The patient was a 72-year-old woman who had previously undergone pylorus-preserving pancreaticoduodenectomy for pancreatic ductal adenocarcinoma(PDAC), followed by 1 year of adjuvant chemotherapy with S-1. Forty-eight months after surgery, imaging revealed a solitary tumor in liver S6. PET-CT showed no other metastatic sites, and liver biopsy confirmed adenocarcinoma consistent with pancreatic origin, leading to the diagnosis of metachronous liver metastasis. An extended subsegmentectomy of S6 was performed, and pathology revealed liver metastasis with infiltration into the right hepatic vein but negative surgical margins(R0). Postoperatively, the patient received an additional year of S-1 chemotherapy. At 2 years after hepatectomy, the patient remains recurrence-free under regular outpatient follow-up. Although current PDAC guidelines do not recommend liver resection for metastatic disease due to its typically poor prognosis, recent case reports suggest that surgical intervention may benefit selected patients with solitary liver metastases and a long disease-free interval. This case highlights the potential role of liver resection in carefully chosen patients with oligo-recurrence after PDAC surgery. Accumulation of similar cases and further evaluation of long-term outcomes are necessary to better establish treatment strategies for metachronous liver metastases in PDAC.

A woman in her 70s was diagnosed with borderline resectable pancreatic body cancer(cT3N0M0, Stage ⅢA)in 2014, with invasion of the celiac and splenic arteries. She received chemoradiotherapy(gemcitabine and 50.4 Gy radiotherapy), resulting in tumor shrinkage and decreased tumor markers. Distal pancreatectomy with celiac axis resection(DP-CAR)was performed in July 2015. Pathology confirmed pT3N1M0, Stage ⅢB pancreatic ductal adenocarcinoma. She received adjuvant S-1 therapy postoperatively. In April 2018, local retroperitoneal recurrence was detected, and modified FOLFIRINOX therapy was initiated. After 24 courses, S-1 was added, maintaining stable disease. Chemotherapy was discontinued in April 2020. In June 2023, PET-CT revealed FDG uptake near the right common iliac artery, diagnosed as para-aortic lymph node recurrence. She received radiotherapy(60 Gy/30 fr)combined with gemcitabine and S-1(GS therapy, 8 courses), resulting in tumor shrinkage. Due to isolated recurrence, laparoscopic lymphadenectomy with inferior vena cava resection was performed in January 2024. Histopathology was consistent with metastatic pancreatic adenocarcinoma. She remains recurrence-free and alive.

A male in his 60s who presented for evaluation of markedly elevated serum CA19-9 levels. Imaging studies revealed a carcinoma located in the pancreatic tail. He was diagnosed with resectable pancreatic tail cancer(Pt, TS2[35 mm], T3, S1, RP1, PV1[PVsp], A1[Asp], PL0, OO1[gastric invasion], N0, M0 cStage ⅡA). Neoadjuvant chemotherapy with gemcitabine +S-1 was administered, resulting in a partial response according to RECIST criteria. The patient subsequently underwent distal pancreatectomy, local gastrectomy, and partial left adrenalectomy. Histopathological examination confirmed pancreatic tail carcinoma:Pt, well-differentiated, TS2(30 mm), ypT3, ypS1, ypRP1, ypPV0, ypA0, ypPL1(PLspa), ypOO1(gastric invasion), ypN1a, M0, ypStage ⅡB, R0 resection, Grade 1b. Notably, there was no evidence of direct adrenal invasion. Postoperative adjuvant chemotherapy with S-1 was administered. One year after surgery, contrast-enhanced CT and PET-CT revealed enlargement of the left adrenal gland with abnormal FDG uptake(SUVmax 6.5). EUS-FNA confirmed adrenal metastasis from pancreatic cancer. The patient underwent chemoradiotherapy consisting of 60 Gy in 30 fractions combined with gemcitabine+nab-paclitaxel. Serum CA19-9 normalized, and FDG uptake on PET-CT resolved. Subsequently, a left adrenalectomy was performed. Histopathological evaluation revealed no viable cancer cells, showing only post-treatment changes, consistent with a pathological complete response(Grade 4). The postoperative course was uneventful, and at 6 months post-adrenalectomy, the patient remains recurrence-free without further adjuvant therapy.

Colostomy site carcinoma is an extremely rare clinical entity, particularly as a form of postoperative recurrence. We report a case of recurrent adenocarcinoma at the colostomy site following surgery for rectosigmoid cancer. A male patient in his 70s initially underwent laparoscopic Hartmann's procedure, which was converted to open surgery due to tumor size. While receiving adjuvant CAPOX chemotherapy, a granuloma-like mass at the colostomy site gradually enlarged. Initially considered an inflammatory change, conservative treatment was given;however, due to continuous growth, biopsy was performed and confirmed adenocarcinoma. Given the risk of bowel obstruction from the tumor, resection of the colostomy site along with reconstruction of a new stoma was undertaken. Histopathological findings revealed well-differentiated adenocarcinoma. Postoperatively, the patient resumed systemic chemotherapy with bevacizumab plus FOLFIRI. This case highlights the clinical importance of considering malignant recurrence even when stoma-associated lesions initially resemble benign granulation. Early diagnosis and appropriate surgical intervention are essential for optimal outcomes. We present this case to emphasize the need for vigilant long-term stoma surveillance and rapid diagnostic action in the presence of suspicious lesions.

A 76-year-old man underwent laparoscopic total gastrectomy for advanced proximal gastric cancer and was diagnosed as pT4aN2M0, pStage ⅢA. Three years postoperatively, abdominal CT revealed a 2-cm mass near the splenic hilum, and further evaluation led to a diagnosis of isolated lymph node recurrence of gastric cancer at the splenic hilum. A total of 11 courses of chemotherapy, including nivolumab combined with SOX regimen, were administered. The lesion remained localized with no new metastases, and surgical resection was planned. Robotic distal pancreatectomy was performed using the da VinciTM SP System. The postoperative course was uneventful, and the patient was discharged on postoperative day 10. Pathological examination confirmed metastatic adenocarcinoma. As of 4 months after surgery, the patient remains recurrence-free. We present this resected oligometastasis case with a review of the relevant literature.

Solid papillary carcinoma(SPC)is a newly recognized disease entity that was incorporated into the WHO classification in 2012. It is rare and less than 1% of all breast cancers, that is the reason of no stand treatment protocol. Here, we report a case of SPC encountered at our institution. The patient was a 47-year-old woman who presented with a progressively enlarging mass in the right breast. The tumor was detected as a solid mass with well-defined margins, approximately 5 cm in maximum diameter on imaging examination. Although neoadjuvant chemotherapy was considered due to the large tumor size, no definitive evidence of invasion was found on preoperative evaluation, and upfront surgery was selected. She underwent right total mastectomy and sentinel lymph node biopsy. Histopathological examination revealed solid cellular proliferation with fibrovascular cores, large nest formation, partial comedo necrosis, and a 2 mm focus of invasion, leading to a diagnosis of SPC with invasion. Immunohistochemical staining of the invasive component showed ER-positive, PgR-positive, HER2 score 2+(DISH non-amplified), Ki-67 index 6%, and synaptophysin-positive, suggesting a Luminal-type SPC with invasion. Postoperatively, the patient was started on tamoxifen, and she remains recurrence-free to date. This case underscoring the importance of careful pre-treatment assessment of malignancy.

A 55-year-old man was admitted to our hospital with severe anemia. The cause of anemia was hemorrhage due to the duodenal invasion of pancreatic cancer. Endoscopic hemostasis was not applicable and effect of transarterial catheter embolization was temporary. Emergency surgery was chosen as the only alternative. The tumor directly invaded the mesenterium of the transverse colon and the superior mesenteric vein(SMV)widely. Pancreaticoduodenectomy, right hemicolectomy, and resection of the SMV were performed. Concerning the both resected margins, the hepatic side was simply closed without reconstruction and the caudal side was anastomosed to the left renal vein. In the perioperative period, a diffuse bleeding occurred in the site of gastrojejunostomy and endoscopic hemostasis was done successfully. There were no complications related to modification of the SMV perfusion. The patient was discharged at the 19th postoperative day. Regardless of administration of gemcitabine as adjuvant chemotherapy, he died of developing cancerous peritonitis 3 months after the surgery. Through this experience, we would like to evaluate the significance of multidisciplinary therapy including surgery for hemorrhage due to pancreatic cancer.

We examined the treatment outcomes of brain metastases from gastric cancer in our department.

The patient was a male in his twenties. During the physical examination, a 40-mm mass was palpated in the right lobe of the thyroid gland. Ultrasonography revealed a 42-mm hypoechoic mass with a heterogeneous internal echotexture and a peripheral hypoechoic rim with abundant vascularity in the right thyroid lobe. The CT and MRI findings were a benign mass. Laboratory test results, including thyroid function test results, were within normal limits. Fine-needle aspiration cytology suggested the presence of a follicular neoplasm. Right lobectomy was performed. The pathological diagnosis was encapsulated follicular carcinoma with vascular invasion: pT3a, pNx, pEX0, vascular invasion(positive, multiple), stage Ⅰ, and a high risk of recurrence. The incidence of thyroid cancer is 1.4-2.3 per 100,000 for males and 6.5-10.7 per 100,000 for females in their twenties. Currently, there are no established guidelines for cervical palpation during medical checkups, and physical examinations are performed at the physician's discretion. In this case, the patient could have been cured with local therapy alone if neck palpation had been performed during an earlier examination. The malignancy rate of palpable thyroid nodules is approximately 10%. Cervical palpation remains a valuable screening tool owing to its simplicity and noninvasiveness.

We report a case of pleomorphic invasive lobular carcinoma that developed after surgery for multiple ipsilateral cancers. The patient was a 54-year-old woman who visited our hospital after a tumor-like lesion was noted in her right breast. A needle biopsy revealed that the patient had invasive ductal carcinoma. No obvious distant metastasis was found;therefore, circular mastectomy and axillary lymph node dissection were performed. Histopathological examination revealed the following tumors;Tumor 1:Invasive ductal carcinoma(solid type), tumor diameter 33 mm, ER negative, PgR negative, HER2 negative, Ki-67 20.4%;and Tumor 2:Invasive lobular carcinoma, tumor diameter 6 mm, ER negative, PgR negative, HER2 negative, Ki-67 30.2%. The resection margin was negative, and lymph node metastasis was diagnosed as 3/12. Postoperative chemotherapy, radiation therapy, and endocrine therapy were performed. One year and 6 months after surgery, a hard lump was found in the remaining breast, and a needle biopsy confirmed it as pleomorphic lobular carcinoma. A pectoral muscle- sparing mastectomy was performed. Pathological examination of the excised specimen revealed new breast cancer:a pleomorphic lobular carcinoma, with tumor diameter 22 mm, and multiple daughter nodules. The resection margins were negative. The results were ER negative, PgR positive, HER2 negative, and Ki-67 25%. As the prognosis and treatment of invasive lobular carcinoma was unclear, caution was required.

Primary squamous cell carcinoma of the small intestine is extremely rare, particularly in patients without adenocarcinoma components. Here, we report a case of a patient with primary small intestinal squamous cell carcinoma along with a brief literature review. The patient was a 70-year-old woman who was referred to our hospital after undergoing lower gastrointestinal endoscopy at another institution for abdominal pain and anemia, which revealed a suspected perforation of a sigmoid colon tumor. Computed tomography revealed a tumor that involved the sigmoid colon, small intestine, and left adnexa, as well as a para-aortic lymph node metastasis that infiltrated the left renal vein. A tumor marker analysis showed elevated SCC antigen levels, endoscopic examination revealed findings suggestive of infiltration from other organs into the sigmoid colon, and a biopsy confirmed squamous cell carcinoma. No findings suggestive of primary squamous cell carcinoma were identified during the systemic examination. Palliative exploratory laparotomy with tumor resection(partial small bowel, sigmoid colon, and left adnexal resection)was performed. The pathological diagnosis was consistent with primary small intestinal squamous cell carcinoma with no adenocarcinoma components detected. Chemotherapy was proposed to improve the patient's prognosis, but the patient opted for best supportive care and died of the primary cancer approximately 6 months after surgery.

Recent advances in chemotherapy for advanced gastric cancer have increased the feasibility of conversion surgery after tumor downstaging. Among these advances, immune checkpoint inhibitors(ICIs)have shown promising results, particularly in MSI-high tumors.

A 75-year-old man presented with epigastric discomfort and weight loss and was diagnosed with unresectable advanced gastric cancer with small bowel and pancreatic invasion(cT4bN3aM0, CY0, P0, cStage ⅣA). He received standard chemotherapy, including 6 courses of S-1/oxaliplatin therapy as the first-line treatment and 2 courses of paclitaxel/ramucirumab therapy as the second-line treatment. Because of the primary tumor growth and appearance of massive ascites, nivolumab monotherapy was introduced as a third-line treatment. After 13 courses of nivolumab, the primary tumor significantly shrank, and the ascites disappeared. The patient underwent distal gastrectomy and D2 lymphadenectomy as conversion surgery. The pathological stage was ypT1aN0M0, CY0, P0, and ypStage ⅠA, and the therapeutic effect was Grade 2b. The patient was alive 42 months postoperatively with no evidence of recurrence. We report a case of a patient with unresectable gastric cancer with peritoneal metastases who underwent conversion surgery after a successful response to nivolumab therapy, with a limited literature review.

A 66-year-old man was referred to our hospital for further evaluation and treatment of advanced gastric cancer, which was diagnosed after the patient presented with a history of a loss of appetite. The patient was diagnosed with advanced gastric cancer with pyloric stenosis and peritoneal dissemination(cT4aN+M1, P1, cStage ⅣB;Japanese Classification of Gastric Carcinoma, 15th edition). After undergoing gastrojejunostomy, the patient received 5 courses of SOX plus nivolumab. The tumor markedly regressed and the peritoneal dissemination disappeared. No peritoneal metastasis(P0)or positive cytology(CY0)was observed on staging laparoscopy, and conversion surgery was deemed feasible. The patient underwent distal gastrectomy with D2 dissection and partial resection of transverse colon to achieve R0 resection. Pathological findings revealed ypT3N2, P0, and CY0, corresponding to ypStage ⅢA. The histological therapeutic effect was graded as Grade 1b. Postoperative adjuvant chemotherapy with oral S-1 was administered for 6 months. The patient remained recurrence-free for 8 months after surgery. Recent research supports that R0 resection through conversion surgery can prolong survival, even in patients with advanced gastric cancer with peritoneal dissemination. Additionally, immune checkpoint inhibitor-based chemotherapy is recommended as first-line treatment for unresectable advanced gastric cancer, with increasing reports of favorable responses. This case is a valuable example in which SOX plus nivolumab therapy was effective, allowing curative resection via conversion surgery in a patient with peritoneal dissemination of advanced gastric cancer.

Gastric adenosquamous cell carcinoma is relatively rare. We report a case of adenosquamous cell carcinoma and a carcinoma producing granulocyte-colony stimulating factor(G-CSF). An 85-year-old man was admitted to our department in 20XX with complaints of anemia and anorexia. Computed tomograph(y CT)showed a rapidly growing mass within 1 month. Based on gastrointestinal endoscopy and elevated tumor markers, the patient was diagnosed with advanced gastric cancer and underwent distal gastrectomy. A biopsy revealed mixed pathological features of adenocarcinoma and squamous cell carcinoma components, leading to a final diagnosis of gastric adenosquamous cell carcinoma. The patient also had preoperative leukocytosis, which immediately improved after surgery, and the pathology was positive for G-CSF staining, leading to the conclusion of a G-CSF-producing tumor. The patient had recurrence at 5 months postoperatively and a palliative treatment plan was initiated. These findings suggest that adenosquamous carcinoma of the stomach and G-CSF-producing tumors may exhibit aggressive behavior and that they should be considered in the differential diagnosis of unexplained leukocytosis.

Skin metastasis of colorectal cancer is a rare condition. Herein, we report a case of skin metastasis of MSI-high sigmoid colon cancer to the buttocks. A 41-year-old male who was referred to our hospital for anemia, elevated inflammatory response, weight loss, and hematochezia during his general health examination. Computed tomography(CT)revealed a thickening of the sigmoid colon wall, fistula formation between other parts of the sigmoid colon, and enlarged mesenteric lymph nodes. The patient was suspected of having skin metastasis due to a mass being found in the upper abdominal subcutaneous region and the skin of the buttock. The buttock and abdominal wall tumors were subjected to pathological examination, which revealed adenocarcinoma. The patient was diagnosed with sigmoid colon cancer with skin metastases. The patient developed an intestinal obstruction during the examination and underwent a transverse colostomy. Subsequently, pembrolizumab was initiated as the first-line treatment because of the presence of MSI-high and RAS gene mutations (G12S mutation). CT taken after the fifth course of treatment indicated that the tumor had shrunk.

Case 1:A 69-year-old man. He was diagnosed with abscess-forming appendicitis and initially managed conservatively, followed by a laparoscopic appendectomy. Histopathological examination revealed goblet cell adenocarcinoma(GCA)of the appendix. A subsequent laparoscopic-assisted ileocecal resection with D3 lymph node dissection was performed. The pathological findings were V, pT3(subserosa), GCA, INF b, BD2, Ly0, V0, Pn1a, pN0, cM0, pPM0, pDM0, pRM0, and pStage ⅡA. Case 2:A 29-year-old man. He underwent a laparoscopic appendectomy for a diagnosis of acute appendicitis. Histopathological analysis revealed GCA of the appendix. A laparoscopic-assisted ileocecal resection with D3 lymph node dissection was subsequently performed. The pathological findings were V, pT3(subserosa), GCA, INF c, BD1, Ly0, V0, Pn0, pN0, cM0, pPM0, pDM0, pRM0, and pStage ⅡA. These cases are reported with a review of the relevant literature.

A 66-year-old woman was referred to our hospital with complaints of pain in the lower right abdomen and bloody stools for 2 days. The WBC counts of 9,100/μL, CRP levels of 5.0 mg/dL, Hb counts of 9.8 g/dL were without normal range, but no other abnormal values were noted. Abdominal CT showed intussusception of the right colon with a solid tumor. Lower gastrointestinal endoscopy revealed a type 1 tumor in the ascending colon. The scope was not passed through to the oral side, and repositioning by endoscopy was unsuccessful. Since abdominal pain had been continued, an emergency surgery was performed. Surgical findings revealed a protruding lesion at the ascending colon that extended to the transverse colon, and the intussusception was intrusive up to the ascending colon at the end of the intestinal ileum. Thus, right hemicolectomy of the colon with D3 lymphadenectomy was performed. Resected specimens revealed a type 1 tumor measuring 60 mm in diameter at the ascending colon. Histopathologic findings revealed pT2, pN1a, cM0, pStage Ⅲa tumor. The postoperative course was favorable, and the patient was discharged on the postoperative day 13.

A 58-year-old male patient underwent laparoscopic-assisted high anterior resection and D3 dissection for sigmoid colon cancer in April 2017. Pathology results showed S, type 2, tub1, pSS, pN1, ly1, v0, pStage Ⅲa. He was treated with S-1 for 6 months as adjuvant chemotherapy. One year after surgery, PET-CT showed a peritoneal seeding nodule localized in the pelvis, and he underwent laparoscopic partial omentectomy and partial resection of the small intestine. Subsequently, a total of 35 courses of FOLFOX+Pmab therapy were performed. During this period, there was no apparent recurrence on imaging, but skin disorder appeared. So he was switched to S-1. During this period, CEA showed a gradual increase, and a PET-CT in February 2022 showed a single peritoneal seeding recurrence in the pelvis, and a laparoscopic resection of the tumor was performed in March of the same year. After the surgery, he underwent another 7 courses of S-1 at his strong wish. In October of the same year, PET-CT showed multiple peritoneal seeding nodules, and he underwent a total of 7 courses of FOLFOX+Pmab therapy. In June 2023, the skin disorder worsened again, and he was switched to FOLFIRI and received 1 course. However, at the patient's strong wish, he underwent immunotherapy and radiotherapy at another hospital. In October of the same year, he came back to our hospital and started FTD/TPI+Bmab because of increased CEA and increased peritoneal nodules. Although his CEA was gradually decreasing, he underwent laparoscopic small bowel bypass surgery in October 2024 due to the appearance of intestinal obstruction caused by peritoneal seeding nodules after 10 courses of FTD/TPI+Bmab. After the surgery, FTD/TPI+Bmab was resumed. He is now in a state of stable disease 8 years after the initial surgery(7 years after the recurrence of peritoneal dissemination).

We report a rare case of subcutaneous local recurrence of cecal cancer with subcutaneous abscess formation, successfully managed by additional resection. An 86-year-old woman underwent ileocecal resection with partial peritoneal resection for cecal adenocarcinoma complicated by a subcutaneous abscess. Postoperative chemotherapy was administered, and the patient was followed up regularly. Five months later, a painful subcutaneous mass appeared in the right lower quadrant. Imaging studies, including CT and PET-CT, indicated subcutaneous local recurrence. Surgical excision was performed due to symptom progression. Histopathological and immunohistochemical findings confirmed recurrent adenocarcinoma of cecal origin. The patient has remained recurrence-free for 17 months.