Evaluation of anorectal function using real-time tissue elastography before and after preoperative chemoradiotherapy.

PURPOSE: This study aimed to clarify the relationship between changes in elasticity and anorectal function before and after chemoradiotherapy. METHODS: This is a single-center prospective cohort study (Department of Surgical Oncology, The University of Tokyo). We established a technique to quantify internal anal sphincter hardness as elasticity using transanal ultrasonography with real-time tissue elastography. Twenty-seven patients with post-chemoradiotherapy rectal cancer during 2019-2022 were included. Real-time tissue elastography with transanal ultrasonography was performed before and after chemoradiotherapy to measure internal anal sphincter hardness as "elasticity" (hardest (0) to softest (255); decreased elasticity indicated sclerotic changes). The relationship between the increase or decrease in elasticity pre- and post-chemoradiotherapy and the maximum resting pressure, maximum squeeze pressure, and Wexner score were the outcome measures. RESULTS: A decrease in elasticity was observed in 16/27 (59.3%) patients after chemoradiotherapy. Patients with and without elasticity decrease after chemoradiotherapy comprised the internal anal sphincter sclerosis and non-sclerosis groups, respectively. The maximum resting pressure post-chemoradiotherapy was significantly high in the internal anal sphincter sclerosis group (63.0 mmHg vs. 47.0 mmHg), and a majority had a worsening Wexner score (60.0% vs. 18.2%) compared with that of the non-sclerosis group. Decreasing elasticity (internal anal sphincter sclerosis) correlated with a higher maximum resting pressure (r = 0.36); no correlation was observed between the degree of elasticity change and maximum squeeze pressure. CONCLUSION: Internal anal sphincter sclerosis due to chemoradiotherapy may correlate to anorectal dysfunction.

Nutritional Status Indicators Predict Tolerability to Adjuvant Chemotherapy in Patients with Stage II/III Rectal Cancer Undergoing Neoadjuvant Chemoradiotherapy.

INTRODUCTION: Adjuvant chemotherapy (AC) after radical surgery following preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC) is now the standard of care. The identification of risk factors for the discontinuation of AC is important for further improvements in survival. We herein examined the prognostic impact of chemotherapy compliance and its relationship with the prognostic nutritional index (PNI) before surgery. METHODS: A total of 335 stage II-III LARC patients who underwent preoperative CRT between 2003 and 2022 at the University of Tokyo Hospital were retrospectively reviewed. We excluded patients with recurrence during AC and those who had not received AC. The relationship between AC and long-term outcomes and that between PNI values and the duration of AC were examined. RESULTS: Thirty-one patients discontinued AC and 62 continued AC. Recurrence-free survival (RFS) was significantly shorter in patients who discontinued AC (p = 0.0056). The discontinuation of AC was identified as an independent risk factor for RFS (hazard ratio [HR]: 2.24, p = 0.0233). Twenty-one patients were classified as having low PNI (less than 40), which correlated with an older age, low body mass index, and incomplete AC. Low PNI was an independent risk factor for a shorter duration of AC (HR: 2.53, p = 0.0123). CONCLUSION: The discontinuation of AC was related to poor RFS in patients with LARC undergoing preoperative CRT. Furthermore, a low PNI value was identified as a risk factor for a shorter duration of AC.

Minimally invasive versus open multivisceral resection for rectal cancer clinically invading adjacent organs: a propensity score-matched analysis.

BACKGROUND: Minimally invasive surgery (MIS), such as laparoscopic and robotic surgery for rectal cancer, is performed worldwide. However, limited information is available on the advantages of MIS over open surgery for multivisceral resection for cases clinically invading adjacent organs. PATIENTS AND METHODS: This was a retrospective propensity score-matching study of consecutive clinical T4b rectal cancer patients who underwent curative intent surgery between 2006 and 2021 at the University of Tokyo Hospital. RESULTS: Sixty-nine patients who underwent multivisceral resection were analyzed. Thirty-three patients underwent MIS (the MIS group), while 36 underwent open surgery (the open group). Twenty-three patients were matched to each group. Conversion was required in 2 patients who underwent MIS (8.7%). R0 resection was achieved in 87.0% and 91.3% of patients in the MIS and open groups, respectively. The MIS group had significantly less blood loss (170 vs. 1130 mL; p < 0.0001), fewer Clavien-Dindo grade ≥ 2 postoperative complications (30.4% vs. 65.2%; p = 0.0170), and a shorter postoperative hospital stay (20 vs. 26 days; p = 0.0269) than the open group. The 3-year cancer-specific survival rate, relapse-free survival rate, and cumulative incidence of local recurrence were 75.7, 35.9, and 13.9%, respectively, in the MIS group and 84.5, 45.4, and 27.1%, respectively, in the open group, which were not significantly different (p = 0.8462, 0.4344, and 0.2976, respectively). CONCLUSION: MIS had several short-term advantages over open surgery, such as lower complication rates, faster recovery, and a shorter hospital stay, in rectal cancer patients who underwent multivisceral resection.

Local excision versus radical surgery for anal squamous cell carcinoma: a multicenter study in Japan.

BACKGROUND: The standard treatment for anal squamous cell carcinoma is chemoradiation therapy (CRT), but there is a possibility of over-treatment for early-stage disease. cTisN0 and cT1N0 disease is currently indicated for local excision, but it is unclear whether the indication of local excision can be expanded to cT2N0 disease. METHODS: 126 patients with cTis-T2N0 anal cancer treated at 47 centers in Japan between 1991 and 2015 were included. Patients were first classified into the CRT group and surgical therapy group according to the initial therapy, and the latter was further divided into local excision (LE) and radical surgery (RS) groups. We compared prognoses among the groups, and analyzed risk factors for recurrence after local excision. RESULTS: The CRT group (n = 87) and surgical therapy group (n = 39) showed no difference in relapse-free survival (p = 0.29) and overall survival (p = 0.94). Relapse-free survival curves in the LE (n = 23) and RS groups (n = 16) overlapped for the initial 3 years, but the curve for the LE group went lower beyond (p = 0.33). By contrast, there was no difference in overall survival between the two groups (p = 0.98). In the LE group, the majority of recurrences distributed in locoregional areas, which could be managed by salvage treatments. Muscular invasion was associated with recurrence after local excision (hazard ratio: 22.91, p = 0.011). CONCLUSION: LE may be applied to selected patients with anal cancer of cTis-T2N0 stage. Given the high risk of recurrence in cases with muscular invasion, it may be important to consider close surveillance and additional treatment in such patients.

Enhancement of radiation therapy by indoleamine 2,3 dioxygenase 1 inhibition through multimodal mechanisms.

BACKGROUND: Indoleamine 2,3-dioxygenase 1 (IDO1) is an enzyme that converts tryptophan to kynurenine. IDO1 expression is found not only in tumor cells but also in immune cells and is associated with tumor proliferation and immune responses. IDO1 inhibitors and radiation may cooperatively suppress tumor proliferation through the alterations in the Wnt/ß-catenin pathway, cell cycle, and immune response. We investigated the antitumor effects of combination therapy of an IDO1 inhibitor, 1-methyl tryptophan (1-MT), and radiation on colorectal cancer. METHODS: In vitro experiments were conducted using human and murine colon cancer cell lines (HCT116, HT-29, and Colon26). Cell growth inhibition was assessed using a MTS assay and Clonogenic assay. Cells were cultured for 48 h with or without 500 µM 1-MT after exposure to radiation (4 Gy). Cell cycle effects and modulation of Wnt/ß-catenin pathway were evaluated using western blot analysis, flow cytometry, RT-PCR. Subcutaneous Colon26 tumors in BALB/c mice were treated by oral 1-MT (6 mg/mL) for 2 weeks and/or local radiation (10 Gy/10 fr). Bromodeoxyuridine (BrdU) incorporation in tumor cells and expression of differentiation markers of immune cells were evaluated using immunohistochemistry. RESULTS: 1-MT and a small interfering RNA against IDO1 suppressed proliferation of all cell lines, which was rescued by kynurenine. Clonogenic assay showed that administration of 1-MT improved radiosensitivity by suppressing the Wnt/ß-catenin pathway activated by radiation and enhancing cell cycle arrest induced by radiation. Combination therapy showed a further reduction in tumor burden compared with monotherapies or untreated control, inducing the highest numbers of intratumoral CD3 + and CD8 + T cells and the lowest numbers of Foxp3 + and BrdU-positive tumor cells. CONCLUSIONS: The combination of 1-MT and radiation suppressed colon cancer cells in vitro and in vivo via multiple mechanisms.

Preoperative chemoradiotherapy using tegafur/uracil, oral leucovorin, and irinotecan (TEGAFIRI) followed by oxaliplatin-based chemotherapy as total neoadjuvant therapy for locally advanced rectal cancer: the study protocol for a phase II trial.

BACKGROUND: Total neoadjuvant therapy (TNT) is a novel treatment strategy that is an alternative to preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC). However, an optimal protocol for TNT has not yet been established. The present study will be an open-label, single-arm, single-center trial to develop a new protocol. METHODS: Thirty LARC patients at high risk of distant metastasis will receive CRT consisting of long-course radiation, concurrent with tegafur/uracil, oral leucovorin, irinotecan (TEGAFIRI), followed by mFOLFOX-6 or CAPOX before undergoing surgery. DISCUSSION: Since previous findings showed a high percentage of grade 3-4 adverse events with the TEGAFIRI regimen for CRT and TNT, the primary outcome of this study will be safety and feasibility. Our regimen for CRT consists of the biweekly administration of irinotecan for good patient compliance. The novel combination approach of this treatment may improve the long-term outcomes of LARC. TRIAL REGISTRATION: Japan Registry of Clinical Trials jRCTs031210660.

Clinicopathological Characteristics of Anastomotic Recurrence After Curative Resection for Colorectal Cancer: Comparison With Nonanastomotic Local Recurrences.

BACKGROUND: Anastomotic recurrence is thought to be caused by implantation of tumor cells to the anastomotic line; however, its risk factors and prognostic significance remain unclear. OBJECTIVE: This study aimed to clarify the risk factors for anastomotic recurrence in colorectal cancer and assess the prognosis in comparison to nonanastomotic local recurrence. DESIGN: A single-center retrospective observational study. SETTINGS: The medical records of the study participants were retrospectively collected from the Department of Surgical Oncology at the University of Tokyo Hospital database. PATIENTS: This study included 1584 patients with colorectal cancer who underwent surgical resection between January 2005 and December 2017. We focused on 15 patients who had an anastomotic recurrence. MAIN OUTCOME MEASURES: The main outcome measures were the risk factors of anastomotic recurrence at the primary resection and prognosis data in comparison to that of nonanastomotic local recurrence. RESULTS: There were 15 patients (0.95%) with anastomotic recurrence and 35 (2.21%) with nonanastomotic local recurrence. Univariate analysis revealed that lymph node metastasis and advanced T stage are the risk factors for anastomotic recurrence. The prognosis of patients with anastomotic recurrence was similar to that of those with nonanastomotic local recurrence who underwent resection. LIMITATIONS: The small number of patients with anastomotic recurrence is a major limitation of this study. Additionally, the retrospective study design may have increased the risk of selection bias. CONCLUSIONS: Lymph node metastasis and advanced T stage were associated with anastomotic recurrence. The prognosis of patients with anastomotic recurrence was similar to that with resected nonanastomotic local recurrence. Thus, surveillance should be carefully continued while considering the poor prognosis of patients with anastomotic recurrence. See Video Abstract at http://links.lww.com/DCR/C92 . CARACTERSTICAS CLINICOPATOLGICAS DE LA RECURRENCIA ANASTOMTICA DESPUS DE LA RESECCIN CURATIVA DEL CNCER COLORRECTAL COMPARACIN CON LAS RECURRENCIAS LOCALES NO ANASTOMTICAS: ANTECEDENTES:Se cree que la recurrencia anastomótica es causada por la implantación de células tumorales en la línea anastomótica; sin embargo, los factores de riesgo asociados y el significado en cuanto a pronóstico siguen sin estar claros.OBJETIVO:Este estudio tuvo como objetivo aclarar los factores de riesgo para la recurrencia anastomótica en el cáncer colorrectal y evaluar el pronóstico en comparación con la recurrencia local no anastomótica.DISEÑO:Un estudio observacional retrospectivo de un solo centro.ESCENARIO:Los registros médicos de los participantes del estudio se recopilaron retrospectivamente de la base de datos del Departamento de Cirugía Oncológica del Hospital de la Universidad de Tokio.PACIENTES:Este estudio incluyó a 1584 pacientes con cáncer colorrectal que se sometieron a resección quirúrgica entre enero de 2005 y diciembre de 2017. Nos enfocamos en 15 pacientes que tuvieron recurrencia anastomótica.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron los factores de riesgo de recurrencia anastomótica en la resección primaria y los datos de pronóstico en comparación con la recurrencia local no anastomótica.RESULTADOS:Hubo 15 pacientes (0.95%) con recurrencia anastomótica y 35 (2.21%) con recurrencia local no anastomótica. El análisis univariable reveló que la metástasis en los ganglios linfáticos y el estadio T avanzado son los factores de riesgo para la recurrencia anastomótica. El pronóstico de los pacientes con recidiva anastomótica fue similar al de aquellos con recidiva local no anastomótica sometidos a resección.LIMITACIONES:El pequeño número de pacientes con recurrencia anastomótica es una limitación importante de este estudio. Además, el diseño retrospectivo del estudio puede haber aumentado el riesgo de sesgo de selección.CONCLUSIONES:La metástasis en los ganglios linfáticos y el estadio T avanzado se asociaron con recurrencia anastomótica. El pronóstico de los pacientes con recidiva anastomótica fue similar al de la recidiva local no anastomótica resecada. Por lo tanto, la vigilancia debe continuarse cuidadosamente considerando el mal pronóstico de los pacientes con recurrencia anastomótica. Consulte Video Resumen en http://links.lww.com/DCR/C92 . (Traducción-Dr. Jorge Silva Velazco ).

Prediction of lymph node metastasis of well-differentiated rectal neuroendocrine tumours using multiple diagnostic modalities.

AIM: The preoperative prediction of lymph node metastasis of well-differentiated rectal neuroendocrine tumours is highly desirable and useful in defining surgical indication more accurately. We aimed to evaluate lymph node metastasis in rectal neuroendocrine neoplasms using multiple imaging modalities. METHODS: The clinical records and radiological images of 70 patients with well-differentiated rectal neuroendocrine tumours who received treatment at the University of Tokyo Hospital between 2010 and 2022 were retrospectively analysed. The relationship between evaluation by multiple imaging modalities and pathological lymph node metastasis was analysed. RESULTS: The receiver operating characteristic curves showed that a maximum lymph node diameter ≥4 mm on computed tomography and ≥8 mm on magnetic resonance imaging were the optimal predictive factors for lymph node metastasis. Accumulation in the lymph nodes on somatostatin receptor scintigraphy (P = 0.058) and Delle's findings on colonoscopy (P = 0.014) were also significant predictors of pathological lymph node positivity, and combination of multiple modalities was useful. Pathologically, lymphatic (P = 0.0030)/venous (P = 0.0007) invasion were risk factors for lymph node metastasis. CONCLUSIONS: In addition to pathological risk factors, a combination of multiple radiological imaging modalities is useful for predicting lymph node metastasis in well-differentiated rectal neuroendocrine tumours.

Determination of the positional relationship of the second Houston valve and peritoneal reflection using computed tomographic colonography and magnetic resonance imaging.

PURPOSE: The second Houston valve is used as a surrogate for estimating the position of the peritoneal reflection; however, the concordance between the positions of the valve and peritoneal reflection has not been investigated. This study aimed to clarify this positional relationship. METHODS: The second Houston valve and peritoneal reflection positions were assessed using tomographic colonography and magnetic resonance imaging. In total, 117 patients were enrolled in this study. RESULTS: The positions of the second Houston valve and peritoneal reflection were nearly concordant, although the space between them ranged from - 20.7 to 33.9 mm. A peritoneal reflection located further from the anal verge than the second Houston valve was defined as a shallow peritoneal reflection. Male sex, high body weight, and a high body mass index were significantly correlated with a shallower peritoneal reflection, as determined by a univariate analysis (sex: P = 0.0138, weight: P = 0.0097, body mass index: P = 0.0311). A multivariate analysis revealed a significantly shallower peritoneal reflection in males than in females (odds ratio: 2.75, 95% confidence interval: 1.15-6.56, P = 0.023). CONCLUSIONS: The second Houston valve located near the peritoneal reflection can be a useful surrogate marker for estimating its position. In relatively heavy males, the peritoneal reflection is located more cranially than the second Houston valve.

Surgical outcomes of robotic, laparoscopic, and open low anterior resection after preoperative chemoradiotherapy for patients with advanced lower rectal cancer.

PURPOSE: We investigated the surgical outcomes of robotic low anterior resection (LAR) for lower rectal cancer after preoperative chemoradiotherapy (pCRT). METHODS: A total of 175 patients with lower rectal cancer who underwent LAR after pCRT between 2005 and 2020 were stratified into open (OS, n = 65), laparoscopic (LS, n = 64), and robotic surgery (RS, n = 46) groups. We compared the clinical, surgical, and pathological results among the three groups. RESULTS: The RS and LS groups had less blood loss than the OS group (p < 0.0001). The operating time in the RS group was longer than in the LS and OS groups (p < 0.0001). The RS group had a significantly longer mean distal margin than the LS and OS groups (25.4 mm vs. 20.7 mm and 20.3 mm, respectively; p = 0.026). There was no significant difference in the postoperative complication rate among the groups. The local recurrence rate in the RS group was comparable to those in the LS and OS groups. CONCLUSION: Robotic LAR after pCRT was performed safely for patients with advanced lower rectal cancer. It provided a longer distal margin and equivalent local control rates.

Benefits of a laparoscopic approach for second colorectal resection after colectomy or proctectomy -a retrospective study.

BACKGROUND: A laparoscopic approach generally provides several benefits in patients who undergo colon or rectal surgery without jeopardizing oncological outcomes. However, there is a paucity of studies on comparative outcomes of laparoscopic versus open approaches for second primary colorectal lesions after colectomy or proctectomy. METHODS: From patients with colorectal disease who underwent surgery between 2008 and 2022 at our hospital, we collected 69 consecutive patients who had previous colorectal surgery for this retrospective study. Based on the second surgery approach (laparoscopic or open), patients were classified into the Lap (n = 37) or Op group (n = 32). Patients' baseline data and perioperative and postoperative outcomes were compared between the two groups. RESULTS: Four patients (11%) of the Lap group needed conversion to laparotomy. The intraoperative blood loss was lower in the Lap group than the Op group (median: 45 ml vs. 205 ml, p = 0.001). The time to first bowel movement was shorter in the Lap group than the Op group (median: 2.8 days vs. 3.6 days, p = 0.007). The operative time, frequencies of postoperative morbidities, and overall survival did not differ between the two groups. CONCLUSION: Laparoscopic surgery appeared feasible and beneficial for selected patients undergoing second colorectal resection after colectomy or proctectomy regarding blood loss and bowel function recovery without affecting other outcomes.

Prognoses in Pathologically Confirmed T1 Lower Rectal Cancer Patients with or without Preoperative Therapy: An Analysis Using the Surveillance, Epidemiology, and End Results Database.

INTRODUCTION: Preoperative chemoradiotherapy (CRT) is the standard therapy for downstaging in locally advanced lower rectal cancer. However, it remains unclear whether rectal cancers downstaged by preoperative therapy show similar prognoses to those of the same stage without preoperative therapy. We previously demonstrated that preoperative CRT did not affect prognosis of rectal cancer with pathological T1N0 (pT1N0) stage in a single institute. Here, using a larger dataset, we compared prognoses of (y)pT1 rectal cancer stratified by the use of preoperative therapy and analyzed prognostic factors. METHODS: Cases of pT1N0 rectal cancer, registered between 2004 and 2016, were extracted from the Surveillance, Epidemiology, and End Results database. Patients were categorized as the "ypT1 group" if they had undergone preoperative therapy before surgery or as the "pT1 group" if they had undergone surgery alone. Overall survival (OS) and cancer-specific survival (CSS) between these groups of patients were compared. Factors associated with CSS and OS were identified by univariate and multivariate analyses. RESULTS: Among 3,757 eligible patients, ypT1 and pT1 groups comprised 720 and 3,037 patients, respectively. While ypT1 patients showed poorer CSS than ypT1 patients, there was no significant difference in OS. Preoperative therapy was not an independent prognostic factor for CSS or OS. Multivariate analysis identified age and histological type as significant factors associated with CSS. Sex, age, race, and number of lymph nodes dissected were identified as significant factors associated with OS. CONCLUSIONS: Prognosis among patients with (y)p T1N0 rectal cancer was similar irrespective of whether they underwent preoperative therapy, which is consistent with our previous observations.

Clinical impact of primary tumor sidedness and sex on unresectable post-recurrence survival in resected pathological stage II-III colorectal cancers: a nationwide multicenter retrospective study.

BACKGROUND: Several studies have demonstrated that right-sided tumors have poorer prognosis than left-sided tumors in patients with unresectable colorectal cancer (CRC). The predictive ability of the tumor sidedness in CRC treated with chemotherapy in each sex is unclear. METHODS: Subjects were 964 unresectable recurrent patients treated with chemotherapy with stage II-III CRC after curative resection between 2004 and 2012. Post-recurrence cancer-specific survival (CSS) for each sex was examined. RESULTS: Patients were 603 males (222 right-side tumors (cecum to transverse colon) and 381 left-sided tumors (descending colon to rectum)), and 361 females (167 right-side tumors and 194 left-sided tumors). Right-sided tumors developed peritoneal recurrences in males and females. Left-sided tumors were associated with locoregional recurrences in males and with lung recurrences in females. Right-sided tumors were associated with shorter post-recurrence CSS in both sexes. In males, multivariate analyses showed that right-sided tumors were associated with shorter post-recurrence CSS (HR: 1.53, P < 0.0001) together with the presence of regional lymph node metastasis histopathological type of other than differentiated adenocarcinoma, the recurrence of liver only, the recurrence of peritoneal dissemination only, and relapse-free interval less than one-year. In females, multivariate analyses showed that right-sided tumors were associated with shorter post-recurrence CSS (HR: 1.50, P = 0.0019) together with advanced depth of invasion, the presence of regional lymph node metastasis, and recurrence of liver only. CONCLUSIONS: Primary tumor sidedness in both sexes in unresectable recurrent CRC patients treated with chemotherapy may have prognostic implications for post-recurrence CSS.

Poor nutrition and sarcopenia are related to systemic inflammatory response in patients with rectal cancer undergoing preoperative chemoradiotherapy.

BACKGROUND: Preoperative chemoradiotherapy (CRT) is the standard therapy for locally advanced rectal cancer (LARC). However, the changes that the patient's physical status during CRT, such as host systemic inflammatory response, nutritional status, and muscle depletion, are still unclear. We evaluated the clinical significance of malnutrition and sarcopenia for patients with LARC undergoing CRT. PATIENTS AND METHODS: Patients with LARC treated with CRT following radical surgery at our institution between 2006 and 2016 (N = 225) were retrospectively analyzed. A new prognostic score (PNSI) was devised based on the prognostic nutritional index (PNI) and the psoas muscle mass index (PMI): patients with malnutrition/sarcopenia were scored 2; patients with one and neither abnormality were scored 1 and 0, respectively. RESULTS: Neutrophil/lymphocyte ratio, monocyte/lymphocyte ratio, and platelet/lymphocyte ratio increased, whereas PNI and PMI decreased after CRT. There were 130, 73, and 22 patients in the PNSI 0, 1, and 2 groups, respectively. Patients with higher PNSI had higher residual tumor size (p = 0.003), yT stage (p = 0.007), ypStage (p < 0.001), post-CRT platelet/lymphocyte ratio (p = 0.027), and post-CRT C-reactive protein/albumin ratio (p < 0.001). Post-CRT PNSI was associated with overall survival and was an independent poor prognosis factor (PNSI 1 to 0, hazard ratio 2.40, p = 0.034, PNSI 2 to 0, hazard ratio 2.66, p = 0.043) together with mesenteric lymph node metastasis, lateral lymph node metastasis, and histology. CONCLUSION: A combined score of post-CRT malnutrition/sarcopenia is promising for predicting overall survival in LARC.

Preoperative sarcopenia is a poor prognostic factor in lower rectal cancer patients undergoing neoadjuvant chemoradiotherapy: a retrospective study.

BACKGROUND: This study aimed to investigate the effect of sarcopenia on the prognosis of advanced lower rectal cancer patients receiving neoadjuvant chemoradiotherapy (CRT). Sarcopenia has been recognized as an adverse factor for surgical outcomes in several malignancies. However, the impact of preoperative sarcopenia on rectal cancer patients receiving CRT is still unknown. METHODS: This retrospective study included cT3-T4 anyN M0 lower rectal cancer patients who underwent CRT followed by R0 resection at our institution between October 2003 and December 2016. CRT consisted of 5-fluorouracil-based oral chemotherapy and long course radiation (50.4 Gy/28 fr). The psoas muscle area at the third lumbar vertebra level was evaluated by computed tomography before and after CRT, and was adjusted by the square of the height to obtain the psoas muscle mass index (PMI). Sarcopenia was defined as the sex-specific lowest quartile of the PMI. We assessed the association between pre- and post-CRT sarcopenia and postoperative prognosis. RESULTS: Among 234 patients, 55 and 179 patients were categorized as sarcopenia and non-sarcopenia patients, respectively. Although post-CRT sarcopenia correlated with residual tumor size, it had no association with other pathological features. The median follow-up period was 72.9 months, and the 5-year DFS and OS were 67.0% and 85.8%, respectively. Multivariate analysis showed that post-CRT sarcopenia was independently associated with poor DFS (HR: 1.76; P = 0.036), OS (HR: 2.01; P = 0.049), and recurrence in the liver (HR: 3.01; P = 0.025). CONCLUSIONS: Sarcopenia is a poor prognostic indicator in lower advanced rectal cancer patients treated with CRT.

Predictive factors of survival of colorectal cancer patients after para-aortic lymph node metastasis.

BACKGROUND: Para-aortic lymph node (PALN) metastasis is an ominous manifestation indicating a poor prognosis in colorectal cancer (CRC) patients; however, some treatments prolong survival. In this study, we investigated predictors of prolonged survival in CRC patients after PALN metastasis. METHODS: We examined 141 patients with CRC that metastasized to the PALNs from CRC with or without extra-PALN metastasis. Among clinicopathological parameters, factors associated with survival after PALN metastasis were identified by multivariate analyses using Cox's proportional hazard models. RESULTS: The mean hemoglobin and albumin values at diagnosis were 12.3 g/dL and 3.7 g/dL, respectively. Rectal cancer was predominant (n = 81). Mutated RAS was detected in 43%. One hundred and four patients had differentiated adenocarcinoma. Patients underwent PALN dissection (n = 11), radiotherapy (n = 6), and systemic therapy (n = 120). Biologics were administered to 95 patients. The median survival time was 29.1 months. On multivariate analysis, independent factors associated with reduced survival after PALN metastasis were low albumin (hazard ratio [HR] 2.33 per -1 g/dL), mutated RAS (HR 2.55), other than differentiated adenocarcinoma (HR 2.75), rectal cancer (HR 3.38 against right-sided colon, and 3.48 against left-sided colon), the presence of extra-PALN metastasis (HR 6.56), and no use of biologics (HR 3.04). CONCLUSIONS: This study revealed that hypoalbuminemia as well as RAS mutation, undifferentiated histology, rectal cancer, other site metastasis, and no use of biologics contribute to poor prognosis in CRC patients with PALN metastasis. Nutritional management may be important for improving survival of these patients.

Computed tomographic colonography versus double-contrast barium enema for the preoperative evaluation of rectal cancer.

PURPOSE: We investigated whether or not computed tomographic colonography (CTC) is a viable alternative to double-contrast barium enema (BE) for a preoperative rectal cancer evaluation. METHODS: The size and distance from the anal canal to the lower or upper tumor borders were laterally measured in 147 patients who underwent CTC and BE. Measurements were grouped into early cancer, advanced, and after chemoradiation therapy (CRT). RESULTS: In the early and advanced cancer groups, all lesions were visualized by BE. In contrast, 3 (7.8%) early and 8 (7.3%) advanced cases, located at the anterior wall near the anal canal, were not visualized by CTC because of liquid level formation. In the CRT group, 16 (23.5%) and 4 (5.8%) cases were not visualized by CTC and BE, respectively. The BE and CTC size measurements were similar among cohorts. However, the distance from the anal canal's superior margin tended to be longer with BE, especially in early cancer. The differences in distance from the anal canal were significantly larger in the early cancer group than in the other two groups (p = 0.0024). CONCLUSION: CTC may be a viable alternative imaging modality in some cases. However, BE should be employed in anterior wall cases near the anal canal and CRT cases.

Vascular anatomy of the splenic flexure: a review of the literature.

Surgical treatment of the transverse colon is difficult because of the many variations of blood vessels. We reviewed the patterns of vascular anatomy and the definition of the vessels around the splenic flexure. We searched the PubMed database for studies on the vascular anatomy of the splenic flexure that were published from January 1990 to October 2020. After screening of full texts, 33 studies were selected. The middle colic arteries were reported to arise independently without forming a common trunk in 8.9-33.3% of cases. The left colic artery was absent in 0-7.5% of cases. The accessory middle colic artery was present in 6.7-48.9% of cases and was present in > 80% of cases without a left colic artery. The reported frequency of Riolan's arch was 7.5-27.8%. The frequency was found to vary widely across studies, partially due to the ambiguous definition of Riolan's arch. A comprehensive preoperative knowledge of the branching patterns of the middle colic artery and left colic artery and the presence of collateral arteries would be helpful in surgery for colon cancer in the splenic flexure.

Identification of Odoribacter splanchnicus bacteremia using MALDI-TOF mass spectrometry and 16S rRNA sequencing: A case report.

Odoribacter splanchnicus was recently reclassified from the genus Bacteroides. We present the first case of Odoribacter splanchnicus bacteremia following appendicitis. The species was identified using MALDI-TOF mass spectrometry and later confirmed with 16S rRNA sequencing. The patient was successfully managed with surgery and antibiotic administration for two weeks.

Hazard function analysis of metastatic recurrence after colorectal cancer surgery-A nationwide retrospective study.

BACKGROUND AND OBJECTIVES: An optimal postoperative surveillance protocol for colorectal cancer (CRC) is dependent on understanding the time line of recurrence. By hazard function analysis, this study aimed at evaluating the time of occurrence of metastasis. METHODS: A total of 21,671 Stage I-III colon cancer patients were retrospectively included from the Japanese study group for postoperative follow-up of colorectal cancer database. RESULTS: The 5-year incidence by metastasized organ was 6.3% for liver (right:left = 5.5%:7.0%, p = .0067), 6.0% for lung (right:left:rectum = 3.7%:4.4%:8.8%, p = 7.05E-45), and 2.0% for peritoneal (right:left:rectum = 3.1%:2.0%:1.2%, p = 1.29E-12). The peak of liver metastasis hazard rate (HR) (0.67 years) was earlier and higher than those of other metastases. The peak HR tended to be delayed in early stage CRCs (0.91, 0.76, and 0.52 years; for Stages I, II, and III, respectively). When analyzed as per the primary tumor location (right-sided, left-sided, and rectum), the peak HR for lung metastasis was twice as high for rectal cancer than for colon cancer, and peritoneal metastasis had a high HR in right-sided colon cancers. CONCLUSION: The time course for the risk of recurrence in various metastatic organs based on the primary tumor site was clearly visualized in this study. This will aid in individualizing postoperative surveillance schedules.