Assessment of Elastic Laminal Invasion Contributes to an Objective pT3 Subclassification in Colon Cancer.

The extent of tumor spread influences on the clinical outcome, and which determine T stage of colorectal cancer. However, pathologic discrimination between pT3 and pT4a in the eighth edition of the American Joint Committee on Cancer (AJCC)-TNM stage is subjective, and more objective discrimination method for deeply invasive advanced colon cancer is mandatory for standardized patient management. Peritoneal elastic laminal invasion (ELI) detected using elastic staining may increase the objective discrimination of deeply invasive advanced colon cancer. In this study, we constructed ELI study group to investigate feasibility, objectivity, and prognostic utility of ELI. Furthermore, pT classification using ELI was investigated based on these data. At first, concordance study investigated objectivity using 60 pT3 and pT4a colon cancers. Simultaneously, a multi-institutional retrospective study was performed to assess ELI's prognostic utility in 1202 colon cancer cases from 6 institutions. In the concordance study, objectivity, represented by κ, was higher in the ELI assessment than in pT classification. In the multi-institutional retrospective study, elastic staining revealed that ELI was a strong prognostic factor. The clinical outcome of pT3 cases with ELI was significantly and consistently worse than that of those without ELI. pT classification into pT3 without ELI, pT3 with ELI, and pT4a was an independent prognostic factor. In this study, we revealed that ELI is an objective method for discriminating deeply invasive advanced colon cancer. Based on its feasibility, objectivity, and prognostic utility, ELI can subdivide pT3 lesions into pT3a (without ELI) and pT3b (with ELI).

Positive Circumferential Resection Margin in Rectal Cancer Is a Robust Predictor of Poor Long-term Prognosis With Clinicopathological Bias Between Groups Compensated by Propensity-score Matching Analysis.

BACKGROUND/AIM: Circumferential resection margin (CRM) is the most reliable predictor of local and distant recurrence in locally-advanced rectal cancer (LARC). The present study was conducted to compare the long-term outcomes between CRM (+) and (-) groups using propensity-score (PS) matching analysis to compensate for bias between groups. PATIENTS AND METHODS: Of 563 consecutive patients with Stage II/III rectal cancer who were treated surgically with curative-intent at Juntendo University Hospital between Jan 1989 and Mar 2018, 412 patients were enrolled retrospectively in the study. The patients were divided into a CRM (+) group (n=21; 5.1%) and a CRM (-) group (n=391; 94.9%). RESULTS: In the entire cohort, recurrence-free survival (RFS), local recurrence-free survival (LRFS), non-local recurrence-free survival (NLRFS), and cancer-specific survival (CSS) were significantly worse among patients in the CRM (+) group compared with those in the CRM (-) group. Univariate analysis demonstrated patients in the CRM (+) group had significantly larger primary tumors (p=0.02), more frequently had open surgery (p=0.009), had an abdominoperineal resection (APR) procedure (p=0.01) and a T4 primary tumor (p<0.0001). After PS matching analysis, in the propensity-matched cohort, RFS, LRFS, NLRFS and CSS were significantly worse among patients in the CRM (+) group compared with those in the CRM (-) group. CONCLUSION: PS matching analysis demonstrated that RFS, LRFS, NLRFS, and CSS were significantly worse among patients in the CRM (+) group compared with those in the CRM (-) group. The present results indicate that CRM (+) is a robust predictor of long-term outcome of LARC, independent of tumor size.

Local recurrence of submucosal invasive colorectal cancer after endoscopic submucosal dissection revealed by copy number variation.

We report a case in which analysis of copy number variation revealed local recurrence of submucosal invasive colorectal cancer after curative endoscopic submucosal dissection (ESD). An 86-year-old man with a history of abdominoperineal resection of the rectum for rectal cancer underwent resection with ESD for early-stage sigmoid cancer 5 cm away from the stoma opening. At the same time, ileocecal resection was performed for advanced cecal cancer. Twelve months after ESD, advanced cancer occurred in the area of the ESD lesion. It was unclear if the cancer was a local recurrence after ESD, implantation of cecal cancer, or a new lesion. Copy number variation analysis performed for the three lesions revealed that the new lesion originated from residual tumor cells from ESD and was unlikely to be cecal cancer.

Examination of colorectal cancer cases with metal allergy.

PURPOSE: To report our initiatives and treatment results for patients with colorectal cancer with metal allergy. METHODS: A total of 27 patients (2.6%) with a history of metal contact dermatitis were identified among 1027 patients who underwent curative resection of colorectal cancer from 2014 to 2020. The results of the patch test, perioperative results, and postoperative colonoscopy findings were also investigated. RESULTS: The patch test for metal allergens and staples was performed in 21 patients (77.8%), and 13 of them (61.9%) tested positive for at least one metal allergen. Ni (38.1%), Co (28.6%), and Pd (19.0%) showed higher positive rates than other metals, and 1 patient (4.8%) tested positive for staples. Stapled anastomosis/suturing was performed as planned in 15 of 27 patients. In 10 patients, the anastomosis method was changed from stapled to hand-sewn according to the no-patch test results (60%), positivity for multiple metals (20%), positivity for staples (10%), and surgeon's judgment (10%). No complications and abnormal colonoscopy findings were found to be associated with stapled anastomosis/suturing. CONCLUSION: The patch test is useful for selecting an optimal anastomosis method for patients with suspected metal allergy.

[A Case of Recurrence in the Abdominal Wall and Perineal Region of Rectal Cancer Successfully Treated with Minimally Invasive Surgery and Radiation Therapy].

Local recurrence after rectal cancer surgery is often difficult to treat because there are few effective treatments. In this study, we report a case of parastomal and perineal recurrence after Miles' surgery in an elderly patient who had a favorable outcome after laparoscopic surgery and radiation therapy. Our results suggest that a combination of minimally invasive treatment may be effective in elderly patients and after polysurgery.

Analysis of appendectomy samples identified dysbiosis in acute appendicitis.

Appendicitis is the most common cause of sudden-onset abdominal pain requiring surgery. Culture-independent techniques have revealed that the complex intestinal bacterial ecology is associated with various diseases. To evaluate differences in patient characteristics and gut microbiota distribution in patients with appendicitis, we enrolled 12 patients who underwent appendectomy for appendicitis (appendicitis group) and 13 patients who underwent ileocecal resection or right hemicolectomy for colon cancer (control group). Microbiota were analyzed using next-generation sequencing of surgical specimens from appendix swab samples collected postoperatively. Overall differences in the structure of the gut microbiota were evaluated using the α- and ß-diversity indices, which were calculated using the weighted or unweighted UniFrac distance. Changes in the gut microbial distribution were taxonomically evaluated at the phylum and genus levels. The α-diversity of observed species was significantly different between patients with and without inflammation of the appendix. The appendiceal microbiome of patients with appendicitis exhibited the highest unweighted UniFrac distances. There were no significant differences at the phylum level. Ruminococcus (p=0.02) and f_erysipelotrichaceae_g_clostridium (p=0.005) were increased in the control group compared with the appendicitis group. This pilot study provides the first report of the correlation of the gut microbiota with the pathogenesis of appendicitis evaluated using mucus-origin sampling.

Significance of postoperative adjuvant chemotherapy with an oxaliplatin-based regimen after simultaneous curative resection for colorectal cancer and synchronous colorectal liver metastasis: a propensity score matching analysis.

BACKGROUND: Expansion of the indication for liver resection and new regimens for systemic chemotherapy have improved postoperative outcomes for synchronous colorectal liver metastases (CRLM). However, such cases can still have a high recurrence rate, even after curative resection. Therefore, there is a need for postoperative adjuvant chemotherapy (POAC) after liver resection in patients with CRLM. There are few studies of the efficacy of POAC with an oxaliplatin-based regimen after simultaneous resection for colorectal cancer and CRLM with curative intent. The goal of the study was to compare POAC with oxaliplatin-based and fluoropyrimidine regimens using propensity score (PS) matching analysis. METHODS: The subjects were 94 patients who received POAC after simultaneous resection for colorectal cancer and synchronous CRLM, and were enrolled retrospectively. The patients were placed in a L-OHP (+) group (POAC with an oxaliplatin-based regimen, n = 47) and a L-OHP (-) group (POAC with a fluoropyrimidine regimen, n = 47). Recurrence-free (RFS), cancer-specific (CSS), unresectable recurrence-free (URRFS), remnant liver recurrence-free (RLRFS), and extrahepatic recurrence-free (EHRFS) survival were analyzed. RESULTS: Before PS matching, the L-OHP (+) and (-) groups had no significant differences in RFS, CSS, URRFS, RLRFS, and EHRFS. Univariate analysis indicated significant differences in age, preoperative serum CEA (≤ 30.0 ng/mL/ > 30.0 ng/mL), differentiation of primary tumor (differentiated/undifferentiated), T classification (T1-3/T4), number of hepatic lesions and maximum diameter of the hepatic lesion between the L-OHP (+) and (-) groups. After PS matching using these confounders, RFS was significantly better among patients in the L-OHP (+) group compared with the L-OHP (-) group (HR 0.40, 95% CI 0.17-0.96, p = 0.04). In addition, there was a trend towards better RLRFS among patients in the L-OHP (+) group compared with the L-OHP (-) group (HR 0.42, 95% CI 0.17-1.02, p = 0.055). However, there were no significant differences in CSS, URRFS and EHRFS between the L-OHP (+) and (-) groups. CONCLUSIONS: PS matching analysis demonstrated the efficacy of POAC with an oxaliplatin-based regimen in RFS and RLRFS.

[A Case of Good Quality of Life(QOL)and Favorable Response to Transarterial Chemoembolization(TACE)against Synchronous Multiple Liver Metastases].

We report a case of good quality of life(QOL)and favorable response to transarterial chemoembolization(TACE)against synchronous multiple liver metastases. An 85-year-old man was admitted to our hospital because of melena. Colonoscopy showed multiple type 2 tumors in the sigmoid colon and upper rectum. CT and EOB-MRI examinations revealed that there were multiple liver metastases. Because of his age and surgical stress, he underwent a laparoscopic Hartmann's procedure. After the resection of the primary tumor, he received tegafur/uracil for his liver metastases. However, he discontinued receiving the drugs 2 weeks later because of the development of adverse events. Instead of systemic chemotherapy, he chose to undergo TACE. He underwent TACE with irinotecan and HepaSphereTM(BioSphere Medical)8 times for his multiple liver metastases. Consequently, all multiple liver metastases disappeared. Therefore, TACE may be useful for patients who are not suitable for systemic chemotherapy.

[A Case of Systemic Chemotherapy Combined with Molecular Drug Treatment Following Biliary Stent Implantation for Obstructive Jaundice Due to Metastases of Liver Gland Lymph Node after Colorectal Cancer Surgery].

We report a case of systemic chemotherapy after biliary stent placement for obstructive jaundice due to hepatic portal lymph node metastasis after colorectal cancer surgery. The patient was a 40s woman. Laparoscopic anterior resection for rectosigmoidRS cancer was performed. The pathological diagnosis was T3N0M0PUL0R0, pStage Ⅱ according to the 8th edition of colorectal cancer handling regulations. Because multiple liver metastases were observed 8 months after the surgery, partial resection of the posterior region of the liver was performed. Multiple lung metastases were observed 1 year after hepatectomy, but she wantedto undergo follow-up observation. Jaundice was observed 1 year after the diagnosis of lung metastasis, and obstructive jaundice due to hepatic portal lymph node metastasis was diagnosed. Endoscopic retrograde biliary drainage(ERBD)was performed, and a bile duct stent was placed. After improving jaundice, 12 courses of mFOLFOX6 plus cetuximab therapy were performed. Currently, because of the exacerbation of lung metastasis, FOLFIRI plus bevacizumab therapy is being administered. Systemic chemotherapy containing a molecular-targeted drug is being administered in our case, but complications relatedto the biliary stent have not been observed. There are few reports on similar cases, andfollow - up observation with careful attention to long-term safety is necessary.

Recommendation of long-term and systemic management according to the risk factors in rectal NETs patients.

Rectal neuroendocrine tumors (NETs) are often found as small lesions, which can be treated by endoscopic resection. However, high risk cases with lymph node (LN) metastasis are indication of radical surgery. Furthermore, rectal NETs are often associated with late recurrences and/or multiple cancer development. Therefore, proper surgical indication and patients' management are required. We investigated the clinicopathological features of 79 rectal NET cases in order to elucidate risk factors for synchronous LN metastasis, recurrence, and multiple cancers. Recently, we reported that in pancreatic NET patients, a loss of heterozygosity (LOH) in PHLDA3 was associated with poorer prognosis, and that LOH of both PHLDA3 and MEN1 was frequently observed. Therefore, PHLDA3 and MEN1 LOH were also assessed in rectal NET patients for their association with clinicopathological features. Of the 79 patients, LN metastases were found in 12.7%, recurrences in 3.8%, and multiple cancers in 30.4% of the subjects. PHLDA3 and MEN1 LOH were found in 60.0% and 66.7% of the subjects, respectively. Lymphatic invasion and WHO classification 2010 were found to be independent risks for LN metastasis. There were three cases of recurrence, all of which occurred more than 3 years after resection and two of which exhibited LN metastasis. Older age and LOH in PHLDA3 were associated with the presence of multiple cancers. Long-term and systemic management of patients with rectal NETs is therefore recommended in accordance with these risk factors.

[A Study of Treatment for Pathological T1(SM)Colorectal Cancer Patients after Endoscopic Resection at Our Department].

Approximately 10% of pathological T1(SM)colorectal cancer patients develop lymph node metastases. Therefore additional colectomy with lymph node dissection is recommended when it applies to the specific criteria in the current JSCCR guidelines. However, additional colectomy would not be done in some cases, because surgery is too invasive for some patients. Endoscopic treatment(ESD or EMR)for T1(SM)cancer was performed in 324 cases between 2008 and 2016. Of those, 231 cases had satisfied the criteria for additional colectomy. Among them, 74 cases(32.0%)did not undergo, and additional colectomy(+)groupwas 153 cases(66.2%). Between the 2 groups, no difference in prognosis could be found. We considered there was no difference, because the prognosis of SM cancer is relatively good. In consideration of patient background, the treatment policy has to be chosen according to feasibility.

[A Case of Pelvic Metastasis of Rectal Cancer That Developed Ten Years after Curative Resection].

We report a case of pelvic metastasis of rectal cancer that developed 10 years after curative resection. An 81-year-old woman underwent intersphincteric resection for lower rectal cancer 10 years previously. The tumor was pathologically diagnosed as T2N0M0, Stage Ⅰ. Nine years after the curative resection, serum carcinoembryonic antigen(CEA)levels were slightly elevated, but no recurrence was found on computed tomography(CT). Eleven months after CT, serum CEA levels elevated to 15.9 ng/mL. Pelvic metastasis in the piriformis muscle was detected on positron emission tomography(PET)-CT. Following CT-guided biopsy, she was pathologically diagnosed with metastatic rectal cancer. Radiotherapy (60 Gy/30 Fractions) was administered. Ten months after radiotherapy, PET-CT revealed no relapse in the pelvis with lung metastases.

Postoperative portal vein thrombosis and gastric hemorrhage associated with late-onset hemorrhage from the common hepatic artery after pancreaticoduodenectomy.

Portal vein thrombosis (PVT) is a rare but serious postoperative complication of pancreaticoduodenectomy (PD). We reported a case of late-onset postoperative PVT with hemorrhage from the common hepatic artery (CHA) in a 73-year-old man who underwent pylorus-preserving pancreaticoduodenectomy (PPPD) for duodenum papilla cancer, followed by reconstruction using the modified Child's technique. The pancreaticojejunostomy was achieved by end-to-side, 2-layer invagination anastomosis without pancreatic duct stenting. Drain removal and hospital discharge were scheduled on postoperative day (POD) 18, but blood-stained fluid in the drain and sudden hematemesis were noted. Emergency surgery was performed because PVT and imaging findings were suggestive of necrosis of the lifted jejunum. Although no jejunal necrosis was identified during surgery, bleeding from the side of the CHA was detected and the bleeding point was suture-closed to achieve hemostasis. We suspected late-onset postoperative arterial hemorrhage and subsequent hematoma formation, which caused portal vein compression and PVT formation. We chose a conservative treatment strategy for PVT, taking into account the operation time, intraoperative vital signs and blood flow in the portal vein. Despite the complicated postoperative course, he was discharged home in a fully ambulatory state on POD 167.

Laparoscopic resection of an intra-abdominal esophageal duplication cyst: a case report and literature review.

Duplication of the alimentary tract is a rare congenital malformation that occurs most often in the abdominal region, whereas esophageal duplication cyst develops typically in the thoracic region but occasionally in the neck and abdominal regions. Esophageal duplication cyst is usually diagnosed in early childhood because of symptoms related to bleeding, infection, and displacement of tissue surrounding the lesion. We recently encountered a rare adult case of esophageal duplication cyst in the abdominal esophagus. A 50-year-old man underwent gastroscopy, endoscopic ultrasonography, computed tomography, and magnetic resonance imaging to investigate epigastric pain and dysphagia that started 3 months earlier. Imaging findings suggested esophageal duplication cyst, and the patient underwent laparoscopic resection followed by intraoperative esophagoscopy to reconstruct the esophagus safely and effectively. Histopathological examination of the resected specimen revealed two layers of smooth muscle in the cystic wall, confirming the diagnosis of esophageal duplication cyst.