Clinical T2N0 Rectal Cancer Treated with Neoadjuvant Chemoradiotherapy plus Local Excision.

INTRODUCTION: Total mesorectal excision is the standard treatment for clinical T2 (cT2) rectal cancer; however, this procedure can result in postoperative dysfunction, decreased quality of life, and stoma creation in some patients. We investigated neoadjuvant chemoradiotherapy (nCRT) plus local excision (LE) as an alternative treatment strategy for patients with cT2N0 rectal cancer. METHOD: Fifty-six patients with cT2N0M0 rectal cancer who exhibited the following characteristics (an anal verge of ≤8 cm, tumor size of <30 mm, well- or moderately differentiated adenocarcinoma on biopsy) underwent LE following nCRT. Chemoradiotherapy was administered at 40 or 45 Gy in 20-25 fractions with concurrent oral UFT (tegafur/uracil; 400 mg/m2) or S-1 (tegafur/gimeracil/oteracil; 80 mg/m2). RESULTS: Fifty-five patients (98%) completed nCRT as planned. Histologically, the excision margin was negative in all patients, and four patients with ypT3 disease underwent total mesorectal excision. Recurrence was observed in 15 patients (27%), local recurrence in 7 (13%), and distant recurrence in 10 (18%). The salvage surgery was possible for the local recurrence group. The 5-year disease-free and overall survival rates were 68.4% and 84.9%, respectively. Multivariate analysis showed that only the tumor regression grade (TRG) was an independent risk factor for recurrence (p = 0.025). Although 7 (26%) out of 27 patients with a TRG of 3 or 4 developed local recurrence and 6 (22%) had distant metastasis, 25 patients with a TRG of 1 or 2 did not exhibit local recurrence, and only 1 (4%) experienced distant metastasis. CONCLUSION: nCRT plus LE may be an alternative treatment for patients with cT2N0 rectal cancer who achieved a TRG of 1 or 2. However, additional treatment was required in patients who achieved a TRG of 3 or 4.

Predictors and histological effects of preoperative chemoradiotherapy for rectal cancer and control of lateral lymph node metastasis.

INTRODUCTION: Standard treatment strategy for low rectal cancer in Japan is different from Western countries. Total mesorectum excision (TME) + lateral lymph node dissection (LLND) is mainly carried out in Japan, whereas neoadjuvant chemoradiotherapy (nCRT) + TME is selected in Western countries. There is no clear definition of preoperative diagnosis of lateral lymph node metastasis. If we can predict lateral lymph node swelling that can be managed by nCRT from lateral lymph node swelling that require surgical resection, clinical benefit is significant. In the current study we assessed characteristics of the lateral lymph node recurrence (LLNR) and LLND that can be managed by nCRT. PATIENTS AND METHODS: Patients with low rectal cancer (n = 168) underwent nCRT between 2009 and 2016. We evaluated CEA, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and lateral lymph node short axis pre and post nCRT, respectively, and also evaluated tumor shrinkage rate, tumor regression grade (TRG). We evaluated the relationship between each and LLNR. RESULTS: LLND was not carried out all patients. Factors associated with LLNR were PLR and lymph node short axis pre and post nCRT. (p = 0.0269, 0.0278, p < 0.0001, p < 0.0001, respectively). Positive recurrence cut-off values of lateral lymph node short-axis calculated were 11.6 mm pre nCRT and 5.5 mm post nCRT. CONCLUSION: Results suggest that PLR before and after CRT was associated with control of LLNR, and LLND should be performed on lateral lymph nodes with short-axis of 5 mm and 11 mm pre and post nCRT.

Internal hernia caused by bridge formation between the medial and lateral segments of the liver: a case report.

BACKGROUND: Despite numerous reports on ischemic bowel obstruction caused by internal hernia, no case presentation has been reported of an internal hernia caused by a bridge formed between the medial and lateral zones of the liver. Herein, we report the first case of ischemic bowel obstruction caused by a hepatic bridge. CASE PRESENTATION: A 24-year-old man complaining of abdominal pain was referred to our hospital and admitted. Computed tomography showed formation of a closed loop of small bowel with a hernia orifice near the hilar region, and poor contrast of the prolapsed small bowel. We suspected ischemic bowel obstruction caused by an internal hernia with a fissure of the greater omentum as the hernia orifice, and performed emergency surgery. Laparoscopic observation revealed that the medial and lateral segments of the liver formed a bridge on the dorsal side at the liver portal, and that the small intestine was ischemic in the gap created between the bridge and the medial and lateral liver segments. A Meckel's diverticulum was also invaginated in the gap. The bridge was dissected out and the hernia orifice was opened to release the bowel obstruction. The small bowel was preserved and the Meckel's diverticulum was resected. The patient's postoperative course was uneventful. CONCLUSIONS: We experienced a case of ischemic bowel obstruction caused by hepatic bridge formation, which was successfully treated by laparoscopic surgery.

Classification of rectal cancer according to recurrence types - comparison of Japanese guidelines and Western guidelines.

BACKGROUND: Rectal cancer is characterized by more local recurrence (LR) and lung metastasis than colon cancer. However, the diagnosis of rectal cancer is not standardized as there is no global consensus on its definition and classification. The classification of rectal cancer differs between Japanese and Western guidelines. AIM: To clarify the characteristics of rectal cancer by comparing the tumor location and characteristics of rectal cancer with those of colon cancer according to each set of guidelines. METHODS: A total of 958 patients with Stage II and III colorectal cancer were included in the analysis: 607 with colon cancer and 351 with rectal cancer. Localization of rectal cancers was assessed by enema examination and rigid endoscopy. According to Japan guidelines, rectal cancer is classified as Rb (below the peritoneal inversion), Ra (between the inferior margin of second sacral vertebrae and Rb) or RS (between Ra and sacral promontory). RESULTS: There were no significant differences between RS rectal cancer and colon cancer in the rates of liver and lung metastasis or LR. Lung metastasis and LR were significantly more common among Rb rectal cancer (in Japan) than in colon cancer (P = 0.0043 and P = 0.0002, respectively). Lung metastases and LR occurred at significantly higher rates in rectal cancer measuring ≤ 12 cm and ≤ 10 cm than in colon cancers (P = 0.0117, P = 0.0467, P = 0.0036, P = 0.0010). Finally, the rates of liver metastasis, lung metastasis, and LR in rectal cancers measuring 11 cm to 15 cm were 6.9%, 2.8%, and 5.7%, respectively. These were equivalent to the rates in colon cancer. CONCLUSION: High rectal cancer may be treated with the same treatment strategies as colon cancer. There was no difference in the classification of colorectal cancer between Japan and Western countries.

Tumor-Infiltrating Lymphocytes in Biopsy Specimens Obtained 7 Days after Starting Chemoradiotherapy for Rectal Cancer Are Predictors of the Response to Chemoradiotherapy.

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision surgery is a standard treatment for locally advanced rectal cancer (LARC). Tumor-infiltrating lymphocytes (TILs) have been reported to be associated with tumor response; however, this remains to be established. We previously reported that histological changes on biopsy specimens obtained 7 days after starting nCRT are strong predictors of response to nCRT. METHODS: The subjects were 208 patients with LARC who received nCRT. TILs on hematoxylin-eosin staining together with immunohistochemical staining of lymphocyte surface markers including CD3, CD4, CD8, and FoxP3 were performed both on the biopsy specimens before and 7 days after starting nCRT. RESULTS: The proportions of patients with high densities of CD3+, CD4+, CD8+, and FoxP3+ cells 7 days after starting CRT were significantly lower than the respective values before starting nCRT (p < 0.0001, p < 0.0001, p = 0.0023, and p = 0.0046). In biopsy specimens obtained before treatment, high-density CD4+ cells and FOXP3+ cells were significantly associated with tumor shrinkage rate. High-density FOXP3+ cells were significantly associated with marked tumor regression. In biopsy specimens obtained 7 days after starting treatment, high-density CD4+ cells were significantly associated with marked tumor regression, tumor regression grade 1, and tumor shrinkage rate. High-density FoxP3+ cells were significantly associated with marked tumor regression and tumor shrinkage rate. CONCLUSIONS: In patients who received nCRT for LARC, the evaluations of immunohistochemical staining for CD4+ and FOXP3+ TILs were more intimately related to histological response to CRT and tumor shrinkage rates in biopsy specimens obtained 7 days after starting treatment than in biopsy specimens obtained before CRT.

Tissue-Infiltrating Lymphocytes as a Predictive Factor for Recurrence in Patients with Curatively Resected Colon Cancer: A Propensity Score Matching Analysis.

BACKGROUND: In patients with colorectal cancer, the rate of recurrence increases as the histologic stage progresses. However, the prediction of recurrence in individual patients is difficult. Many studies have reported on the relation between outcomes and tissue-infiltrating lymphocytes (TILs). The aim of our study was to clarify the relation between TILs and oncologic outcomes in patients with colon cancer using propensity score matching analysis. METHODS: The study group comprised 513 patients with colon cancer who received curative resection. By using propensity score matching for sex, age, tumor location, T stage, N stage, histologic type, and adjuvant therapy as conventional prognostic factors, 61 patients with recurrence and 61 patients with no recurrence were selected. Hematoxylin-eosin staining and immunohistochemical staining using CD3, CD8, CD4, and FoxP3 were performed for lymphocytes in the primary tissue. The results were evaluated separately in the whole tumor, the central part, and the invasive margin. RESULTS: The median follow-up period was 53 months. Among the 513 patients, 70 had recurrence and 443 had no recurrence. In the comparison of outcomes between the 61 patients with recurrence and the 61 patients with no recurrence, univariate analysis showed that the disease-free survival rate was significantly higher among the patients with positive TILs in the whole tumor and in the invasive margin (p = 0.016 and p = 0.012, respectively) and with CD8+ cells in the central part (p = 0.039) than among those with negative results. A multivariate analysis showed that TILs in the invasive margin (hazard ratio 1.81; 95% confidence interval, 1.03-3.05; p = 0.037) and CD8+ cell density in the central part (hazard ratio 1.76; 95% confidence interval, 1.07-2.93; p = 0.023) were prognostic factors that were independent from conventional prognostic factors. CONCLUSIONS: In patients with curatively resected colon cancer, TILs in the invasive margin and CD8+ cell density in the central part may be prognostic factors suggesting host antitumor immune response.

Oral S-1 with 24-h Infusion of Irinotecan plus Bevacizumab versus FOLFIRI plus Bevacizumab as First-Line Chemotherapy for Metastatic Colorectal Cancer: An Open-Label Randomized Phase II Trial.

BACKGROUND: FOLFIRI plus bevacizumab have been widely used as first-line treatment for metastatic colorectal cancer (mCRC). Pharmacokinetics and pharmacodynamics suggested a low dose of irinotecan given as a long-term infusion is expected to enhance antitumor activity. We conducted a randomized phase II study to compare oral S-1 with a 24-h infusion of irinotecan plus bevacizumab versus FOLFIRI plus bevacizumab. METHODS: The subjects comprised 120 chemotherapy-naïve patients with mCRC. The study group received a 24-h infusion of irinotecan at a dose of 125 mg/m2 on days 1 and 15, combined with oral S-1 80 mg/m2 on days 1-14 (24h-SIRI/B). The FOLFIRI/B group received irinotecan at a dose of 150 mg/m2, 5-fluorouracil given at a dose of 400 mg/m2 as a bolus injection and at a dose of 2,400 mg/m2 as a 46-h infusion, and 200 mg/m2 leucovorin on days 1 and 15. Bevacizumab was given at a dose of 5.0 mg/kg on days 1 and 15 in both groups. Treatment was repeated every 4 weeks. The primary endpoint was 1-year progression-free survival (PFS). Secondary endpoints were PFS, response rates (RR), overall survival (OS), and adverse events (AEs). RESULTS: From December 2013 through January 2018, 120 patients were randomly assigned, 61 patients to the 24h-SIRI/B and 59 patients to the FOLFIRI/B. The median follow-up period was 22.8 months. The 1-year PFS rate was 43.14% in the 24h-SIRI/B arm and 19.15% in the FOLFIRI/B arm (HR = 0.312 [95%CI 0.13-0.78], p = 0.01). The median PFS was 10.2 months (95%CI 8.8-14.3) and 10.0 months (95%CI 7.4-11.0), and the median OS was 29.7 months (95%CI 22.9-43.9) and 28.8 months (95%CI 18.4-ND), respectively (p = 0.3758, p = 0.8234). The overall RR was 86.3 and 61.7%, respectively (p = 0.0053). AEs were similar. CONCLUSIONS: Our results show that the 24h-SIRI/B regimen is an effective and reasonably well-tolerated regimen for the first-line treatment of mCRC.

A prospective clinical study assessing the presence of exfoliated cancer cells and rectal washout including tumors in patients who receive neoadjuvant chemoradiotherapy for rectal cancer.

PURPOSE: Rectal washout is performed in rectal cancer surgery to eliminate exfoliated cancer cells. Before rectal washout, a cross-clamp should generally be placed distal to the tumor. In some patients with lower rectal cancer, however, the tumor cannot be adequately isolated. We, therefore, hypothesized that neoadjuvant chemoradiotherapy (nCRT) can decrease the number of exfoliated cancer cells even after the rectal washout including tumors. METHODS: We prospectively studied 86 patients with rectal cancer who underwent proctectomy after nCRT. A cross-clamp was applied proximal to the tumor, and the rectum was washed with 2000 mL of physiological saline solution. The initial 100 mL used to wash the rectum was collected as a pre-washout sample. After the rectum was washed with the remaining 1900 mL, the solution remaining in the rectum was collected as a post-washout sample. Cells classified as class IV or higher according to the papanicolaou classification were considered to indicate a positive diagnosis. RESULTS: The cytological diagnosis was positive in pre-washout samples in 21 patients (24%) and post-washout samples in two patients (2%). CONCLUSION: In patients with rectal cancer, nCRT may decrease the number of exfoliated cancer cells in the rectum, and rectal washout including the tumor may be oncologically acceptable.

Distribution of Neuroendocrine Marker-Positive Cells in Colorectal Cancer Tissue and Normal Mucosal Tissue: Consideration of Histogenesis of Neuroendocrine Cancer.

BACKGROUND: Colorectal neuroendocrine carcinoma (NEC) is a rare disease, and mixed cases with colorectal adenocarcinoma also exist. The histogenesis of this disease remains unclear. We studied the numbers of neuroendocrine marker-positive cells in adenocarcinoma tissue and in normal -mucosal tissue to investigate the relation between adenocarcinoma and NEC and to discuss the histogenesis of NEC. METHODS: We studied a total of 354 curatively resected cases of stage II or III colon cancer and 36 cases of rectal cancer treated at the Tokai University Hospital between 2007 and 2012. Adenocarcinoma tissue and normal mucosal tissue were immunohistochemically stained with chromogranin A, synaptophysin, and CD56. Cases in which neuroendocrine marker-positive cells were found in cancer tissue were defined as positive. In normal mucosa, the numbers of positive cells per 15 high-power fields (HPF) were counted. RESULTS: Among the 390 cases, 181 cases had right sided colon cancer, 173 cases had left sided colon cancer, and 36 cases had rectal cancer. The rates of positive staining for chromogranin A, synaptophysin, and CD56 were significantly higher in the right sided colon than in the left sided colon, consistent with the preferred sites of NEC as reported previously. Cells positive for chromogranin A and synaptophysin in normal mucosa were significantly more common in the rectum and the left sided colon than in the right sided colon. No site-specific differences were found for CD56. CONCLUSIONS: Neuroendocrine marker-positive cells in colorectal cancer tissue are more common in the right sided colon, whereas neuroendocrine marker-positive cells in normal mucosa are more common in the rectum. These results suggest that NEC may arise from preceding adenocarcinomas.

Induction of CD3+ and FoxP3+ T Cells in Left-sided Colorectal Tumors After UFT/LV Chemotherapy.

BACKGROUND/AIM: Immune checkpoint inhibitors are mainly used for right-sided, microsatellite instability-high colorectal tumors. In this study, the effects of oral uracil-tegafur plus leucovorin (UFT/LV) chemotherapy on the gene expressions of four immunotherapy targets and the amounts of tumor-infiltrating lymphocytes (TILs) were investigated. PATIENTS AND METHODS: Data of 260 patients with stage II or stage III colorectal cancer were analyzed. Gene expression and amount of TILs were evaluated using real-time reverse transcription polymerase chain reaction (CRT-PCR) assay and immunohistochemical staining, respectively. RESULTS: Expression of CTLA4 and LAG3 in tumor tissues was significantly increased after UFT/LV chemotherapy, but only in left-sided tumors. The percentage of high-TIL, high-CD3 and high-FoxP3 patients in the UFT/LV group was significantly higher than that in the control group, only in left-sided tumors. CONCLUSION: The increase in TILs count, especially of CD3+ T cells and FoxP3+ regulatory T cells, after UFT/LV chemotherapy were specific to left-sided colorectal cancers.

Perforated gastrointestinal stromal tumor in the small intestine: A rare case of Torricelli-Bernoulli sign.

The Torricelli-Bernoulli sign is a computed tomography (CT) finding that occurs when ulceration/necrosis of a submucosal gastrointestinal tumor releases a stream of air bubbles into the intestinal lumen. A 75-year-old man developed acute abdominal pain at night and presented to a local doctor. Acute abdomen was diagnosed and he was referred to the Emergency Department at Tokai University Oiso Hospital. On CT scans, disseminated intestinal tumor-like lesions were seen in the right lower abdomen. The Torricelli-Bernoulli sign and free intraabdominal gas were observed, so perforation of an intestinal tumor was diagnosed and emergency surgery was performed. At operation, there was scanty opaque ascites in the right lower abdomen and an ileal tumor associated with nodules that suggested peritoneal dissemination. Partial resection of the ileum was performed and peritoneal lavage was conducted. The patient was discharged on postoperative day 11. Histopathological examination revealed a high risk gastrointestinal stromal tumor. The abdominal nodules were metastases, indicating that the tumor was Stage IV. The patient is currently on treatment with an oral tyrosine kinase inhibitor (imatinib).

The Number of Natural Killer Cells in the Largest Diameter Lymph Nodes Is Associated with the Number of Retrieved Lymph Nodes and Lymph Node Size, and Is an Independent Prognostic Factor in Patients with Stage II Colon Cancer.

OBJECTIVE: We previously reported that the largest diameter of retrieved lymph nodes (LNs) correlates with the number of LNs and is a prognostic factor in stage II colon cancer. We examine whether T, B, and natural killer (NK) cells in LNs are related to the number of LNs and survival. METHODS: The subjects comprised 320 patients with stage II colon cancer. An LN with the largest diameter was selected in each patient. The positive area ratios of cells that stained for CD3 and CD20, and the numbers of CD56-positive cells were measured. RESULTS: The CD3-positive area ratio was 0.39 ± 0.08 and CD20-positive area ratio was 0.42 ± 0.10. The mean number of CD56-positive cells was 19.3 ± 22.7. The area ratios of B cells and T cells and the number of NK cells were significantly related to the sizes of the largest diameter LNs. The number of NK cells significantly correlated with the number of LNs and was an independent prognostic factor. On multivariate analysis, pathological T stage (T4 or T3; HR 4.71; p < 0.001) and the number of CD56-positive cells (high or low; HR 0.22; p < 0.001) were found to be independent prognostic factors. CONCLUSIONS: The number of NK cells in the largest diameter LNs can most likely be used as a predictor of recurrence.