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.

Long-term outcomes of additional surgery after endoscopic resection versus primary surgery for T1 colorectal cancer.

INTRODUCTION: There is considerable concern about whether endoscopic resection (ER) prior to additional surgery (AS) for T1 colorectal cancer (CRC) has oncologically potential adverse effects. Therefore, this study aimed to compare the long-term outcomes, including overall survival (OS), of patients treated with AS after ER versus primary surgery (PS) for T1 CRC using a propensity score-matched analysis from a large observational study. METHODS: This study investigated 6105 patients with T1 CRC treated with either ER or surgical resection between 2009 and 2016 at 27 high-volume Japanese institutions, with those undergoing surgery alone included in the PS group and those undergoing AS after ER included in the AS group. Propensity score matching was used for long-term outcomes of mortality and recurrence analysis. RESULTS: After propensity score matching, 1219 of 2438 patients were identified in each group. The 5-year OS rates in the AS and PS groups were 97.1% and 96.0%, respectively (hazard ratio: 0.72, 95% confidence interval [CI]: 0.49-1.08), indicating the non-inferiority of the AS group. Moreover, 32 patients (2.6%) in the AS group and 24 (2.0%) in the PS group had recurrences, with no significant difference between the two groups (odds ratio: 1.34, 95% CI: 0.76-2.40, p = 0.344). DISCUSSION: ER prior to AS for T1 CRC had no adverse effect on patients' long-term outcomes, including the 5-year OS rate. ER is a viable first-line treatment option for endoscopically resectable T1 CRC.

Treatment Decision for Locally Resected T1 Colorectal Carcinoma-Verification of the Japanese Guideline Criteria for Additional Surgery Based on Long-Term Clinical Outcomes.

INTRODUCTION: To verify the value of the pathological criteria for additional treatment in locally resected pT1 colorectal carcinoma (CRC) which have been used in the Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines since 2009. METHODS: We enrolled 4,719 patients with pT1 CRC treated at 27 institutions between July 2009 and December 2016 (1,259 patients with local resection alone [group A], 1,508 patients with additional surgery after local resection [group B], and 1,952 patients with surgery alone [group C]). All 5 factors of the JSCCR guidelines (submucosal resection margin, tumor histologic grade, submucosal invasion depth, lymphovascular invasion, and tumor budding) for lymph node metastasis (LNM) had been diagnosed prospectively. RESULTS: Any of the risk factors were present in 3,801 patients. The LNM incidence was 10.3% (95% confidence interval 9.3-11.4) in group B/C patients with risk factors, whereas it was 1.8% (95% confidence interval 0.4-5.2) in those without risk factors ( P < 0.01). In group A, the incidence of recurrence was 3.4% in patients with risk factors, but it was only 0.1% in patients without risk factors ( P < 0.01). The disease-free survival rate of group A patients classified as risk positive was significantly worse than those of groups B and C patients. However, the 5-year disease-free survival rate in group A patients with no risk was 99.2%. DISCUSSION: Our large-scale real-world multicenter study demonstrated the validity of the JSCCR criteria for pT1 CRC after local resection, especially regarding favorable outcomes in patients with low risk of LNM.

Enhanced Clinical Utility of Molecular Budding Signature as a Recurrence Risk Determinant in Stage II and III Colon Cancer Patients.

BACKGROUND: A molecular budding signature (MBS), which consists of seven tumor budding-related genes, was recently presented as a prominent prognostic indicator in colon cancer (CC) using microarray data acquired from frozen specimens. This study aimed to confirm the predictive power of MBS for recurrence risk based on formalin-fixed, paraffin-embedded (FFPE) materials. METHODS: This research utilized the same microarray data from a prior multicenter study using FFPE whole tissue sections, which retrospectively reviewed 232 stage II CC patients without adjuvant chemotherapy and 302 stage III CC patients with adjuvant chemotherapy. All patients underwent upfront curative surgery without neoadjuvant therapy between 2009 and 2012. An MBS score was calculated using the mean of log2 [each signal] of seven genes (MSLN, SLC4A11, WNT11, SCEL, RUNX2, MGAT3, and FOXC1) as described before. RESULTS: The MBS-low group exhibited a better relapse-free survival (RFS) than the MBS-high group in stage II (P = 0.0077) and in stage III CC patients (P = 0.0003). Multivariate analyses revealed that the MBS score was an independent prognostic factor in both stage II (P = 0.0257) and stage III patients (P = 0.0022). Especially among T4, N2, or both (high-risk) stage III patients, the MBS-low group demonstrated markedly better RFS compared with the MBS-high group (P = 0.0013). CONCLUSIONS: This study confirmed the predictive power of the MBS for recurrence risk by employing FFPE materials in stage II/III CC patients.

Nomogram as a novel predictive tool for lymph node metastasis in T1 colorectal cancer treated with endoscopic resection: a nationwide, multicenter study.

BACKGROUND AND AIMS: Since 2009, the Japanese Society for Cancer of the Colon and Rectum guidelines have recommended that tumor budding and submucosal invasion depth, in addition to lymphovascular invasion and tumor grade, be included as risk factors for lymph node metastasis (LNM) in patients with T1 colorectal cancer (CRC). In this study, a novel nomogram was developed and validated by usirge-scale, real-world data, including the Japanese Society for Cancer of the Colon and Rectum risk factors, to accurately evaluate the risk of LNM in T1 CRC. METHODS: Data from 4673 patients with T1 CRC treated at 27 high-volume institutions between 2009 and 2016 were analyzed for LNM risk. To prepare a nonrandom split sample, the total cohort was divided into development and validation cohorts. Pathologic findings were extracted from the medical records of each participating institution. The discrimination ability was measured by using the concordance index, and the variability in each prediction was evaluated by using calibration curves. RESULTS: Six independent risk factors for LNM, including submucosal invasion depth and tumor budding, were identified in the development cohort and entered into a nomogram. The concordance index was .784 for the clinical calculator in the development cohort and .790 in the validation cohort. The calibration curve approached the 45-degree diagonal in the validation cohort. CONCLUSIONS: This is the first nomogram to include submucosal invasion depth and tumor budding for use in routine pathologic diagnosis based on data from a nationwide multi-institutional study. This nomogram, developed with real-world data, should improve decision-making for an appropriate treatment strategy for T1 CRC.

Prognostic value of desmoplastic reaction characterisation in stage II colon cancer: prospective validation in a Phase 3 study (SACURA Trial).

BACKGROUND: The characterisation of desmoplastic reaction (DR) has emerged as a new, independent prognostic determinant in colorectal cancer. Herein, we report the validation of its prognostic value in a randomised controlled study (SACURA trial). METHODS: The study included 991 stage II colon cancer patients. DR was classified by the central review as Mature, Intermediate or Immature based on the presence of hyalinised collagen bundles and myxoid stroma at the desmoplastic front. All clinical and pathological data, including DR characterisations, were prospectively recorded and analysed 5 years after the completion of the registration. RESULTS: The five-year relapse-free survival (RFS) rate was the highest in the Mature group (N = 638), followed by the Intermediate (N = 294) and Immature groups (N = 59). Multivariate analysis revealed that DR classification was an independent prognostic factor, and based on Harrell's C-index, the Cox model for predicting RFS was significantly improved by including DR. In the conditional inference tree analysis, DR categorisation was the first split factor for predicting RFS, followed by T-stage, microsatellite instability status and budding. CONCLUSIONS: Histological categorisation of DR provides important prognostic information that could contribute to the efficient selection of stage II colon cancer patients who would benefit from postoperative adjuvant therapy.

Evaluation of a 55-gene classifier as a prognostic biomarker for adjuvant chemotherapy in stage III colon cancer patients.

BACKGROUND: Adjuvant chemotherapy reduces the risk of recurrence of stage III colon cancer (CC). However, more effective prognostic and predictive biomarkers are needed for better treatment stratification of affected patients. Here, we constructed a 55-gene classifier (55GC) and investigated its utility for classifying patients with stage III CC. METHODS: We retrospectively identified patients aged 20-79 years, with stage III CC, who received adjuvant chemotherapy with or without oxaliplatin, between the years 2009 and 2012. RESULTS: Among 938 eligible patients, 203 and 201 patients who received adjuvant chemotherapy with and without oxaliplatin, respectively, were selected by propensity score matching. Of these, 95 patients from each group were analyzed, and their 5-year relapse-free survival (RFS) rates with and without oxaliplatin were 73.7 and 77.1%, respectively. The hazard ratios for 5-year RFS following adjuvant chemotherapy (fluoropyrimidine), with and without oxaliplatin, were 1.241 (95% CI, 0.465-3.308; P = 0.67) and 0.791 (95% CI, 0.329-1.901; P = 0.60), respectively. Stratification using the 55GC revealed that 52 (27.3%), 78 (41.1%), and 60 (31.6%) patients had microsatellite instability (MSI)-like, chromosomal instability (CIN)-like, and stromal subtypes, respectively. The 5-year RFS rates were 84.3 and 72.0% in patients treated with and without oxaliplatin, respectively, for the MSI-like subtype (HR, 0.495; 95% CI, 0.145-1.692; P = 0.25). No differences in RFS rates were noted in the CIN-like or stromal subtypes. Stratification by cancer sidedness for each subtype showed improved RFS only in patients with left-sided primary cancer treated with oxaliplatin for the MSI-like subtype (P = 0.007). The 5-year RFS rates of the MSI-like subtype in left-sided cancer patients were 100 and 53.9% with and without oxaliplatin, respectively. CONCLUSIONS: Subclassification using 55GC and tumor sidedness revealed increased RFS in patients within the MSI-like subtype with stage III left-sided CC treated with fluoropyrimidine and oxaliplatin compared to those treated without oxaliplatin. However, the predictive power of 55GC subtyping alone did not reach statistical significance in this cohort, warranting larger prospective studies. TRIAL REGISTRATION: The study protocol was registered in the University Hospital Medical Education Network (UMIN) clinical trial registry (UMIN study ID: 000023879 ).

Histopathological atlas of desmoplastic reaction characterization in colorectal cancer.

Emergent scientific evidence indicates the central role of cancer-associated fibroblasts in determining whether the microenvironment of cancer works as friend or foe of the host; however, there is no unified histological evaluation framework of fibrotic stroma in colorectal cancers. Myxoid stroma and keloid-like collagen are site-specific histopathological features generated by cancer-associated fibroblasts, which appear exclusively in the tumor front during desmoplastic reaction. On the basis of these two stromal components, desmoplastic reaction is categorized into three patterns-immature, intermediate and mature-using hematoxylin and eosin staining. In January 2020, a prospective randomized clinical trial, JCOG1805, to elucidate the value of adjuvant chemotherapy in stage II colorectal cancer patients with pathological risk factors of recurrence was launched in Japan, in which intermediate/immature desmoplastic reaction is one of the four risk factors selected as inclusion criteria. This paper covers the diagnostic criteria for the desmoplastic reaction classification being used in the JCOG1805 study.

[Points for Evaluating Japanese Subgroup in the Multi-Regional Clinical Trial].

While the multi-regional clinical trial may accelerate the worldwide development and contribute to avoiding drug lag, differences in the results of efficacy and safety/tolerability among the regions are observed occasionally. These differences complicate the evaluation of clinical value of the study drug. To be able to evaluate consistency of treatment effects across regions, possible intrinsic and extrinsic ethnic factors should be considered at the planning of the study. Although some differences of therapeutic effects across the regions are found, these differences can be attributed to differences in intrinsic or extrinsic factors. Consistency of the efficacy and safety of the anti-cancer drug across the regional subgroups and entire population should be comprehensively examined in the multi-regional clinical trial.

A Validation Study for Recurrence Risk Stratification of Stage II Colon Cancer Using the 55-Gene Classifier.

INTRODUCTION: DNA microarrays, such as the consensus molecular subtype (CMS) classification using >600 genes, are used to predict cancer patient prognosis. We recently constructed a simple 55-gene classifier (55GC) system to risk stratify colon cancer (CC). OBJECTIVE: Here, we validate the 55GC specifically for stage II CC and compare it with CMS categories. METHODS: Tissue sections from 232 stage II CC patients who underwent curative surgery without adjuvant chemotherapy between 2009 and 2012 were subjected to DNA microarray analysis. RESULTS: Based on the 55GC, patients were classified into microsatellite instability-like (27%), chromosomal instability-like (41%), and stromal (32%) subtypes with 5-year relapse-free survival (RFS) rates of 88.5, 83.3, and 71.2%, respectively (stromal vs. others: p = 0.0049). Multivariate analysis by Cox's proportional hazard model revealed that the stromal subtype, pT4, and the number of lymph nodes examined (<12) were independent poor prognostic factors. The overall concordance rate between 55GC and CMS was 72%, and 5-year RFS rates of patients with CMS1, CMS2, CMS3, and CMS4 cancers were 100, 85.5, 92.3, and 73.0%, respectively (p = 0.0113). CONCLUSIONS: We conclude that the 55GC is a useful and reproducible grading system for stage II CC recurrence risk stratification.

Challenges of improving treatment outcomes for colorectal and anal cancers in Japan: the Colorectal Cancer Study Group (CCSG) of the Japan Clinical Oncology Group (JCOG).

Colorectal cancer is a major public health concern in Japan. While early-stage colorectal adenocarcinoma treatment entails radical resection of the primary tumor, the importance of perioperative treatment is growing as physicians seek to further improve treatment outcomes. For anal squamous cell carcinoma, definitive chemoradiotherapy is superior to radical surgery in terms of improved patient quality of life. The Colorectal Cancer Study Group of the Japanese Clinical Oncology Group was established in 2001 and has worked to provide answers to common clinical questions and improve treatment outcomes for colorectal and anal cancers through 15 large-scale prospective clinical trials. Here, we discuss the current state of perioperative treatment for early-stage colon, rectal and anal cancers in Japan and approaches taken by the Colorectal Cancer Study Group/the Japanese Clinical Oncology Group to improve treatment outcomes for these cancers.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2019 for the treatment of colorectal cancer.

The number of deaths from colorectal cancer in Japan continues to increase. Colorectal cancer deaths exceeded 50,000 in 2016. In the 2019 edition, revision of all aspects of treatments was performed, with corrections and additions made based on knowledge acquired since the 2016 version (drug therapy) and the 2014 version (other treatments). The Japanese Society for Cancer of the Colon and Rectum guidelines 2019 for the treatment of colorectal cancer (JSCCR guidelines 2019) have been prepared to show standard treatment strategies for colorectal cancer, to eliminate disparities among institutions in terms of treatment, to eliminate unnecessary treatment and insufficient treatment and to deepen mutual understanding between healthcare professionals and patients by making these guidelines available to the general public. These guidelines have been prepared by consensuses reached by the JSCCR Guideline Committee, based on a careful review of the evidence retrieved by literature searches and in view of the medical health insurance system and actual clinical practice settings in Japan. Therefore, these guidelines can be used as a tool for treating colorectal cancer in actual clinical practice settings. More specifically, they can be used as a guide to obtaining informed consent from patients and choosing the method of treatment for each patient. Controversial issues were selected as clinical questions, and recommendations were made. Each recommendation is accompanied by a classification of the evidence and a classification of recommendation categories based on the consensus reached by the Guideline Committee members. Here, we present the English version of the JSCCR guidelines 2019.

Phase III randomised trial comparing 6 vs. 12-month of capecitabine as adjuvant chemotherapy for patients with stage III colon cancer: final results of the JFMC37-0801 study.

BACKGROUND: Up to 6-months oxaliplatin-containing regimen is now widely accepted as a standard adjuvant chemotherapy for stage III colorectal cancer (CRC). However, oral fluoropyrimidine monotherapy is used for some part of patients, especially in Asian countries including Japan, and its optimal duration is yet to be fully investigated. METHODS: A total of 1306 patients with curatively-resected stage III CRC were randomly assigned to receive capecitabine (2500 mg/m2/day) for 14 out of 21 days for 6 (n = 654) or 12 (n = 650) months. The primary endpoint was disease-free survival (DFS), and the secondary endpoints were relapse-free survival (RFS), overall survival (OS), and adverse events. RESULTS: The 3- and 5-year DFS were 70.0% and 65.3% in the 6M group and 75.3% and 68.7% in the 12M group, respectively (p = 0.0549, HR = 0.858, 90% CI: 0.732-1.004). The 5-year RFS was 69.3% and 74.1% in the 6M and 12M groups, respectively (p = 0.0143, HR = 0.796, 90% CI: 0.670-0.945). The 5-year OS was 83.2% and 87.6%, respectively (p = 0.0124, HR = 0.727, 90% CI: 0.575-0.919). The incidence of overall grade 3-4 adverse events was almost comparable in both groups. CONCLUSIONS: Although 12-month adjuvant capecitabine did not demonstrate superior DFS to that of 6-month, the observed better RFS and OS in the 12-month treatment period could be of value in selected cases.

mFOLFOX6 plus bevacizumab to treat liver-only metastases of colorectal cancer that are unsuitable for upfront resection (TRICC0808): a multicenter phase II trial comprising the final analysis for survival.

BACKGROUND: The TRICC0808 trial is a phase II multi-institutional trial that investigated the efficacy of preoperative mFOLFOX6 + bevacizumab (BV) therapy for liver-only metastasis that is unsuitable for upfront resection. The R0 resection rate in the efficacy analysis has been reported to be 44.4%, and the final analysis for survival was conducted (data fixation on February 16, 2015). METHODS: Six cycles of mFOLFOX6 + BV therapy were applied to patients with liver-only metastases, which were > 5 cm in diameter or more than four tumors (H2 and H3), and hepatectomy was performed if possible. Primary and secondary endpoints were the R0 hepatectomy rate and overall survival (OS), respectively. RESULTS: Of 46 patients registered, OS was analyzed for 45 patients in whom the 3-year OS rate from the starting date of chemotherapy was 44.0% with a 33.6-month median survival time (MST). The 3-year OS rate of 31 patients with hepatectomy, including resection after an additional chemotherapy, was 61.3% with a 43.1-month MST, which was significantly better than 0% of the 3-year OS rate with a 21.0-month MST of 14 patients without hepatectomy (p value < 0.0001). In 24 patients who underwent hepatectomy after six cycles of protocol chemotherapy, the 3-year relapse-free survival rate was 8.3%, with a 36.8-month MST. CONCLUSIONS: This final analysis of the TRICC0808 trial revealed a better long-term survival in patients with hepatectomy after mFOLFOX6 + BV therapy, although most examined patients eventually developed recurrence. Thus, hepatectomy after chemotherapy might improve the survival in patients with advanced liver metastases, although cure remains difficult.

Current status of site-specific cancer registry system for the clinical researches: aiming for future contribution by the assessment of present medical care.

BACKGROUND: The current status of site-specific cancer registry has not been elucidated, but sufficient system is found in some societies. The purpose of this study was to clear the present condition of site-specific cancer registries in Japan and to suggest for the improvement. METHODS: The questionnaire was conducted by the study group of the Ministry of Health, Labor, and Welfare. It consisted of 38 questions, conflicts of interest, clinical research method, informed consent and funding for registry. We distributed this questionnaire to 28 academic societies, which had published the clinical practice guideline(s) assessed under Medical Information Network Distribution Service (MINDS). RESULTS: The concept of the importance in assessment for medical quality by the data of the site-specific cancer registry was in good consensus. But the number of the society with the mature registry was limited. The whole-year registry with the scientific researches in the National Clinical Database (NCD) and in the Translational Research Informatics Center (TRI) might seem to be in success, because assured enhancement may be estimated. Now, academic societies have the structural factors, i.e., the financial limitation in the registry maintenance and the data analysis, and in the difficulty of employment of the researchers with skill and talent. CONCLUSIONS: To manage the site-specific cancer registry effectively, the scientific registry system will be essentially important. Each academic society had much experienced highly qualified clinical researches in past. Accordingly, the scientific suggestion and co-operation should be of great importance for the improvement.

Current clinical practice of adjuvant chemotherapy for patients with 'high-risk' Stage II colorectal cancer in Japan: a questionnaire survey in the JCOG Study Group.

While the major Western guidelines recommend adjuvant chemotherapy for patients having Stage II colorectal cancer (CRC) with 'high-risk' features, e.g., pT4 and lymphovascular involvement, the survival benefit has not been confirmed. To understand the actual clinical practice for this patient subgroup in Japan, we performed a questionnaire survey of specialist institutions regarding two topics: institutional policy of adjuvant chemotherapy, and the percentage of patients receiving adjuvant chemotherapy among 'high-risk' Stage II CRC patients. Among the 55 responders out of 60 institutions (response rate, 91.7%), 80.0% did not routinely administer adjuvant chemotherapy for 'high-risk' Stage II patients. The median percentage of 'high-risk' Stage II patients receiving adjuvant chemotherapy was 25%, with ≤30% in 35 institutions, and >60% in 12. In summary, performance of adjuvant chemotherapy for patients with 'high-risk' Stage II CRC varied substantially, even among these specialist institutions, and a majority of patients received no adjuvant chemotherapy.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2016 for the treatment of colorectal cancer.

Japanese mortality due to colorectal cancer is on the rise, surpassing 49,000 in 2015. Many new treatment methods have been developed during recent decades. The Japanese Society for Cancer of the Colon and Rectum Guidelines 2016 for the treatment of colorectal cancer (JSCCR Guidelines 2016) were prepared to show standard treatment strategies for colorectal cancer, to eliminate disparities among institutions in terms of treatment, to eliminate unnecessary treatment and insufficient treatment, and to deepen mutual understanding between health-care professionals and patients by making these Guidelines available to the general public. These Guidelines were prepared by consensus reached by the JSCCR Guideline Committee, based on a careful review of the evidence retrieved by literature searches, and in view of the medical health insurance system and actual clinical practice settings in Japan. Therefore, these Guidelines can be used as a tool for treating colorectal cancer in actual clinical practice settings. More specifically, they can be used as a guide to obtaining informed consent from patients and choosing the method of treatment for each patient. As a result of the discussions held by the Guideline Committee, controversial issues were selected as Clinical Questions, and recommendations were made. Each recommendation is accompanied by a classification of the evidence and a classification of recommendation categories based on the consensus reached by the Guideline Committee members. Here we present the English version of the JSCCR Guidelines 2016.

[Two Cases of Rectal Cancer with Pelvic Local Recurrence Complicated with Sepsis after Rectal Cancer Surgery Successfully Treated with Radiation Therapy].

Treatment of rectal cancer with postoperative pelvic recurrence may complicate infection and may be difficult to treat. We experienced 2 cases complicated with sepsis due to infection in the pelvic local recurrence in which radiation therapy was performed and they were shifted to outpatient molecular-targeted drug therapy. Case 1 involved a 58-year-old woman. In December 2011, colostomy and chemotherapy were performed for locally advanced rectal cancer. In June 2012, we performed low anterior resection. In January 2014, chemotherapy was started for pelvic recurrence. She discontinued treatment for 4 months due to personal circumstances. Recurrence was worsened, and infection caused sepsis and she was admitted to the hospital in February 2017. Infection was not improved with antibiotic drugs, and radiation therapy(60 Gy/30 times)was performed. Infection was improved, and panitumumab monotherapy was started and she was discharged. Case 2 involved a 61-year-old man. In February 2014, a lower anterior resection for rectal cancer was performed. In September 2015, chemotherapy was started for pelvic recurrence. In November 2016, chemotherapy was discontinued due to esophageal variceal rupture. Recurrence was worsened, and infection caused sepsis and he was admitted to the hospital in May 2017. Radiation therapy(50 Gy/20 times)was performed after colostomy. Infection was improved, and cetuximab monotherapy was started and he was discharged.

Morphologic change of the psoas muscle as a surrogate marker of sarcopenia and predictor of complications after colorectal cancer surgery.

PURPOSE: Sarcopenia is reported to be associated with complications after surgery. However, there is no established optimal parameter to determine sarcopenia affecting surgical outcome. This study investigated whether morphologic change of the psoas muscle (MPM) reflects sarcopenia and could be a predictor of complications after colorectal cancer surgery. METHODS: Colorectal cancer patients who underwent primary tumor resection with anastomosis between 2015 and 2016 were analyzed. MPM score was evaluated as the ratio of the short-to-long axis of the psoas muscle in CT images at the L3 vertebrae and classified into five MPM grades. Then, the impact of MPM grade on development of postoperative complications was investigated. RESULTS: A total of 133 patients were studied. MPM score was significantly correlated to the sectional areas of the psoas muscle at the L3 vertebrae which was evaluated by manual tracing. 21.1% of the subjects were classified into severe MPM (defined as MPM grade 3-4). Overall and infectious complications were noted in 37 (27.8%) and 16 (12.0%) patients. Severe MPM (odds ratio [OR] 2.71, 95% confidence interval [CI] 1.09-6.73), longer operative time (OR 1.01, 95%CI 1.001-1.01), and open surgery (OR 2.73, 95%CI 1.17-6.35) were identified as independent risk factors of overall complications. Severe MPM (OR 4.26,95%CI 1.38-13.10) and open surgery (OR 3.42, 95%CI 1.11-10.48) were identified as independent factors associated with infectious complications. CONCLUSIONS: MPM grade may be used as a simple and convenient marker of sarcopenia and to identify patients at increased risk of complications after colorectal cancer surgery.