A 66-year-old man with acute myeloid leukemia with myelodysplasia-related changes (AML-MR) was admitted in April 2024 after presenting with increased peripheral blood blasts. At the initial visit, he had atrial fibrillation but no pericardial effusion. Although treatment with venetoclax and azacitidine reduced peripheral blood blasts, a concurrent cardiac tamponade was observed in May of the same year. Pericardial drainage was performed, and cytology and flow cytometry of the pericardial fluid confirmed a diagnosis of pericardial infiltration due to AML. Pericardial effusion resolved with repeated intrapericardial injections of cytarabine, allowing discontinuation of pericardial drainage. Remission induction therapy with daunorubicin and cytarabine was subsequently administered. Palliative care for AML was given during the cardiac treatment, and pericardial effusion did not occur prior to the patient's death in February 2025.

An 87-year-old man was diagnosed with diffuse large B-cell lymphoma in 2020. The disease relapsed repeatedly and remained poorly controlled despite multiple salvage chemotherapy regimens. In February 2024, inguinal lymphadenopathy reappeared and epcoritamab was administered as the sixth line of chemotherapy. Tumor area assessment showed transient increases on days 4, 12, and 17. Macroscopic redness and elevation were also observed. This was considered a tumor flare reaction because it disappeared transiently. We report this case as an example of successful serial imaging of lesions from the start of epcoritamab therapy to visually confirm changes that may constitute a tumor flare reaction.

Case 1: Urgent examination of a 72‒year‒old man with hematemesis revealed a gastroesophageal tumor. Biopsy revealed gastric cancer, and computed tomography(CT)revealed enlarged lymph nodes and multiple liver metastases. Laparoscopic gastrectomy led to the diagnosis of a pT3N2M1(HEP), pStage Ⅳ liver tumor. A CT scan performed 2 months postoperatively revealed enlargement of the liver tumor, suggesting hepatocellular carcinoma and prompting right liver lobectomy. Histopathological examination of the operative specimen revealed metastatic hepatocellular carcinoma. Adjuvant chemotherapy(S‒1)was administered postoperatively but was discontinued because of severe adverse effects. To date, the patient has been recurrence‒free for 3 years. Case 2: A 79‒year‒old man with black stools who had not sought treatment presented to the emergency department with nausea and dizziness. A CT scan revealed a gastric mass, enlarged lymph nodes, and a liver tumor. After a thorough investigation, gastric cancer(cT4aN2M1[HEP], cStage ⅣB)was diagnosed. As the liver metastasis was solitary, pylorus‒preserving gastrectomy and partial hepatic resection were performed. Adjuvant chemotherapy(S‒1)was administered for 1 year, during which the patient remained recurrence‒free. Given that resection of liver metastases from gastric cancer often achieves long‒term survival, we performed this procedure as a component of multidisciplinary treatment.

A 52‒year‒old female with gastric cancer revealed by a medical examination. The patient was diagnosed with T4b(pancreas)N2M0, CY0P0, cStage ⅣA, and after 3 courses of docetaxel+oxaliplatin+S‒1(DOS)therapy as preoperative chemotherapy, laparoscopic distal gastrectomy with D2 lymph node dissection and Roux‒en‒Y reconstruction were performed. Pathological histological examination showed ypT3(SS)N2M1(CY+), Stage Ⅳ, HER2(-), and S‒1+oxaliplatin(SOX)therapy was initiated as first‒line treatment. Tumor markers elevated and CT scan showed ascites after 5 courses and the treatment was consequently changed to paclitaxel+ramucirumab(PTX+Ram)therapy as second‒line treatment. CT scan showed para‒aortic lymph node enlarged and increased ascites after 2 courses, MSI‒High was identified at the same time and the treatment was consequently changed to pembrolizumab(Pem)monotherapy(200 mg/body, q21 days)as third‒line treatment. CT scan showed partial response(PR)after 3 courses, and subsequently resulted in a complete response(CR). After 36 courses of Pem monotherapy, the chemotherapy was terminated at the patient's request. Four years after the initial onset, the patient is currently alive without recurrence. No serious adverse events have occurred since the start of Pem monotherapy.

The patient was a 53‒year‒old man who presented to our hospital for evaluation of epigastric pain. Gastroscopy revealed a submucosal tumor with delle. Biopsy specimens showed spindle cell proliferation in a palisading pattern, and immunohistochemical staining(IHC)was positive for c‒kit, leading to a diagnosis of GIST. We underwent surgical resection after NAC and achieved a complete resection. The histopathological findings from the resected specimen differed markedly from the biopsy specimen, making the postoperative diagnosis difficult. There have been few reports on the IHC change in cases of GIST after NAC, so we report this case and provide a literature review.

A 49‒year‒old woman presented to our hospital with right lower abdominal pain that had been presenting for about 6 days without any improvement. An abdominal CT examination demonstrated an enlarged appendix and stercolith of appendix with inflamed surrounding adipose tissue. Antibiotic treatment was administered, but an abdominal CT examination taken 3 days later showed worsening inflammation around the appendix. An appendectomy was laparoscopically performed. Upon resection, the enlarged appendix was found. In immunohistochemical staining, the resected tissue was positive for neuroendocrine markers, including chromogranin A, synaptophysin, Ki‒67, and a definitive diagnosis of neuroendocrine tumor(NET)G1 was obtained. The patient has been followed up without additional resection or adjuvant chemotherapy, and no recurrence has been observed. Appendix NETs are often diagnosed incidentally, as in this case. In treating appendicitis, it is essential to perform pathological examination of the resected specimen.

A 74‒year‒old man was diagnosed with cecal cancer and performed ileo‒cecal resection with D3 lymphadenectomy. The postoperative pathological diagnosis was pT3N0M0, pStage Ⅱa. He was followed up without postoperative adjuvant chemotherapy. One year after the surgery, he developed pain in the port area of the right‒lower abdomen, and CT showed a mass with contrast enhancement at the port site. In addition, a lymph node mass was observed in the right inguinal region. Because of severe pain at the port site, an excisional biopsy of the abdominal wall was performed for both diagnostic and therapeutic purposes. The pathological diagnosis confirmed metastasis of cecal cancer. An excisional biopsy of a lymph node in the right inguinal region was performed, and pathological diagnosis was a metastasis of cecal cancer. Two years have passed without postoperative chemotherapy, and he remains alive without recurrence. The metastasis was thought to have metastasized lymphatically to the inguinal region from the port site recurrence. We report on the port site recurrence and lymphatic metastasis from the metastatic lesion.

A 75‒year‒old man consulted our hospital with abdominal pain and fever. He was diagnosed as abscess‒forming appendicitis by contrast‒enhanced computed tomography(CT), and underwent conservative treatment and CT‒guided drainage. CT‒guided drainage revealed no abscess. Follow‒up contrast‒enhanced CT and MRI revealed a diagnosis of appendiceal mucinous neoplasm and peritoneal pseudomyxoma. Hence, the treatment strategy was operation. Intraoperative findings revealed mucus deposits in the right paracolic gutter and around the liver. The mucus was examined cytologically, but no malignant findings were detected. An ileocecal resection was performed. The pathological diagnosis was high‒grade appendiceal mucinous neoplasm(HAMN). The patient was discharged without postoperative complications. The patient was alive and recurrence‒free, 12 months after surgery. We report this rare case with a review of the literature.

A 74‒year‒old male was diagnosed with advanced rectal cancer with bowel obstruction, and abscess formation. After sigmoid colostomy, FOLFOXIRI plus bevacizumab as preoperative chemotherapy was initiated. On day 3, during continuous administration of 5‒fluorouracil(5‒FU), the patient developed impaired consciousness accompanied by convulsive seizures and conjugate deviation. Electroencephalography(EEG)revealed no epileptic discharges, and imaging studies revealed no abnormality. A blood test showed a high ammonia level of 367μmol/L. In the absence of prior liver disease, the cause was suspected to be due to high‒dose 5‒FU. Administration of lactulose was started. The ammonia level normalized and the consciousness recovered quickly by the following day. It was thought that chemotherapy would be difficult to continue, and 1 month later, robot‒assisted low anterior resection and ileostomy were performed. The patient was discharged home without complication on postoperative day 13. We report this case of advanced rectal cancer in which administration of high‒dose 5‒FU caused hyperammonemia accompanied by impaired consciousness, with a literature review.

The patient was a 78‒year‒old woman. A liver tumor was detected on abdominal computed tomography(CT)performed for follow‒up after breast cancer surgery. Further examination revealed transverse colon cancer and liver metastases; therefore, transverse colon resection with D3 lymph node dissection and resection of the central 2 segments of the liver were performed. Four months later, liver recurrence was found on CT, which was diagnosed as unresectable, and chemotherapy was planned. Chemotherapy with capecitabine+oxaliplatin+bevacizumab was initiated. The capecitabine and oxaliplatin dosages were reduced due to adverse events. The CT scan showed PR; therefore, maintenance therapy with capecitabine+bevacizumab was initiated. The recurrent tumor continued to gradually shrink, and only a cystic lesion was observed on CT. CT performed 4 years and 1 month after the initiation of chemotherapy showed that the cystic lesion had almost disappeared from the liver. We believe that the factor contributing to the long‒term response in this case was the appropriate dose reduction and cessation of chemotherapy.

An 88‒year‒old woman visited the gynecology department of our hospital with a chief complaint of frequent urination and abdominal mass. Contrast‒enhanced CT and MRI scans of the abdomen revealed an 8 cm‒sized irregularly shaped mass in widely contact with sigmoid colon and perforated to the bladder. Colonoscopy could not reach the tumor because of huge mass. The diagnosis was resectable pelvic tumor without distant metastasis, and surgery was performed. The tumor was resected en bloc with sigmoidectomy, hysterectomy and partial cystectomy. The majority of the tumor was in the bladder lumen and appeared to be of bladder origin, but final histopathology led to a diagnosis of mucous carcinoma from a diverticulum in the sigmoid colon. Eighteen months after surgery, the patient is alive without recurrence.

Chronic inflammatory conditions, such as obstructive colitis and inflammatory bowel disease(IBD), are representative causes of colonic fibrosis. In addition, there have been reports that endoscopic interventions, including biopsies and local therapies, may induce submucosal fibrosis.

A 72‒year‒old man was referred to our hospital with a chief complaint of abdominal pain. Computed tomography(CT)revealed a tumor approximately 17 mm in diameter in segment 7(S7)of the liver. The tumor demonstrated ring enhancement and was associated with vascular invasion(Vp2). He was diagnosed with intrahepatic cholangiocarcinoma and underwent a laparoscopic posterior segmentectomy. Intraoperative findings revealed the tumor as a hard white mass on the surface of the liver. The patient was discharged on postoperative day 9. Histopathological examination revealed a highly sclerotic lesion with extensive hyalinization and fibrosis, leading to a final diagnosis of sclerosed hemangioma. It is generally difficult to distinguish sclerosed hemangiomas from malignant tumors preoperatively. We report this case along with a review of the literature.

Neoadjuvant chemotherapy followed by radical esophagectomy is the standard treatment for advanced esophageal cancer in Japanese treatment guideline. However, in elderly patients with dysphagia and impaired organ function, preoperative chemotherapy may worsen their condition. We report here a case of a 79‒year‒old malnourished man with advanced esophageal squamous cell carcinoma and EGJ adenocarcinoma presenting with severe dysphagia. Given his age, frailty, and high‒risk of systemic decline, initial mediastinoscopic esophagectomy was selected over neoadjuvant therapy. Pathology showed a positive radial margin and PD‒L1 expression, prompting postoperative local salvage radiotherapy(40 Gy/20 fr)with nivolumab(480 mg/4 weeks). After 4 cycles, nivolumab was discontinued due to immune‒related pneumonitis, and S‒1 chemotherapy was initiated. Nearly 2 years postoperatively, the patient remains recurrence‒free. This case demonstrates the feasibility of a personalized, minimally invasive treatment strategy with tailored adjuvant therapy in high‒risk elderly patients.

This case concerns a woman in her 20s with abdominal pain. Abdominal computed tomography revealed a large hepatic tumor with extensive infiltration of both liver lobes. She developed acute liver failure and was immediately admitted to our hospital. Her condition rapidly deteriorated, progressing to multiple organ failure, leaving insufficient time for comprehensive evaluation. She died 4 days after admission. Autopsy showed marked hepatomegaly due to tumor, with the liver weighing 3400g. Pathological diagnosis was combined hepatocellular-cholangiocarcinoma (cHCC-CCA), a rare primary liver cancer. We report an extremely rare case of cHCC-CCA in a young woman without a history of chronic liver disease.

A 25-year-old female patient was referred to our department due to fever and cervical lymphadenopathy. Computed tomography showed bulky mediastinal lesions and bilateral supraclavicular and axillary lymphadenopathies. Cervical lymph node biopsy revealed nodular sclerotic Hodgkin's lymphoma (NS-HL) comprised of large Hodgkin/Reed-Sternberg (HRS) cells with sheet-like aggregates. The patient was diagnosed with a syncytial variant (SV). Immunohistochemical staining of HRS cells was positive for CD30, PD-L1, and MYC and negative for Epstein-Barr virus encoding region (EBER). The patient was assigned clinical stage IIB according to the Lugano classification and the poor prognosis group according to the National Comprehensive Cancer Network (NCCN). Furthermore, treatment with AVD (adriamycin/vinblastine/dacarbazine) in combination with brentuximab vedotin (BV) was initiated to achieve a complete metabolic response. Histopathologically, SV has a high proportion of HRS cells, with high CD30-positive and low EBER-positive rates. Therefore, CD30-targeted therapies such as BV may be preferable for SV, even in localized NS-HL patients, thereby improving patient prognosis.

A 70-year-old man with prostate cancer (cT3aN0M0), with a prostate-specific antigen (PSA) level of 38.9 ng/mL, and a Gleason score of 4+4 = 8, was treated with maximum androgen blockade for 1 year, resulting in a PSA reduction to 0.1 ng/mL. He subsequently underwent robot-assisted laparoscopic radical prostatectomy (RARP). Pathological examination revealed pT3bN1with negative surgical margins. Postoperatively, without additional treatment, PSA levels were 0.007 ng/mL and 0.019 ng/mL at 2 and 5 months, respectively. Six months after surgery, the patient developed left hydronephrosis with upper ureteral urine leakage but no signs of ureteral cancer. However, PSA slightly increased to 0.055 ng/mL, whereas carcinoembryonic antigen (CEA) levels increased to 19.2 ng/mL. Despite this, gastro-colonoscopy failed to detect any evidence of cancer. Nine months after surgery, multiple lung tumors, a solitary hepatic tumor, intraperitoneal lymphatic swellings, and port site masses were identified. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography scan did not reveal any other malignancies. At that time point, PSA increased to 0.185 ng/mL, while neuron-specific enolase and pro-gastrin-releasing peptides levels were within normal limits. Subsequent gastro-colonoscopy did not detect any malignancies. Ten months after surgery, bilateral orchiectomy and docetaxel chemotherapy were initiated for recurrent prostate cancer with aggressive variants but without neuroendocrine differentiation. Immunohistochemistry (IHC) of a biopsy sample from the port site mass suggested enteric adenocarcinoma distinct from the prostatic tissue observed in the original RARP specimen. The metastases progressed, and CEA levels continued to rise despite three cycles of docetaxel chemotherapy. Genomic testing identified KRAS and other mutations, confirming the tumor's compatibility with enteric adenocarcinoma. Fourteen months after surgery, chemotherapy for colon cancer was initiated. Unfortunately, the patient succumbed to respiratory failure 19 months after surgery. In cases of unusual recurrence patterns, as observed in this case, IHC and genomic testing of the recurrent mass can be crucial for accurate diagnosis.

We performed robot-assisted radical prostatectomy (RARP) for 221 patients from December 2015 to May 2023. In 218 patients, the prostatic anterior fat pad was submitted separately for histopathological evaluation. Fourteen patients (6.4%) had lymph nodes in the prostatic anterior fat pad, and three (1.4%) had lymph node metastasis in the prostatic anterior fat pad. The details of three cases are presented here.Case 1 was a 63-year-old patient who underwent RARP for prostate cancer (cT2aN0M0), with an initial prostate-specific antigen (PSA) concentration of 24.522 ng/ml and a Gleason score of 3+4. The pathological results indicated adenocarcinoma, pT3a, Gleason score: 3+4. The postoperative PSA nadir was 0.205 ng/ml, and the patient was diagnosed with biochemical recurrence. Subsequently, the patient underwent hormone therapy and salvage radiation therapy, with no recurrence to date.Case 2 was a 62-year-old patient who underwent RARP for prostate cancer (cT2aN0M0), with an initial PSA of 10.418 ng/ml and a Gleason score of 4+4. The pathological results indicated adenocarcinoma, pT2c, Gleason score: 4+4. The postoperative PSA nadir was 0.401 ng/ml, and the patient was diagnosed with biochemical recurrence. The patient subsequently underwent hormone therapy.Case 3 was a 76-year-old patient who underwent RARP for prostate cancer (cT2aN0M0), with an initial PSA of 4.676 ng/ml and a Gleason score of 4+3. The pathological results indicated adenocarcinoma, pT2c, Gleason score: 3+4. The postoperative PSA nadir was 0.031 ng/ml, and the patient has not experienced recurrence to date.

(Objective) Patient characteristics and treatment outcomes of a rare histologic type of bladder neuroendocrine carcinoma were evaluated. (Methods) 2,133 cases of bladder cancer treated by transurethral resection of bladder tumor from August 2005 to August 2022 were histopathologically reevaluated, and clinicopathological factors, treatment methods, and prognosis of cases with a confirmed diagnosis of bladder neuroendocrine cancer were analyzed. (Results) Of 2,133 cases, 12 (0.56%) were diagnosed as neuroendocrine carcinoma. Immunohistochemical staining revealed small cell carcinoma in 10 cases (83.3%) and large cell carcinoma in 2 cases (16.7%). The median age was 79 years, and performance status 2 or higher was reported in 3 cases. Seven cases had localized cancer at the time of diagnosis, five cases had distant metastasis, and radical cystectomy was performed in four cases. Of the 3 cases who received chemotherapy, first-line platinum-based chemotherapy achieved disease control in two cases. After second-line treatment, no cases responded to pembrolizumab or enfortumab vedotin. The median overall survival (OS) of all cases was 12.5 months. The median OS of cases who underwent total cystectomy was 26 months, and that of cases who did not undergo total cystectomy was 8.2 months, showing a significant difference (p=0.05). (Conclusion) Neuroendocrine carcinoma of the urinary bladder often develops in older patients and has a poor prognosis. In cases of localized cancer, total cystectomy should be performed if possible.

A 62-year-old woman was admitted and underwent endoscopic mucosal resection for sigmoid colon cancer.Histopathological examination revealed submucosal invasion of 3,000 μm with positive tumor budding(Grade 2).Subsequently, she underwent laparoscopic sigmoidectomy with D2 lymphadenectomy.Postoperative pathology showed no regional lymph node metastasis, and the disease was staged as pStage Ⅰ.Chest CT scans revealed small nodules in the right middle lobe and left lower lobe that had been noted preoperatively and demonstrated gradual enlargement.Twenty four months after the initial surgery, these were diagnosed as synchronous pulmonary metastases, and she underwent thoracoscopic partial resections of both lungs.Nonetheless, the patient remains alive, with no recurrence 10 years after the resection of the pulmonary metastases.