[A Case of Breast Metastasis from Renal Cell Carcinoma].

The patient was a woman in her 90s. Right radical nephrectomy for right renal cell carcinoma had been performed 2 years and 6 months ago. Since then, there had been no recurrence. However, computed tomography during postoperative follow- up period showed a 3 cm mass in the right breast, and the patient was referred to our department. Breast ultrasonography indicated a well-circumscribed, oval, and almost smooth-surfaced tumor, 27 mm in size, located in the D region of the right breast. Results of a core needle biopsy showed metastatic renal cell carcinoma and clear cell carcinoma. Preoperative examination confirmed intramammary metastases of renal cell carcinoma. Given that the patient did not experience systemic metastases, partial mastectomy of the right breast was performed. Metastatic renal cell carcinoma is associated with poor prognosis. Generally, standard treatment in this disease is chemotherapy. However, surgical resection is selected with the aim of improving the prognosis and achieving radical cure of patients with this complication if these patients are in an oligometastatic state and complete resection of metastatic lesions is feasible, as in the present case. To achieve radical cure, the patient underwent partial mastectomy under local anesthesia, which is a relatively minimally invasive surgery.

Lynch syndrome-associated chordoma with high tumor mutational burden and significant response to immune checkpoint inhibitors.

Chordoma is a rare malignant bone tumor arising from notochordal tissue. Conventional treatments, such as radical resection and high-dose irradiation, frequently fail to control the tumor, resulting in recurrence and re-growth. In this study, genetic analysis of the tumor in a 72-year-old male patient with refractory conventional chordoma of the skull base revealed a high tumor mutational burden (TMB) and mutations in the MSH6 and MLH1 genes, which are found in Lynch syndrome. The patient and his family had a dense cancer history, and subsequent germline genetic testing revealed Lynch syndrome. This is the first report of a chordoma that has been genetically proven to be Lynch syndrome. Chordomas usually have low TMB; however, this is an unusual case, because the TMB was high, and immune checkpoint inhibitors effectively controlled the tumor. This case provides a basis for determining the indications for immunotherapy of chordoma based on the genetic analysis. Therefore, further extensive genetic analysis in the future will help to stratify the treatment of chordoma.

Four Patterns of Abnormal Ring-Like Uptakes on Dedicated Breast PET.

ABSTRACT: The high resolution of dedicated breast PET (dbPET) enables the visualization of small breast cancers and a heterogeneity of breast tumors. Some tumors present with a ring-like appearance, the central uptake defect possibly reflecting intratumoral fibrosis and necrosis, associated with high-grade malignancy, and a triple-negative subtype. However, a ring-like finding is not only found in high-grade breast cancers. We describe 4 representative patterns of ring-like uptakes on dbPET: high-grade invasive cancer, intracystic tumor, extended noninvasive carcinoma, and change after vacuum-assisted breast biopsy. Ring-like uptakes on dbPET should be evaluated in association with clinical information.

Mixed neuroendocrine-non-neuroendocrine neoplasms of ascending colon: A case report.

INTRODUCTION: Neuroendocrine tumor (NET) that develops in the right-sided colon is relatively rare. Coexistence of adenocarcinoma and NET is extremely rare, and such cases are called mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN). PRESENTATION OF CASE: Colonoscopy in an 85-year-old woman for an anemia examination indicated laterally spreading tumor-nongranular (LST-NG) in the transverse colon. Colonoscopy and endoscopic ultrasonography (EUS) showed that the depth of the tumor invasion was deep submucosal. The tumor localization was diagnosed as transverse colon close to the hepatic curvature by enema. Computed tomography (CT) showed no obvious lymph node or distant metastasis. Based on these findings, laparoscopic transverse colectomy with D2 lymphadenectomy was performed. Pathologically, most of the tumor was well-differentiated tubular adenocarcinoma, but some solid follicles of polygonal tumor cells with poor nuclear atypia were observed. Immunostaining was positive for synaptophysin and diagnosed as NET G1. This tumor consisted of adenocarcinoma and neuroendocrine tumor, so we diagnosed it as MiNEN and classified the tumor as fT1N0M0 fStage I (TNM Classification of Malignant Tumors, 8th Edition). Since it was an early stage cancer, postoperative adjuvant therapy was not performed. No recurrence has yet been noted. DISCUSSION: Although MiNEN is extremely rare, the detailed pathological specimen observation and diagnosis are important because long-term follow-up after surgery is needed, as is the adequate selection of postoperative adjuvant therapy. CONCLUSION: It is important to elucidate the mechanisms involved in the coexistence of NET and adenocarcinoma and to apply these findings to future medical care.

Inguinal bladder hernia treated using transabdominal preperitoneal approach: A case report.

INTRODUCTION: Inguinal bladder hernia (IBH) is a rare condition that is difficult to diagnose preoperatively based only on physical examination; 16% of IBHs are diagnosed postoperatively due to complications. PRESENTATION OF CASE: We report the case of a 56-year-old man who presented with left inguinal swelling and increased frequency of urination since eight years. Physical examination demonstrated a 6 × 4 cm non-reducible left inguinal bulge with mild tenderness on palpation. Computed tomography revealed a left inguinal hernia containing a portion of the urinary bladder. He was diagnosed with IBH and transabdominal preperitoneal (TAPP) repair was performed. We confirmed a left internal inguinal hernia and incised the peritoneum from the outside of the left inguinal ring. The preperitoneal space was dissected toward the Retzius space, and the prolapsed bladder was examined. The adhesion with the surroundings was carefully dissected and the bladder was reduced into the abdomen. Indigo carmine was injected through a urinary catheter, which confirmed that no bladder damage had occurred. After the mesh was positioned to cover the myopectineal orifice, it was fixed to the Cooper's ligaments, interior side, lateral side, and ventral side. The postoperative course was uneventful, and the patient is now free of symptoms and recurrence two months after surgery. CONCLUSION: TAPP repair is a useful treatment for IBH. Preoperative diagnosis of IBH is important to lessen postoperative complications.

Rectal Arteriovenous Malformation Treated by Transcatheter Arterial Embolization.

An 86-year-old man who presented with frequent hematochezia with mild anemia on blood tests was admitted to our hospital. Colonoscopy exhibited a submucosal tumor-like lesion in the lower rectum. CT and MRI showed blood flow into the lesion, but not tumor component. Angiography of the superior rectal artery and left internal iliac artery showed vascular hyperplasia and nidus. Thus, rectal arteriovenous malformation was diagnosed. If bleeding from arteriovenous malformation was out of control, surgical resection was necessary. However, due to the age of the patient, we performed transcatheter arterial embolization and abdominoperineal resection was not needed. Embolization from the left superior rectal artery, middle rectal artery and inferior rectal artery was performed to control the bleeding and to avoid surgery. After embolization, he was followed up for 10 months in our hospital without recurrence.

Large hydrocele of the canal of Nuck diagnosed and treated using conventional and laparoscopic methods.

A 49-year-old woman presented to the hospital with a right inguinal swelling. On examination, we suspected hydrocele of the canal of Nuck (HCN) or an appendiceal or retroperitoneal tumor. Surgery for diagnosis and removal of the mass revealed that it was large and located in the preperitoneal cavity, extending into the inguinal ring; so, it was difficult to observe the entire outline of the mass solely using the laparoscopic approach. Therefore, we added the conventional approach with an inguinal incision. This combination of conventional and laparoscopic approaches helped in safe removal of the tumor. The HCN is an unusual developmental condition in women among whom it might cause an inguinal swelling infrequently. In a case with a large HCN, a combined approach using conventional and laparoscopic methods is suggested for better observation of the abdomen and successful resection without perforation of the mass than when using a single approach.

Multiple peritoneal dissemination of T2 colorectal cancer without lymph node metastases: a case report.

Most cases of peritoneal dissemination of colorectal cancers are from T3 or T4 tumors. A 61-year-old woman was admitted for examination of a positive fecal occult blood test. Colonoscopy showed an ascending colon tumor that was diagnosed as an adenocarcinoma with massive submucosal invasion. Imaging modality revealed numerous nodules throughout the abdominal cavity. Peritoneal dissemination of the ascending colon or ovarian cancer and pseudomyxoma peritonei were considered in the preoperative differential diagnoses, and laparoscopic ileocecal resection was performed. Intraperitoneal observation revealed numerous white nodules in the peritoneum, omentum and Douglas fossa. Both the nodules and tumor were diagnosed as mucinous carcinoma based on a pathology report. The tumor invasion depth was limited to muscularis propria, and no regional lymph node metastasis was detected. Peritoneal dissemination of the ascending colon cancer was considered. We report a rare case of multiple peritoneal dissemination of T2 colorectal cancer without lymph node metastases.

A case of duodenal duplication cyst mimicking a pancreatic pseudocyst with intracystic hemorrhage.

BACKGROUND: Duodenal duplication cysts in adults are rare, and a preoperative diagnosis remains difficult because clinical manifestations are nonspecific and variable. We describe a case of a duodenal duplication cyst mimicking a pancreatic pseudocyst with repeated intracystic hemorrhage. CASE PRESENTATION: A 47-year-old male who complained of upper abdominal pain and vomiting was referred to our hospital. He was a heavy drinker and had a past history of hospitalization for alcoholic chronic pancreatitis. Plain abdominal computed tomography (CT) showed a cystic lesion of 7 cm in size in the lumen near the second part of the duodenum. The cystic lesion showed high density inside. Gastrointestinal endoscopy revealed that the lumen of the duodenum was deformed by a submucosal tumor-like mass and the endoscope could not pass through it, but active bleeding was not seen in the lumen of the duodenum. On the fourth day of hospitalization, anemia progressed and contrast-enhanced CT demonstrated a high-density spot on the wall of the cystic lesion. A pancreatic pseudocyst complicated with intracystic hemorrhage was preliminarily considered. Angiography was immediately performed, and a pseudoaneurysm was identified in the branch of the anterior superior pancreaticoduodenal artery (ASPDA). Transcatheter arterial embolization (TAE) was performed. Anemia did not progress after that, and follow-up CT showed reduction in the size of the cystic lesion. Afterward, the same symptoms recurred twice and surgical treatment was performed for the pancreatic pseudocyst with repeated intracystic hemorrhage. Macroscopically, a cystic mass of 5 cm in size was adjacent to the second part of the duodenum on the pancreas side. A pinhole-sized communication was identified between the cyst and the duodenum lumen. Microscopically, the cyst wall was composed of gastric mucosa and shared a common proper muscle layer with the duodenum. Chronic ulcers and erosions were seen in the cyst. Based on these findings, a diagnosis of duodenal duplication cyst was made. CONCLUSIONS: Duodenal duplication cysts in adults have seldom been reported and should be considered as a differential diagnosis for a patient with a cystic lesion adjoining the duodenum.