[A Case of Laparoscopic Abdominoperineal Resection and Perineal Reconstruction for Signet-Ring Cell Carcinoma with Skin Invasion Derived from the Anal Gland].

A 56-year-old man was referred to our hospital with an awareness of anal tumor. The tumor extended from the anal verge to the back of left testicle. Colonoscopy showed no tumor in the rectum and the anal canal. Biopsy showed mucus- producing adenocarcinoma(sig), and we diagnosed anal canal adenocarcinoma with immunostaining. Laparoscopic abdominoperineal rectal resection and perineal reconstruction with the V-Y fasciocutaneous flap closure technique. The patient had no major postoperative complications, and was discharged on 23rd postoperative day. Pathological examination revealed that the tumor was pT3N0M0, pStage ⅡB. The patient received adjuvant chemotherapy with CAPOX and has survived 12 months without recurrence. Immunostaining may be used to diagnose the signet-ring cell carcinoma without tumor of anal canal. In addition, reconstruction of the perineum for large anal tumors is useful.

[A Case of Robot-Assisted Abdominoperineal Resection with Prostatectomy for Locally Advanced Rectal Cancer].

The patient was referred to our hospital because of bloody stool and anorectal pain, and a colonoscopy revealed a tumor in the lower rectum. Although no distant metastasis was found, the tumor was suspected to have invaded the distal prostate. Neoadjuvant chemoradiotherapy(45 Gy/25 Fr with S-1)resulted in tumor shrinkage and symptomatic improvement, however, the primary tumor remained in close proximity to the prostate and urethra. Thus, we performed a robot-assisted abdominoperineal resection and Retzius-sparing prostatectomy in collaboration with the urology department. The surgical margins were negative and radical resection was achieved. Although minor vesicourethral anastomotic leakage was observed, it recovered conservatively. The patient has been alive 1 year postoperatively without recurrence. The patient initially had urinary incontinence, but it gradually improved. Although a total pelvic resection could have been considered, the robot-assisted surgery made it possible to preserve the urinary tract. The future application of robot-assisted surgery in extended surgery is expected.

Resection rate curves by location along the small intestine provide perspectives on characteristics of Crohn's disease.

AIM: Crohn's disease (CD) can affect any part of the gastrointestinal tract; however, the frequency of CD lesions differs by location. This work aimed to examine resection rates by location to clarify locational characteristics of the small intestine in surgical CD cases. METHOD: This was a single-centre retrospective case note review of patients who had undergone resection for CD affecting the small intestine between January 2014 and February 2020. Operative details, including length of the small intestine, location and extent of the resection, identified the pattern of disease. By normalizing these data the resection rate along the length of the intestine was calculated to create resection rate curves. RESULTS: One hundred and twenty six surgical cases were identified. The resection rate curves could be divided into two types: exponential and bimodal. For primary surgery, this depended on whether or not surgery was limited to an ileocolic resection. At subsequent surgery, a previous ileocaecal resection influenced the pattern of disease. The peaks of the bimodal curve were located at the proximal and distal ileum. CONCLUSION: CD patients requiring resection of the small intestine can be divided into terminal ileum type (exponential type) and proximal ileum type (bimodal type). In the future this analytical method may help predict the site of any recurrent disease but also provides a new perspective on the disease.

[A Case of Rectal Cancer with Disseminated Intravascular Coagulation Successfully Treated with Emergent Chemotherapy].

A 70's woman complaining blood stool and lower abdominal pain visited a local doctor and was given the diagnosis of rectal cancer by colonoscopy. CT, MRI, and bone scintigraphy revealed multiple lymph node and bone metastasis and peritoneal dissemination. She had developed disseminated intravascular coagulation(DIC)during hospitalization, and the cause was considered to be disseminated carcinomatosis of the bone marrow. Thus, we emergently started chemotherapy with mFOLFOX6, in conjunction with anticoagulation therapy, and the DIC was resolved 11 days after the introduction. Partial response was achieved and the chemotherapy has been continued after 5 months from the onset of the DIC. Since the prognosis of solid tumor patients who developed DIC has been reported to be extremely poor, prompt introduction of chemotherapy should be considered.

[A Case of Curative Resection after Neoadjuvant Chemotherapy for Locally-Advanced Sigmoid Colon Carcinoma with Urinary Bladder Invasion].

A 56-year-old man was referred to our hospital for multidisciplinary treatment of advanced sigmoid colon carcinoma with a suspected bladder invasion. The patient received 8 courses of modified Leucovorin, fluorouracil, and oxaliplatin (mFOLFOX6)plus panitumumab as neoadjuvant chemotherapy for reliable and safe radical resection after ileostomy construction. There was a significant reduction in the tumor size following chemotherapy; hence, low anterior resection was performed. In addition, since preoperative and intraoperative findings suggested bladder invasion, a total cystectomy with ileal conduit urinary diversion was performed. The pathological diagnosis was ypT4b, N0, M0, and ypStage Ⅱc, with all surgical margins being negative. Subsequently, the patient received adjuvant chemotherapy with 4 courses of mFOLFOX6, and his condition improved with no incidence of cancer recurrence following 8 months after the operation. Neoadjuvant chemotherapy for locally advanced colon cancer is one of the effective treatments for reliable and safe radical resection.

Increased Quinolone-Resistant Mutations of gyrA and parC Genes after Pouchitis Treatment with Ciprofloxacin.

BACKGROUND: Oral antibiotics, such as ciprofloxacin (CFX), are widely used for the treatment of acute and chronic pouchitis. Most bacterial mutations that confer quinolone resistance are at Ser-83 and Asp-87 in the gyrA gene and Ser-80 and Glu-84 in the parC gene. METHODS: We obtained 51 stool samples from 43 patients who were diagnosed with ulcerative colitis and underwent ileal pouch-anal anastomosis. Patients were divided into 2 groups: 13 patients with CFX treatment of pouchitis and 30 patients without pouchitis. After extraction of fecal DNA, the amount of Escherichia coli 16S rRNA, gyrA, and parC gene DNA were measured using real-time polymerase chain reaction (PCR). Possible mutations at gyrA 83 and 87 and at parC 80 and 84 were investigated by PCR cloning and sequencing, and mutation rates were quantified by rapid PCR-restriction fragment length polymorphism. RESULTS: Samples from both CFX-treated and -untreated patients had comparable levels of gyrA and parC gene DNA. Nucleic acid and amino acid mutations were identified at gyrA 83 and 87, and at parC 80 and 84. We successfully quantified mutation rates at gyrA 83 and 87, and at parC 84, all of which were significantly higher in samples from CFX-treated patients (70, 84, and 38%) than from CFX-untreated patients (13, 11, and 5%). CONCLUSION: E. coli in patient pouches may have mutations in their gyrA and parC genes that produce CFX resistance. Mutation rates of these genes were significantly higher in samples from CFX-treated patients. This study contributes to understanding the decrease and loss of CFX effectiveness against pouchitis.

[A Case of Sigmoid Colon Cancer with Thrombotic Microangiopathy].

A 50's man was referred to our hospital because of sigmoid colon cancer with multiple liver metastases and para-aortic lymph node metastases. Although blood test showed elevated D-dimer(50 µg/mL), there was no significant thrombus in contrast-enhanced CT scan. Since cancer pain and symptoms of bowel obstruction had continued after endoscopic stent placement, we resected primary lesion. Despite anemia and elevated D-dimer level had persisted after the operation, there were no obvious bleeding source nor thrombus. Continuous intravenous heparin infusion was started for hypercoagulability. Then, D-dimer and CRP levels were promptly decreased. Since schizocyte and giant platelets were observed in peripheral blood smear, he was eventually diagnosed with thrombotic microangiopathy as a paraneoplastic syndrome. However D- dimer and CRP levels were re-elevated, and it seemed to be necessary to control cancer progression. Thus, cetuximab monotherapy was started considering his performance status. After starting cetuximab, fever and CRP level were immediately improved. Cetuximab appeared to be very effective, but he died of acute subdural hematoma. Continuous intravenous heparin infusion was supposed to be effective in the treatment of thrombotic microangiopathy along with the management of cancer.

[Bladder-Sparing Surgery with Preoperative Chemotherapy for Rectal Cancer with Urinary Bladder Involvement-A Case Report].

A 65-year-old male was diagnosed with rectal cancer invading the urinary bladder, swollen para-aorticlymph nodes, and multiple liver metastases in abdominal CT. After 8 courses of mFOLFOX6 plus panitumumab, the rectal cancer, para-aortic lymph nodes metastasis, and liver metastases decreased significantly in size. Rectal cancer and liver metastases were considered resectable, hence low anterior resection of the rectum was performed. Intraoperative frozen section analysis showed negative metastaticinvolvement of the para-aorticlymph nodes and surgical margins of the urinary bladder; therefore, the urinary bladder was completely preserved. Partial resection of the liver was performed 2 months later. In conclusion, the patient showed good surgical and quality of life results. Thus, the bladder-sparing strategy with preoperative chemotherapy could be considered for appropriately selected rectal cancer patients with urinary bladder involvement.

[A Case of Radically Resected Sigmoid Colon Cancer with Bladder Invasion after Chemotherapy and Weight Loss in an Extremely Obese Patient].

A 30's extremely obese patient(body mass index: BMI 45 kg/m2)was referred to our hospital with a chief complaint of bloody urine and stool. Colonoscopy revealed a sigmoid colon tumor. Barium enema examination revealed stenosis of the sigmoid colon. CT scan showed a tumor in the sigmoid colon, with bladder invasion. The para-aortic lymph node was partially swollen. We considered surgery to be high risk because of the patient's severe obesity. Therefore, we decided to examine the possibility of radical surgery followed by chemotherapy(mFOLFOX6/cetuximab)with weight reduction. Following this, the tumor had shrunk remarkably, and the patient's BMI decreased from 45 kg/m2 to 39 kg/m2. The visceral fat area was reduced from 298 cm2 to 199 cm2 at the umbilical level. We then performed a sigmoid colectomy with partial resection of the bladder. Thus, chemotherapy combined with weight loss enabled us to perform radical surgery safely for a locally advanced sigmoid colon cancer in a patient with severe obesity.

[A Case of Curatively Resected Rectal Cancer with Preservation of Urinary Function after Chemotherapy].

A55 -year-old man was diagnosed with rectal cancer invading the urinary bladder and swollen para-aortic lymph nodes. Since distant metastasis was indicated and total pelvic exenteration was required, 6 courses of chemotherapy with mFOLFOX6 plus panitumumab were performed. After the chemotherapy, the rectal cancer and para-aortic lymph nodes significantly decreased in size, and novel distant metastasis was not observed in CT scans. Therefore, the tumor was considered resectable, and operation was performed. Intraoperative frozen section analysis showed that the para-aortic lymph nodes and surgical margin of the urinary bladder were negative. Thus, low anterior resection of the rectum and partial resection of the urinary bladder were performed. R0 resection was pathologically achieved, and adjuvant chemotherapy with S-1 was administered for 6 months. The patient is alive without recurrence for 10 months. Upfront chemotherapy can be a strategy for advanced rectal cancer with urinary bladder invasion to avoid total pelvic exenteration.

[A Case of Solitary Residual Lateral Pelvic Lymph Node Metastasis Despite Complete Response of Primary Rectal Cancer Followed by Neoadjuvant Chemoradiotherapy].

A 45-year-old woman was referred to our hospital complaining of diarrhea. Colonoscopy showed a rectal tumor. Histological examination showed moderately differentiated adenocarcinoma. A CT scan revealed a tumor extending from the lower rectum to the anal canal with a lateral pelvic lymph node(LPLN)swelling. We administered neoadjuvant chemoradiotherapy (45 Gy/25 Fr, S-1 80mg/m / 2/day)and the tumor and LPLN shrank remarkably, with a clinically complete response by CT and PET-CT. We then performed abdominoperineal resection with D3 lymph node and bilateral LPLN dissection. Pathological examination revealed complete disappearance of the cancer cells in the primary site, while lymph node metastasis was detected in one LPLN. We report here a rare case in which LPLN metastasis remained despite the pathological complete response of the primary tumor.

[A Case of Curatively Resected Locally Recurrent Rectal Mucinous Adenocarcinoma Followed by Preoperative Chemoradiotherapy].

A 60s man was diagnosed with rectal cancer and underwent low anterior resection of the rectum. The pathological diagnosis was mucinous adenocarcinoma, pT3(SS), pN0, pM0, pStage Ⅱ. Two years after the primary surgery, contrast-enhanced CT showed local recurrence on the oral side of the anastomosis. As the tumor had invaded the left seminal vesicle and coccygeus muscle, neoadjuvant chemoradiotherapy(NACRT)(S-1 80mg/m / 2 plus 45 Gy/25 Fr)was performed. After NACRT, abdominoperineal resection, including the left seminal vesicle, coccygeus muscle, and coccygeal bone, was performed. Pathological examination showed a histological response of Grade 2 and that R0 resection was achieved. Although the only radical treatment of locally recurrent rectal cancer is R0 resection, we performed R0 resection with Grade 2 histological response to NACRT.

[A Case of Peritoneal Metastasis Resection from GIST of the Small Intestine with Focal Resistance Against Imatinib Mesylate].

A 69-year-old man was referred to our institute for the surgical resection of focal resistant peritoneal GIST during imatinib administration. He had been diagnosed with GIST of the small intestine with liver and peritoneal metastases, and imatinib treatment was initiated. Shortly after imatinib administration, the primary lesion perforated, and thus, partial resection of the small intestine was performed. Imatinib treatment was resumed after the first surgery, and he achieved partial response. However, computed tomography scans obtained 7 months after the first surgery showed focal progression, a peritoneal metastasis near the right kidney. Under the diagnosis of focally imatinib-resistant GIST, local resection of the metastatic tumor was performed. In this case, an exon 11 mutation of c-kit was noted initially. After the imatinib treatment, an additional point mutation was observed in exon 18 that caused resistance to imatinib. Therefore, imatinib treatment was reinitiated after the second surgery, and other metastases were well controlled. In case of GIST with multiple metastases, appropriate treatment should be selected based on the resistance of each lesion.

[Two Cases of Locally Recurrent Rectal Cancer Successfully Treated by Carbon Ion Radiotherapy].

Case 1: A female patient in her 60s underwent laparoscopic intersphincteric resection for rectal cancer. After 42 months, the serum level of carcinoembryonic antigen(CEA)was elevated, and PET-CT showed a locally recurrent rectal cancer that increased FDG-uptake. Carbon ion radiotherapy(CIRT)(73.6 GyE/16 Fr)was performed. Serum CEA level and FDG-uptake were normalized. No regrowth of tumor has been found for 12 months. Case 2: A female patient in her 60s underwent abdominoperineal resection for rectal cancer. After 42 months, the serum level of CEA was elevated, and CT revealed a local recurrence of rectal cancer. Subsequently, the tumor was resected; however, resection margin was microscopically positive. Therefore, chemoradiotherapy(S-1, 60 Gy)was performed. At 31 months after local resection, a re-recurrent tumor was noted in her left ischium. Therefore, CIRT(70.4 GyE/16 Fr)was performed. Serum CEA level and FDG-uptake were normalized. No regrowth of tumor has been found for 24 months. CIRT is an effective therapy for locally recurrent rectal cancer.

[A Case of Laparoscopically Resected Giant Rectal Cancer Following Neoadjuvant Chemoradiotherapy].

A woman in her 40s who presented to a local hospital with bloody stool was referred to our hospital. Colonoscopy showed a rectal tumor, and histological examination showed moderately differentiated adenocarcinoma. CT and MRI revealed that the tumor was 65mm in diameter with no distant metastasis. After the construction of ileostomy, neoadjuvant chemoradiothera- py(NACRT: 45 Gy/25 Fr, S-1 80mg/m2)was performed. The tumor shrank remarkably, and then we performed laparoscopy- assisted low anterior resection. Pathological examination revealed complete disappearance of the cancer cells in the primary site and no appearance of cancer cells in all dissected lymph nodes. NACRT has been recently reported to provide pathological complete response, and these patients are supposed to have a good prognosis. In our case, NACRT enhanced the performance of laparoscopic curative resection while preserving anal function. NACRT should contribute to the curative resection while preserving anal function in patients with locally advanced rectal cancer.

[A Small Rectal Neuroendocrine Tumor of Less Than 5mm with Lymph Node Metastasis].

According to the treatment guideline for rectal neuroendocrine tumor(NET), tumor with a diameter ofC10mm should be resected endoscopically, while tumor with a diameter of>10mm should be resected surgically with lymph node dissection. We experienced a case of a rectal NET with a diameter of 5mm with lymph node metastasis. A 69-year-old man underwent colonoscopy for positive fecal occult blood test. The colonoscopy revealed a submucosal tumor(SMT)with a diameter of 5 mm in the lower rectum. An endoscopic mucosal resection(EMR)was performed after SMT was diagnosed as NET by biopsy. Histopathological findings were NET-G1, 4.5×2.5 mm, v(+), ly(+). Then, laparoscopically assisted rectal resection with D2 lymph node dissection was performed. In histopathological examination, no tumor residue was observed in the specimu; however, a regional lymph node metastasis was detected. Risk factors of lymph node metastasis with rectal NET are a diameter of>10 mm, recessed or ulcerated surface, and lymphovascular invasion. However, we have to keep in mind that lymph node metastasis may occur even in small rectal NET with a diameter of ≤10mm.

Gastrointestinal toxicities of 5-fluorouracil increase the proportion of regulatory T cells in intestinal tract: advantages of alternate-day S-1 administration.

BACKGROUND: 5-Fluorouracil (5-FU), a core anticancer agent for malignancies, induces gastrointestinal (GI) toxicities. Despite recent advances in tumor immunology, it still remains unknown how GI toxicities affect antitumor immunity. S-1 is a tegafur-based oral 5-FU prodrug which has been widely introduced in Japan and other countries. The alternate-day S-1 administration has been proposed to minimize its GI and other toxicities without reducing its anticancer efficacy. METHODS: In this study, two S-1 administration regimens were compared in mice to evaluate their impact of GI toxicities on immunity. In the daily group as a standard administration model, S-1 was administered for 14 days on and 14 days off, and in the alternate-day group as a non-GI toxicity model, S-1 was administered every other day for 28 days. As well as physical findings, regulatory T cells, Th1 cells and other cells in murine lymphoid tissues were analyzed with flow cytometry. RESULTS: Only the daily group exhibited body weight loss and GI toxicities. In the daily group, a proportion of regulatory T cells in the intestinal lymphoid tissue were demonstrated to be six-fold higher than in the control without S-1, and the proportion of Th1 cells showed a decreasing trend. However, the alternate-day group exhibited almost no change in T-cell subsets. CONCLUSION: GI toxicities of 5-FU may have a negative influence on antitumor immunity due to increased proportions of regulatory T cells and decreased proportions of Th1 cells. The alternate-day S-1 administration may be a useful regimen with its minimal influence on T-cell subsets.

Usefulness of alternate-day administration of S-1 and leucovorin in a xenograft mouse model of colorectal cancer: a shorter drug-free interval leads to more efficient antitumor effects.

BACKGROUND: A clinical trial of S-1 with leucovorin (S-1/LV) in metastatic colorectal cancer (CRC) patients demonstrated promising efficacy; however, the gastrointestinal toxicities were so severe that it has not been applied in the clinical setting. On the other hand, alternate-day administration of S-1 has been proposed to attenuate the adverse events without reducing its anticancer activity. Our present study was conducted to confirm the feasibility of alternate-day administration of S-1/LV in in vivo xenograft tumor models. METHODS: Mice were treated with S-1/LV in a daily group (2 weeks of administration followed by 2 weeks of withdrawal) or an alternate-day group (administration on alternate days for 4 weeks), then the mice were killed and the xenograft tumors were resected. We compared body weight changes, condition of feces, mucosal injury and myelosuppression and assessed adverse reactions, tumor volume, tumor growth inhibition (TGI) and expression of Ki67, TUNEL, cIAP2 and XIAP to evaluate the antitumor activity and tumor apoptosis. RESULTS: Severe weight loss, diarrhea, mucosal injury and myelosuppression were observed only in the daily group; however, some myelosuppression was also observed in the alternate-day group. The TGI in the alternate-day group was better than in the daily group, possibly resulting from apoptosis due to the suppression of cIAP2 but not XIAP. CONCLUSION: Our findings suggest that alternate-day administration of S-1/LV for CRC treatment can achieve high antitumor activity without severe adverse reactions, and we propose that clinical trials with this regimen should be conducted in CRC patients.

Diagnostic utility of EUS-FNA in distinguishing hepatocellular carcinoma from gastric submucosal tumor: A case report.

INTRODUCTION AND IMPORTANCE: Extrahepatically growing hepatocellular carcinoma (HCC) account for only 0.3 %-2.4 % of all hepatocellular carcinoma cases. We present the rare case of a patient in whom endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was used to distinguish an extrahepatically growing HCC from a gastric submucosal tumor. CASE PRESENTATION: The patient was a 44-year-old man who underwent an esophagogastroduodenoscopy (EGD) and was found to have a submucosal tumor (SMT). A gastrointestinal stromal tumor was suspected. Computed tomography (CT) showed an unclear connecting between the tumor and the liver. On immunohistochemical analysis, the tumor cells were positive for CK7, PIVKA-II, and glypican-3, and negative for C-kit. Based on these findings, HCC was suspected, and ethoxybenzyl diethylenetriamine-enhanced magnetic resonance imaging (EOB-MRI) was performed. EOB-MRI revealed the connecting of the tumor and the liver. Thus, the patient was diagnosed as having an extrahepatically protruding HCC, and laparoscopic S2 partial hepatectomy was performed. Pathologically, the tumor was identified as a moderately differentiated HCC. According to the 8th edition of the UICC TNM Classification, the tumor was classified as T1bN0M0 and stage IB. CLINICAL DISCUSSION: Owing to its rarity, the diagnosis of an extrahepatically protruding HCC is often difficult when the differentiation of a gastric SMT and HCC is unclear on CT. As in this case, if an HCC is also differentiated on hematoxylin and eosin staining after EUS-FNA, immunohistochemistry findings can help in the diagnosis. CONCLUSION: The findings show that EUS-FNA could be helpful for diagnosis when an HCC needs to be differentiated from a gastric SMT.