into four groups according to the dynamics of sarcopenia from preoperative to postoperative: group 1 (pre-to postoperative sarcopenia), group 2 (preoperative nonsarcopenia to postoperative sarcopenia), group 3 (pre-to postoperative nonsarcopenia), and group 4 (pre-to postoperative nonsarcopenia). RESULTS: Based on pre- and postoperative sarcopenia dynamics, 343 patients (29.7%) were classified into group 1, 105 patients (9.1%) into group 2, 42 patients (3.6%) into group 3, and 665 patients (57.6%) into group 4. Comparison of overall survival (OS) by the Kaplan-Meier method showed that Group 2 tended to have the worst prognosis (p = 0.007). Multivariate analysis showed an increased OS risk in Group 2 in sarcopenia dynamics (Hazard ratio: 2.103, 95% CI: 1.202-3.681, p = 0.009). CONCLUSIONS: Sarcopenia dynamics using PVI is an independent prognostic predictor of OS in patients with CRC.

RAS mutation associated with short surgically controllable period in colorectal liver metastases: a retrospective study.

BACKGROUND: The prognostic implications of the RAS status in colorectal cancer liver metastasis (CRLM) remain unclear. This study investigated the prognostic significance of RAS status after curative hepatectomy, focusing on surgical controllability. METHODS: This retrospective study included liver-only CRLM patients who underwent the first hepatectomy between 2015 and 2022 at the National Cancer Center Hospital. Recurrence-free survival (RFS), surgically controllable period (SCP), and overall survival (OS) were compared between RAS wild-type (RAS-wt) and mutant (RAS-mt) patients. Multivariate analyses were conducted to identify independent prognostic factors for each outcome and independent risk factors for less than 1 year SCP. RESULTS: A total of 150 patients were evaluated, comprising 63 patients with RAS-mt status. There was no significant difference in RFS between RAS-mt and RAS-wt (7.00 vs. 8.03 months, p = 0.48). RAS-mt patients exhibited worse SCP (11.80 vs.21.13 months, p < 0.001) and OS (44.03 vs. 70.03 months, p < 0.001) compared to RAS-wt. Multivariate analysis identified RAS-mt as an independent prognostic factor for both OS (hazard ratio [HR]: 3.37, p < 0.001) and SCP (HR: 2.20, p < 0.001), and as an independent risk factor for less than 1 year of SCP (odds ratio, 2.31; p = 0.03). CONCLUSIONS: CRLM with RAS mutations should be considered for strict surgical indications with preoperative chemotherapy and thorough examination, considering the possibility of short SCP.

Proportions and characteristics of interval cancer in annual fecal immunochemical test screening and postcolonoscopy colorectal cancer: Results from a Japanese multicenter prospective study using questionnaires, the C-DETECT study.

OBJECTIVES: There are several types of colorectal cancer (CRC) according to the detection methods and intervals, including interval CRC (iCRC) and postcolonoscopy CRC (PCCRC). We aimed to examine their proportions and characteristics. METHODS: We conducted a multicenter prospective study using questionnaires in Japan ("C-DETECT study"), in which differences in CRC characteristics according to detection methods and intervals were examined from consecutive adult patients. Because the annual fecal immunochemical test (FIT) was used in population-based screening, the annual FIT-iCRC was assessed. RESULTS: In total, 1241 CRC patients (1064 with invasive CRC) were included. Annual FIT-iCRC (a), 3-year PCCRC (b), and CRC detected within 1 year after a positive FIT with noncompliance to colonoscopy (c) accounted for 4.5%, 7.0%, and 3.9% of all CRCs, respectively, and for 3.9%, 5.4%, and 4.3% of invasive CRCs, respectively. The comparison among these (a, b, c) and other CRCs (d) demonstrated differences in the proportions of ≥T2 invasion ([a] 58.9%, [b] 44.8%, [c] 87.5%, [d] 73.0%), metastasis ([a] 33.9%, [b] 21.8%, [c] 54.2%, [d] 43.9%), right-sided CRC ([a] 42.9%, [b] 40.2%, [c] 18.8%, [d] 28.6%), and female sex ([a] 53.6%, [b] 49.4%, [c] 27.1%, [d] 41.6%). In metastatic CRC, (a) and (b) showed a higher proportions of BRAF mutations ([a] [b] 12.0%, [c] [d] 3.1%). CONCLUSIONS: Annual FIT-iCRC and 3-year PCCRC existed in nonnegligible proportions. They were characterized by higher proportions of right-sided tumors, female sex, and BRAF mutations. These findings suggest that annual FIT-iCRC and 3-year PCCRC may have biological features different from those of other CRCs.

[Health Economic Evaluation of Surgical Treatment for Cancer].

Conducting"health economic evaluation"is one of the most important issues for the efficient allocation of healthcare costs. Although the Central Social Insurance Medical Council in Japan(Chuikyo)introduced a cost-effectiveness evaluation system for drugs and medical devices in 2019, there are no reports of the system being officially utilized for medical procedures, including surgical treatments. Because it is often required to provide the best possible treatment to save lives, cancer care is an area where it is difficult to adapt"health economic evaluation". In addition, surgical treatment is more invasive than medical checkups or drug therapy, and complications and hospitalization costs vary widely from case to case, so the cooperation of the medical affairs department is essential in examining medical costs for health economic evaluation. Although QOL surveys are important for the evaluation of invasiveness, there are almost no large-scale studies that reflect the actual conditions of treatment, and none for Japanese and for patients undergoing cancer treatment. It is essential to conduct QOL surveys for future health economic evaluation. We will explain"health economic evaluation"of surgical treatment for cancer, using as examples the results of medical technology evaluation of surgical techniques that we have reviewed. In considering the"health economic evaluation"of surgical treatment for cancer, the medical cost and QOL surveys were considered to be particularly important. We look forward to future research.

Prognostic Role for Primary Tumor Location in Patients With Colorectal Liver Metastases: A Comparison of Right-Sided Colon, Left-Sided Colon, and Rectum.

BACKGROUND: Although right-sided colon cancer is increasingly recognized as having a worse prognosis than left-sided colorectal cancer for colorectal liver metastases, little is known about the differences between the left-sided colon and rectum. OBJECTIVE: This study evaluated the prognostic value of primary tumor location in patients with colorectal liver metastases by examining the left-sided colon and rectum separately. DESIGN: This was a retrospective study from 2003 to 2017. SETTINGS: The study was conducted in a National Cancer Center Hospital. PATIENTS: The study cohort included 489 patients with colorectal liver metastases from right-sided colon cancer ( n = 119, 24%), left-sided colon cancer ( n = 251, 51%), or rectal cancer ( n = 119, 24%) who underwent hepatic resection. MAIN OUTCOME MEASURES: Primary outcomes were relapse-free survival and overall survival. RESULTS: Five-year relapse-free survival rates for patients with right-sided colon cancer, left-sided colon cancer, and rectal cancer were 28.6%, 34.1%, and 26.4%, and 5-year overall survival rates were 53.9%, 70.3%, and 60.8%. Multivariable analysis revealed significant differences in relapse-free survival and overall survival between left-sided colon cancer and rectal cancer (relapse-free survival: HR = 1.37, p = 0.03; overall survival: HR = 1.49, p = 0.03) and between left-sided colon cancer and right-sided colon cancer (relapse-free survival: HR = 1.39, p = 0.02; overall survival: HR = 1.60, p = 0.01), but not between right-sided colon cancer and rectal cancer. In patients with recurrence ( n = 325), left-sided colon cancer had the lowest multiple-site recurrence rate and the highest surgical resection rate for recurrence (left-sided colon cancer, 20%/46%; right-sided colon cancer, 32%/30%; rectal cancer, 26%/39%). LIMITATIONS: This study was retrospective in design. CONCLUSIONS: Rectal cancer was associated with worse relapse-free survival and overall survival compared with left-sided colon cancer in patients with colorectal liver metastases who underwent hepatic resection. Our findings suggest that the left-sided colon and rectum should be considered distinct entities in colorectal liver metastases. See Video Abstract at http://links.lww.com/DCR/B882 . PAPEL PRONSTICO DE LA UBICACIN DEL TUMOR PRIMARIO EN PACIENTES CON METSTASIS HEPTICAS COLORRECTALES UNA COMPARACIN ENTRE COLON DERECHO, COLON IZQUIERDO Y RECTO: ANTECEDENTES:Aunque se reconoce cada vez más que el cáncer de colon del lado derecho tiene un peor pronóstico que el cáncer colorrectal del lado izquierdo para las metástasis hepáticas colorrectales, se sabe poco acerca de las diferencias entre el recto y el colon del lado izquierdo.OBJETIVO:Este estudio evaluó el valor pronóstico de la ubicación del tumor primario en pacientes con metástasis hepáticas colorrectales examinando el recto y el colon del lado izquierdo por separado.DISEÑO:Este fue un estudio retrospectivo de 2003 a 2017.ENTORNO CLÍNICO:El estudio se llevó a cabo en un Hospital del Centro Nacional de Cáncer.PACIENTES:La cohorte del estudio incluyó a 489 pacientes con metástasis hepáticas colorrectales de cáncer de colon del lado derecho (n = 119, 24%), cáncer de colon del lado izquierdo (n = 251, 51%) o cáncer de recto (n = 119, 24%). %) que fueron sometidos a resección hepática.PRINCIPALES MEDIDAS DE VALORACIÓN:Los resultados primarios fueron la supervivencia sin recaídas y la supervivencia general.RESULTADOS:Las tasas de supervivencia sin recaída a cinco años para los pacientes con cáncer de colon derecho, cáncer de colon izquierdo y cáncer de recto fueron del 28,6%, 34,1%, y 26,4%, respectivamente, y las tasas de supervivencia general a los 5 años fueron del 53,9%, 70,3%, y 60,8%, respectivamente. El análisis multivariable reveló diferencias significativas en la supervivencia sin recaída y la supervivencia general entre el cáncer de colon izquierdo y el cáncer de recto (supervivencia sin recaída: HR = 1,37, p = 0,03; supervivencia general: HR = 1,49, p = 0,03) y entre el cáncer de colon izquierdo y el cáncer de colon del lado derecho (supervivencia libre de recaídas: HR = 1,39, p = 0,02; supervivencia global: HR = 1,60, p = 0,01), pero no entre el cáncer de colon del lado derecho y el cáncer de recto. En pacientes con recurrencia (n = 325), el cáncer de colon izquierdo tuvo la tasa de recurrencia en sitios múltiples más baja y la tasa de resección quirúrgica más alta por recurrencia (cáncer de colon izquierdo, 20%/46%; cáncer de colon derecho, 32%/30%; cáncer de recto, 26%/39%).LIMITACIONES:Este estudio fue de diseño retrospectivo.CONCLUSIONES:El cáncer de recto se asoció con una peor supervivencia sin recaída y una supervivencia general peor en comparación con el cáncer de colon izquierdo en pacientes con metástasis hepáticas colorrectales que se sometieron a resección hepática. Nuestros hallazgos sugieren que el colon y el recto del lado izquierdo deben considerarse entidades distintas en las metástasis hepáticas colorrectales. Consulte Video Resumen en http://links.lww.com/DCR/B882 . (Tradducción-Dr. Ingrid Melo ).

A randomized phase II study comparing preoperative mFOLFOX6 versus FOLFOXIRI for locally advanced colon cancer: JCOG2006.

The prognosis of locally advanced colon cancer (LACC) with surgical resection followed only by adjuvant chemotherapy is poor. Preoperative chemotherapy for LACC patients with risk factors such as cT4bN+ or cT3-4aN2-3 has attracted attention. Here, the authors describe the rationale and design of JCOG2006, a randomized phase II study comparing preoperative chemotherapy with mFOLFOX6 versus FOLFOXIRI for LACC. Their efficacy and safety are evaluated and a determination of which is the more promising treatment will be conducted in a subsequent phase III trial. A total of 86 patients will be accrued from 44 institutions over 2 years. The primary end point is the proportion of patients with a Tumor Regression Score of 0-2, and secondary end points include overall survival, response rate and adverse events. Clinical Trial Registration: jRCTs031210365 (https://jrct.niph.go.jp/).

Phase II biomarker identification study of anti-VEGF agents with FOLFIRI for pretreated metastatic colorectal cancer.

Chemotherapy plus antiangiogenic agents, including bevacizumab, ramucirumab and aflibercept, is a standard second-line treatment for patients with metastatic colorectal cancer, but which specific agents should be selected is ambiguous due to a lack of clear evidence from prospective studies. Previous reports have suggested ramucirumab and aflibercept could be more effective than bevacizumab in patients with high VEGF-D and high VEGF-A, respectively. JCOG2004 is a three-arm, randomized, phase II study to identify predictive biomarkers for these agents in patients who have failed first-line treatment. The study will enroll 345 patients from 52 institutions for 2 years, with progression-free survival in high VEGF-D (bevacizumab vs ramucirumab) and high VEGF-A (bevacizumab vs aflibercept) serving as the primary end point. Clinical Trial Registration: jRCTs031220058 (www.jrct.niph.go.jp).

Lateral pelvic lymph node metastasis in T2 low rectal cancer: is TME alone sufficient for cure?

BACKGROUND: Some patients with even T2 low rectal cancer are known to develop lateral pelvic lymph node metastasis. This study aimed to investigate real-world evidence regarding lateral nodal metastasis on T2 low rectal cancer treatment. METHODS: Consecutive patients with pathological T2 low rectal adenocarcinoma who underwent curative-intent surgery between January 2007 and December 2015 at two Japanese cancer centres dedicated to lateral pelvic lymph node dissection were identified and included in the analysis. Lateral pelvic lymph node metastasis was defined as pathologically confirmed metastatic lateral pelvic lymph node or lateral-local recurrence after primary surgery. RESULTS: A total of 215 consecutive patients, including 101 and 114 patients who did and did not undergo bilateral lateral pelvic lymph node dissection, were included in the analysis. Overall, 19 (8.8%) patients had lateral pelvic lymph node metastasis, including 13 with pathologically confirmed metastatic lateral pelvic lymph node and six with lateral-local recurrence. A total of 10 (4.7%) patients had local recurrence, including six with lateral-local recurrence, two with central-local recurrence and two with anastomotic recurrence. Five/7-year cumulative risks of lateral-local recurrence in patients with and without lateral pelvic lymph node dissection were 1.1/1.1% and 3.9/5.2%, respectively. CONCLUSION: The problem of the relatively high rate of lateral local recurrence remains in treating T2 low rectal cancer with only total mesorectal excision. The selection of high-risk patients of lateral pelvic lymph node metastasis and the indication of additional treatment in T2 low rectal cancer should be discussed further.

International standardization and optimization group for intersphincteric resection (ISOG-ISR): modified Delphi consensus on anatomy, definition, indication, surgical technique, specimen description and functional outcome.

AIM: Intersphincteric resection (ISR) is an oncologically complex operation for very low-lying rectal cancers. Yet, definition, anatomical description, operative indications and operative approaches to ISR are not standardized. The aim of this study was to standardize the definition of ISR by reaching international consensus from the experts in the field. This standardization will allow meaningful comparison in the literature in the future. METHOD: A modified Delphi approach with three rounds of questionnaire was adopted. A total of 29 international experts from 11 countries were recruited for this study. Six domains with a total of 37 statements were examined, including anatomical definition; definition of intersphincteric dissection, intersphincteric resection (ISR) and ultra-low anterior resection (uLAR); indication for ISR; surgical technique of ISR; specimen description of ISR; and functional outcome assessment protocol. RESULTS: Three rounds of questionnaire were performed (response rate 100%, 89.6%, 89.6%). Agreement (≥80%) reached standardization on 36 statements. CONCLUSION: This study provides an international expert consensus-based definition and standardization of ISR. This is the first study standardizing terminology and definition of deep pelvis/anal canal anatomy from a surgical point of view. Intersphincteric dissection, ISR and uLAR were specifically defined for precise surgical description. Indication for ISR was determined by the rectal tumour's maximal radial infiltration (T stage) below the levator ani. A new surgical definition of T3isp was reached by consensus to define T3 low rectal tumours infiltrating the intersphincteric plane. A practical flowchart for surgical indication for uLAR/ISR/abdominoperineal resection was developed. A standardized ISR surgical technique and functional outcome assessment protocol was defined.

A review of 14 cases of perianal Paget's disease: characteristics of anorectal cancer with pagetoid spread.

BACKGROUND: Perianal Paget's disease (PPD) is an intraepithelial invasion of the perianal skin and is frequently associated with underlying anorectal carcinoma. The relatively rare nature of this disease has made it difficult to develop treatment recommendations. This study aims to analyze the clinical and pathological features of perianal Paget's disease (PPD) and to explore rational treatment options and follow-up for this disease. METHODS: The National Cancer Center Hospital database was searched for all cases of perianal Paget's disease diagnosed between 2006 and 2021. In the 14 patients identified, we reviewed the diagnosis, management, and outcomes of adenocarcinoma with pagetoid spread, including suspected or recurrent cases. RESULTS: All 14 cases met the inclusion criteria. The median follow-up period after diagnosis was 4.5 (range, 0.1-13.0) years. Pagetoid spread before initial treatment was suspected in 12 cases (85.7%). Underlying rectal cancer was identified in 6 cases, and no primary tumor was detected in the other 6 cases. Seven patients had recurrent disease, with the median time to recurrence of 34.6 (range, 19.2-81.7) months. The time to the first relapse was 3 months, and that to the second relapse was 6 months. The overall 5-year survival rate was 90.0%. CONCLUSIONS: Endoscopic and radiologic evaluation, as well as immunohistologic examination, should be performed. is to differentiate PPD with and without underlying anorectal carcinoma. The time to first recurrence varies widely, and long-term and regular follow-up for more than 5 years is considered necessary for local recurrence and distant metastasis.

Evaluation of Recurrence Risk After Curative Resection for Patients With Stage I to III Colorectal Cancer Using the Hazard Function: Retrospective Analysis of a Single-institution Large Cohort.

OBJECTIVE: This study aimed to investigate transitions of recurrence hazard and peak recurrence time in patients with nonmetastatic CRC using the hazard function. SUMMARY OF BACKGROUND DATA: A postoperative surveillance period of 5 years is consistent across major guidelines for patients with nonmetastatic CRC, but surveillance intervals differ. Estimates of instantaneous conditional recurrence rate can help set appropriate intervals. METHODS: The study population consisted of 4330 patients with stage I to III CRC who underwent curative resection at the National Cancer Center Hospital between January 2000 and December 2013. Hazard rates of recurrence were calculated using the hazard function. RESULTS: Recurrence rates in patients with stage I, II, and III CRC were 4% (50/1432), 11% (136/1231), and 25% (424/1667), respectively. The hazard curve for stage I was relatively flat and hazard rates were consistently low (<0.0015) for 5 years after surgery. The hazard curve for stage II had a peak hazard rate of 0.0046 at 13.7 months, after which the curve had a long hem to the right. The hazard curve for stage III had an earlier and higher peak than that of stage II (0.0105 at 11.6 months), with a long hem to the right. CONCLUSIONS: Changes in recurrence hazard for CRC patients varied considerably by stage. Our findings suggest that short-interval surveillance might be unnecessary for stage I patients for the first 3 years after surgery, whereas short-interval surveillance for the first 3 years should be considered for stage III patients.

A randomized controlled trial comparing perioperative vs. postoperative mFOLFOX6 for lower rectal cancer with suspected lateral pelvic lymph node metastasis (JCOG1310): a phase II/III randomized controlled trial.

OBJECTIVE: The optimal perioperative chemotherapy for lower rectal cancer with lateral pelvic lymph node metastasis remains unclear. We evaluated the efficacy and safety of perioperative mFOLFOX6 in comparison with postoperative mFOLFOX6 for rectal cancer patients undergoing total mesorectal excision with lateral lymph node dissection. METHODS: We conducted an open label randomized phase II/III trial in 18 Japanese institutions. We enrolled patients with histologically proven lower rectal adenocarcinoma with clinical pelvic lateral lymph node metastasis who were randomly assigned (1:1) to receive postoperative mFOLFOX6 (12 courses of intravenous oxaliplatin [85 mg/m2] with L-leucovorin [200 mg/m2] followed by 5-fluorouracil [400 mg/m2, bolus and 2400 mg/m2, continuous infusion, repeated every 2 weeks]) or perioperative mFOLFOX6 (six courses each preoperatively and postoperatively). The primary endpoint was overall survival (OS). The trial is registered with Japan Registry of Clinical Trials, number jRCTs031180230. RESULTS: Between May 2015, and May 2019, 48 patients were randomized to the postoperative arm (n = 26) and the perioperative arm (n = 22). The trial was terminated prematurely due to poor accrual. The 3-year OS in the postoperative and perioperative groups were 66.1 and 84.4%, respectively (HR 0.58, 95% CI [0.14-2.45], one-sided P = 0.23). The pathological complete response rate in the perioperative group was 9.1%. Grade 3 postoperative surgical complications were more frequently observed in the perioperative arm (50.0 vs. 12.0%). One treatment-related death due to sepsis from pelvic infection occurred in the postoperative group. CONCLUSIONS: Perioperative mFOLFOX6 may be an insufficient treatment to improve survival of lower rectal cancer with lateral pelvic lymph node metastasis.

Challenges needed to be overcome in multi-institutional surgical trials: accumulated experience in the JCOG Colorectal Cancer Study Group (CCSG).

JCOG-CCSG has been conducting several surgical trials and experienced several challenges. The first point is the appropriate timing of conducting the trial. Once a certain number of surgeons acquire the new technique and its utility is accepted, it suddenly becomes difficult to maintain 'equipoise' between the standard and new treatment, which may lead to poor patient accrual. Smooth preparation and commencement of the trial at an appropriate timing is necessary for its success. Second is the appropriate quality assurance of surgery. High-level quality assurance will strengthen the comparability of randomized control trials and minimize the heterogeneity among hospitals. On the other hand, it may impair the generalizability of the trial. Large observational studies help to bridge the gap of heterogeneity among hospitals. Third is the selection of an appropriate endpoint. Overall survival (OS) is the gold-standard primary endpoint; however, the number of events is much less due to more effective treatment. JCOG0212 and JCOG0404 were unable to demonstrate the non-inferiority of omission of lateral lymph node dissection and laparoscopic surgery partly due to a lack of power. Disease-free survival (DFS) is also a promising candidate for primary endpoint, but as in JCOG0603, special attention must be paid when DFS does not correlate with OS. Although careful discussion is required because the precision of the hazard ratio depends on the number of events, an alternative population-level summary of variables, including restricted mean survival time, can be considered as the primary endpoint. Future surgical trials should be planned considering these points.