The patient is a 45-year-old woman. She was aware of a right breast mass and consulted a referring physician. She was referred to our department for close examination and treatment. No axillary lymph node metastasis or distant metastasis was suspected on imaging examination, and a diagnosis of right breast cancer(cT2N0M0, Stage ⅡA)was made. The subtype was Luminal type with weakly positive ER. Preoperative chemotherapy was considered, but the patient underwent partial mastectomy and sentinel node biopsy. Histopathologically, the tumor cells were irregular with spindle-shaped nuclei, and the diagnosis of metaplastic breast cancer was made. The postoperative diagnosis was pT2, N0(sn), M0, Stage ⅡA. Metaplastic breast cancer is rare, accounting for approximately 1% of all malignant mammary tumors, and is considered to be a disease with a poor prognosis. There are reports that chemotherapy is ineffective, and there is no established treatment for this disease. We report the treatment course of this case with some discussion of the literature.

A 78-year-old male presented with circumferential stenosis in the gastric antrum and was diagnosed with signet cell carcinoma via biopsy. Contrast-enhanced CT revealed cT4aN0M0, cStage ⅡB, and he was referred to our department for surgery. Although pylorus-preserving gastrectomy was initially planned, extensive pancreatic invasion led to the decision for an unresectable diagnosis, and a gastrojejunostomy was performed instead. Approximately 1 month postoperatively, SOX plus nivolumab therapy was initiated without adverse events, resulting in stable disease(SD)after 12 courses over 10 months. After 13 months(15 courses), the patient experienced vomiting, diagnosed as gastrojejunostomy stenosis due to peritoneal dissemination. Given poor performance status, the patient transitioned to best supportive care(BSC). During follow-up, the patient gradually resumed oral intake. Ten months after discontinuing SOX plus nivolumab therapy, a CT scan showed primary tumor reduction and disappearance of peritoneal dissemination nodules, suggesting pseudo progression. The patient declined further surgery or chemotherapy and remains under outpatient observation.

The patient was a 76-year-old female who presented with pain during urination and turbid urine(containing fecal matter). She was referred to our urology department from a local clinic. Imaging findings indicated sigmoid colon cancer with bladder invasion. Total colonoscopy revealed a circumferential advanced sigmoid colon cancer. Abdominal contrast-enhanced computed tomography(CT)showed wail thickening of the sigmoid colon wall, with unclear demarcation from the bladder. The preoperative diagnosis was cT4b(bladder), N1b, M0, cStage Ⅲc. After construction of a colostomy, 4 course of capecitabine plus oxaliplatin with bevacizumab therapy were performed as neoadjuvant chemotherapy. Since response evaluation was partial response(PR), the pathological diagnosis was ypT4b(small intestine), N1a, M0, ypStage Ⅲc, with histological effect classificatory was 2. Postoperatively, 2 course of capecitabine plus oxaliplatin therapy and 1 course of capecitabine therapy were performed for adjuvant chemotherapy, has no relapsed for 14 months.

The patient was an 81-year-old man. He underwent laparoscopic rectal resection and hepatectomy in 2 stages for Rb rectal cancer and synchronous liver metastasis, followed by adjuvant chemotherapy. One year after the hepatectomy, the cancer metastasized to liver and lung, and a second hepatectomy and right lung partial resection were performed in 2 stages, along with preoperative and postoperative chemotherapy. One year after the lung partial resection, the cancer metastasized to right diaphragm. Since it was isolated, we decided to perform local resection, and performed a J-shaped thoraco-laparotomy. The tumor was located mainly in the diaphragm and was attached to the liver resection surface and the right lung, so we performed local resection by partially resecting the liver and lung. The pathology showed moderately to well-differentiated adenocarcinoma, a finding that was not inconsistent with metastasis of colorectal cancer. The patient has been recurrence-free for 2 years and 6 months since the diaphragmatic resection, and has survived for 5 years and 2 months since the initial surgery. We report a case of long-term survival after four surgeries for oligometastasis of rectal cancer, including diaphragmatic metastasis.

We report a case of thoracic aortic thrombosis that developed during preoperative 5-fluorouracil plus cisplatin(FP)therap y for esophageal cancer. Esophagectomy was performed after continued FP therapy along with anticoagulant therapy. The patient was an 80-year-old man diagnosed with thoracic esophageal cancer(Mt, cT3rN1M1a, cStage ⅢA). He was started on the FP regimen as neoadjuvant chemotherapy. Contrast-enhanced computed tomography(CT)after the first course of chemotherapy showed thoracic aortic thrombosis. FP chemotherapy was continued, and rivaroxaban was administered as an anticoagulant therapy. Preoperative CT revealed nearly complete thrombus resolution of the thrombus. The patient underwent a thoracoscopic esophagectomy with two-field lymph node dissection for esophageal cancer and was discharged after an uneventful postoperative course. There was no recurrence of aortic thrombosis.

The patient was a 73-year-old female with left lower abdominal pain. Colonoscopy revealed a tumor in the transverse colon, which was biopsied and diagnosed as a well-differentiated adenocarcinoma. Computed tomography revealed incomplete formation of the ligament of Treitz, with the small bowel located in the right abdomen and the ascending colon along the midline. The superior mesenteric vein(SMV)was positioned on the left side of the superior mesenteric artery(SMA). The tumor was located in the central part of the transverse colon. The patient was diagnosed with transverse colon cancer with intestinal malrotation before surgery. Laparoscopic partial colectomy(of the transverse colon)was performed. The lymph nodes were dissected from the right margin of the SMV. The middle and right colic arteries were severed, and D3 lymph node dissection was performed. The colon was found to have shifted to the left side, with extensive adhesions between the omentum and mesocolon. The postoperative pathological diagnosis was tub1, pT3, pN0, pM0, and pStage Ⅱ a. Intestinal malrotation was diagnosed preoperatively, and unusual vascular positioning was identified. Consequently, we were able to perform safe and adequate lymph node dissection during laparoscopic surgery.

The patient was a 72-year-old woman with a history of surgery for uterine, bladder, left breast, and rectal cancers. The patient was admitted to the emergency department due to abdominal pain and vomiting. Abdominal and pelvic computed tomography showed a mass lesion and bowel obstruction at the end of the ileum, and positron emission tomography showed a mass lesion with accumulation in the same area of the pelvis. The patient was referred to our department for surgical treatment. The tumor at the end of the ileum invaded the ileal conduit, abdominal wall, right-sided colon, and mouth of the ileum, and a right hemicolectomy of the colon was performed. Another mass was palpated in the pelvic jejunum during examination, and partial resection of the small intestine was performed simultaneously. The tumor at the end of the ileum was diagnosed as diffuse large B-cell lymphoma, whereas the jejunal tumor was diagnosed as tubular adenocarcinoma. Synchronous double cancer of malignant lymphoma of the ileum and carcinoma of the jejunum is rare. Herein, we report this case and review the relevant literature.

A 66-year-old man was suspected of having an intestinal obstruction caused by a tumor in the small intestine after a close examination of vomiting and abdominal pain. Intestinal decompression was performed using an ileus tube, and small bowel endoscopy revealed a circumferential type 2 tumor of the ileum and a poorly differentiated adenocarcinoma on biopsy. The patient was referred to our department with a diagnosis of primary ileal cancer(cT2N1M0, cStage ⅢA). The patient underwent laparoscopic partial resection of the small intestine and lymph node dissection. Partial resection of the small intestine was performed 10 cm from the primary tumor, and lymph node dissection was performed up to the left margin of the SMV. The postoperative diagnosis was primary ileal cancer(pT3N1aM0, pStage ⅢA). The patient was administered CapeOX as adjuvant chemotherapy for 6 months. The patient has been alive since then without any recurrence. We report a case of ileal cancer that was treated with surgical therapy and postoperative adjuvant chemotherapy, with no recurrence.

A 70-year-old male patient presented with epigastric pain. Subsequent evaluation revealed a cystic lesion in the head of the pancreas. After 1 year, the cyst had enlarged and a nodular shadow appeared within it, prompting a referral to our hospital. CT imaging revealed a 65 mm cystic lesion extending from the head to the uncinate process of the pancreas, located posterior to the portal vein. Additionally, an indistinct nodule was apparent inside the cyst. Based on a diagnosis of invasive intraductal papillary mucinous carcinoma, pancreaticoduodenectomy was performed. Intraoperative findings revealed that the uncinate process of the pancreas, which was continuous with the tumor, was fused with the dorsal pancreas. The dorsal pancreas, including the main pancreatic duct, was dissected first. Then, the uncinate process was resected from the dorsal pancreas at the fusion site using a linear stapler. Postoperatively, the patient developed a Grade B pancreatic fistula, which was successfully managed with conservative treatment. It has been reported that the portal annular pancreas poses a higher risk of postoperative pancreatic fistula following pancreaticoduodenectomy. This case highlights the challenges in the preoperative diagnosis of portal annular pancreas when a tumor is located in the uncinate process of the pancreas.

Gastric schwannoma is a rare primary gastric tumor, with several reports of malignancy. We report the case of a 76-year-old woman and conducted a literature review. The patient complained of epigastric pain and was referred to our gastroenterology department by a local doctor. Upper gastrointestinal endoscopy revealed a 30 mm submucosal tumor in the greater curvature of the middle part of the stomach. Endoscopic ultrasound-guided fine-needle aspiration was performed, and immunohistochemical staining confirmed the diagnosis of gastric schwannoma. Abdominal contrast computed tomography revealed the swelling in the surrounding lymph nodes, and fludeoxyglucose F18(FDG)positron emission tomography showed FDG accumulation in the primary lesion. Although biopsy confirmed that the tumor was a schwannoma, not a gastrointestinal tumor or another malignant tumor, laparoscopic radical distal gastrectomy with D2 lymph node dissection was performed. The postoperative course was uneventful, and the patient was discharged on the 10th postoperative day. Histopathological diagnosis showed no lymph node metastasis, but the MIB-1 index was high(10.9%), indicating a diagnosis of high-grade malignant schwannoma. The patient has been undergoing outpatient follow-up for approximately 2 years without recurrence. Gastric schwannoma is a rare primary gastric tumor, and radical surgical procedures should be carefully considered. Further collection and analysis of these cases are necessary in the future.

We report a case of right locally advanced breast cancer in an 84-year-old woman. Her breast cancer(pathologically invasive ductal carcinoma)was 42 mm in diameter and located at B area(lower-inner quadrant)with marked skin invasion (cT4bN0M0, Stage ⅢB). Mastectomy with about 10×10 cm skin resection plus sentinel lymph node biopsy was performed in August 2022 after neoadjuvant endocrine therapy(anastrozole). The skin defect after mastectomy was reconstructed with the rhomboid flap designed at D area(lower-outer quadrant). Her cutaneous local flap after the operation showed an excellent condition and she was discharged with no wound complications. The rhomboid flap was designed quickly and easily with no special instruments, and resulted in a good cosmetic outcome. Therefore, rhomboid flap reconstruction was a very useful method to cover the skin defect after mastectomy of locally advanced breast cancer.

Three patients with locally advanced sigmoid colon cancer with bladder invasion underwent 8 courses of neoadjuvant chemotherapy to achieve complete resection and bladder preservation. All 3 patients showed tumor shrinkage on abdominal contrast CT, and laparoscopic sigmoid colon resection and partial bladder resection were performed. The therapeutic effects were Grade 3 in 2 cases and Grade 2 in 1 case. All 3 patients received 4 courses of postoperative adjuvant chemotherapy, and none of them had recurrence.

A 93-year-old woman was admitted to another hospital because of pain during defecation at the colostomy, and was referred to our hospital because of a mass at the colostomy. She had undergone abdominoperineal resection for rectal cancer 18 years ago. A hard mass with poor mobility was palpable at the tip of the colostomy with a third-quarter circumference, and the outlet of the colostomy was stenosed. Biopsy of the mass revealed adenocarcinoma and we made a diagnosis as colostomy cancer. We decided to perform radical surgery, because it was suggested to be Stage Ⅱ disease. A circumferential skin incision was made 5 mm away from the colostomy. The colon used for the colostomy was separated from the extraperitoneal route, and the colostomy intestine tract was cut at 5 cm oral side from the tumor. Lymph node dissection was performed in D1 area. The neo-colostomy was reconstructed at the same site as before the surgery. The histopathological examination revealed moderately differentiated adenocarcinoma, pT3N0M0, pStage Ⅱa(JCCRC 9th edition). After discharge, she has been surveyed regularly without adjuvant chemotherapy.

The patient is a 63-year-old woman who presented to our hospital with anorexia. A CT scan revealed a lead pipe-like structure extending from the cecum, characterized by wall thickening and a villous appearance. Initially suspecting appendicitis with abscess, she was managed with interval appendectomy and antimicrobial therapy. However, with minimal abdominal pain and considering the possibility of appendiceal cancer, colonoscopy was performed on the 8th day of admission, revealing a protruding lesion compressing the appendiceal orifice. Pathological examination confirmed adenocarcinoma, leading to the diagnosis of appendiceal cancer. On the 16th day of hospitalization, she underwent laparoscopic ileocecal resection with D3 lymph node dissection. The final diagnosis was appendiceal mucinous carcinoma, T1, N1a, M0, Stage ⅢA. She received 10 courses of postoperative adjuvant chemotherapy with mFOLFOX6 and has remained recurrence-free for 29 months post-surgery. The preoperative diagnosis of primary appendiceal cancer is challenging. Appendicitis with nonspecific physical findings should raise suspicion of appendiceal cancer as a complication.

We report a case of gallbladder carcinosarcoma in which surgery was performed based on the preoperative diagnosis of acute cholecystitis accompanied by biliary tract bleeding. The patient was an 84-year-old man who came to the emergency department complaining of abdominal pain. Upon close examination, he was diagnosed with acute hemorrhagic cholecystitis and underwent open cholecystectomy. A fresh specimen showed a nodular tumor protruding into the gallbladder lumen. Histopathological examination revealed a mixture of tubular to solid adenocarcinoma, areas showing sarcomatous changes, and findings consistent with chondrosarcoma or osteosarcoma, leading to the diagnosis of gallbladder carcinosarcoma. Although additional resection was not performed due to advanced age and other reasons, recurrence was observed on CT scan 3 months after surgery, and he is currently undergoing chemotherapy. Gallbladder carcinosarcoma is a rare tumor that is a combination of carcinoma of epithelial origin and sarcoma of non-epithelial origin. Even after resection, recurrence is common and the prognosis is poor.

Clinical trials such as the Z0011 trial have shown that axillary lymph node dissection(Ax)can be omitted even in patients with sentinel node(SN)macrometastasis. The 2022 edition of the Japanese guidelines for breast cancer treatment only weakly recommends omitting Ax in cases of SN macrometastasis, and we examined whether Ax could be omitted in 46 Japanese patients in our hospital. The average age of the patients was 60 years, the average tumor diameter was 2.2 cm, 90% were of the luminal type, the average number of SNs sampled was 3.2, and the average number of SN metastases was 1.4. At an average follow-up of 1,672 days, there were 2 cases of distant recurrence, 1 death due to cancer of other organs, and 2 cases of contralateral breast cancer development. There was no axillary lymph node recurrence nor any case where lymphedema developed. Thus, Ax can be safely omitted in Japanese patients with SN macrometastasis under certain conditions.

A 67-year-old woman underwent emergency sigmoid resection for perforated sigmoid cancer with synchronous liver metastasis(pT4aN0M1a, pStage Ⅳa). The patient was administered 7 courses of SOX plus bevacizumab and 7 courses of FOLFIRI plus bevacizumab as adjuvant chemotherapy. Fourteen months post-surgery, PET-CT and EOB-MRI revealed a nodule in segment 8 of the liver. Based on the diagnosis of hepatic metastasis, a partial hepatectomy was performed. Two months after hepatectomy, a recurrent lesion was observed in segment 4 of the liver, and radiofrequency ablation(RFA)was performed. Nine months after RFA, chest CT revealed a solitary nodule in segment 9 of the left lung. Six months later, the size of the pulmonary nodule had increased. A diagnosis of pulmonary metastasis was established, and thoracoscopic partial pulmonary resection was performed. Histopathological examination of the hepatic and pulmonary resection confirmed metastasis from sigmoid cancer. The patient has remained recurrence-free for 5 years following the final surgery. Herein, we report a case of long-term survival in a patient with perforated sigmoid cancer and simultaneous liver metastasis after multidisciplinary treatment.

A 46-year-old woman experienced bleeding from a large tumor in her right breast and was hospitalized after calling an ambulance. At first, we suspected breast cancer, but a core needle biopsy under ultrasound revealed a diagnosis of malignant phyllodes tumor. The bleeding was temporarily controlled using Mohs paste, so emergency surgery was not required. After mastectomy, skin grafting was not needed. Postoperative adjuvant therapy was not planned. 12 months after surgery, recurrence was detected in the lower lobe of the left lung, and we performed a laparoscopic-assisted left lower lobe lung resection. Future recurrences will be managed with chemotherapy and radiation therapy according to sarcoma treatment protocols, and surgery will be considered for operable sites.

Metastasis to axillary lymph nodes from gastrointestinal malignancies is rare and has been infrequently reported. We report a case of rectal cancer with metastasis to the left axillary lymph nodes. The patient was a 61-year-old woman who visited her local doctor with the chief complaint of abdominal pain. She was prescribed laxatives; however, there was no improvement and she presented to our emergency department for vomiting. Contrast-enhanced CT of the abdomen showed irregular wall thickening of the rectal Rs with contrast enhancement and dilation of the mouth side of the intestine. Multiple large lymph nodes were also observed near the lesion, around the inferior mesenteric artery, and in the para-aortic region. This suggests multiple lymph node metastases from rectal cancer. In addition, a calcified nodule was observed on the dorsal surface of the uterus, along with an ascites effusion, leading to the suspicion of a disseminated nodule. The patient underwent urgent colonic stenting for bowel obstruction due to rectal cancer. Although the patient was being considered standby for rectal cancer resection followed by chemotherapy, preoperative chest CT showed multiple enlarged lymph nodes in the left axilla, left pectoral interstitium, subpectoralis minor, and left supraclavicular fossa, as well as a mass lesion in the left mammary CD region, leading to the suspicion of breast cancer with lymph node metastasis. Fine-needle aspiration cytology of the axillary lymph nodes was consistent with a Class Ⅴ breast cancer origin, but core needle biopsy of the mass lesion in the left mammary gland showed no evidence of malignancy. Therefore, axillary lymph node metastasis was considered to originate from negative breast cancer or unknown primary or rectal cancer. Laparoscopic low anterior resection, D2 dissection, and biopsy of the left axillary lymph node were performed for rectal cancer obstruction and Stage Ⅳ. Pathological results showed that the morphology of the adenocarcinoma in the left axillary lymph node was similar to that of the colorectal cancer lesion, and immunostaining results were consistent with lymph node metastasis in colorectal cancer. Based on the above, a diagnosis of rectal cancer Rs with left axillary lymph node metastasis(pStage Ⅳ)was made, and postoperative chemotherapy was started from the 5th week. Chemotherapy is currently ongoing 6 months after surgery.

A 50-year-old male was diagnosed with a submucosal tumor of the ampulla of Vater, as determined by esophagogastroduodenoscopy 9 months before surgery. EUS revealed that the submucosal tumor had invaded the sphincter of Oddi surrounding the ampulla of Vater, and tumor biopsy revealed neuroendocrine tumor(NET)Grade 1(G1). As contrast-enhanced computed tomography showed no obvious lymph node or distant metastasis, a subtotal stomach-preserving pancreaticoduodenectomy with lymph node dissection was performed. Microscopic examination of the resected 1.8×1.5 cm tumor showed that eosinophilic and oval atypical cells with tubular or alveolar structures, which tested positive for synaptophysin, chromogranin A, and CD56 on immunohistochemistry, invaded the sphincter of Oddi of Vater papilla. The Ki-67 labeling index was <1%, and lymph node metastases were detected, with a diagnosis of NET G1, pT2N1M0. Because NET of the ampulla of Vater tends to spread to the lymph nodes, radical resection with lymph node dissection is recommended. However, the indications for endoscopic or papillary local resection of small NETs(<2 cm)of the ampulla of Vater are controversial. We report a rare preoperative diagnosis and resected case of NET of the ampulla of Vater, along with the findings of previous studies.