Endoscopic submucosal dissection as excisional biopsy for anorectal malignant melanoma: A case report.

BACKGROUND: Anorectal malignant melanoma (AMM) is a rare disorder with an extremely poor prognosis. Although there is currently no consensus on the treatment methods for AMM, surgical procedures have been the most common treatment methods used until now. We recently encountered a case of AMM that we diagnosed using endoscopic submucosal dissection (ESD). To our knowledge, this is the first case of ESD for AMM, suggesting that ESD can potentially be a diagnostic and treatment method for AMM. CASE SUMMARY: A 77-year-old woman visited our hospital with a chief complaint of anal bleeding and a palpable rectal mass. Colonoscopy revealed a 20-mm protruded lesion in the lower rectum. After obtaining biopsy specimens from the lesion, although a malignant rectal tumor was suspected, a definitive diagnosis was not made. Endoscopic ultrasonography revealed tumor invasion into the submucosal layer but not the muscular layer. Therefore, we performed an excisional biopsy using ESD. Immunohistochemical examination of the ESD-resected specimen revealed tumor cells positive for Human Melanin Black-45, Melan-A, and S-100. Moreover, the tumor cells lacked melanin pigment; thus, a diagnosis of amelanotic AMM was made. Although the AMM had massively invaded the submucosal layer and both lymphatic and venous invasion were present, we closely monitored the patient without any additional therapy on the basis of her request. Six months after ESD, local recurrence was detected, and the patient consented to wide local excision. CONCLUSION: It is suggested that ESD is a potential diagnostic and treatment method for AMM.

Gastric adenocarcinoma of fundic gland type spreading to heterotopic gastric glands.

Herein, we present a case of gastric adenocarcinoma of fundic gland type (GA-FG) spreading to heterotopic gastric glands (HGG) in the submucosa. A 58-year-old man with epigastric pain was referred to our hospital and underwent an esophagogastroduodenoscopy. A Borrmann type II gastric cancer at the antrum and a 10 mm submucosal tumor-like lesion in the lesser curvature of the upper third of the stomach were detected. Histological examination of the biopsy specimens obtained from the submucosal tumor-like lesion suggested a GA-FG. Therefore, endoscopic submucosal dissection was performed as excisional biopsy, and histopathological examination of the resected specimen confirmed a GA-FG and HGG proximal to the GA-FG. Although the GA-FG invaded the submucosal layer slightly, the submucosal lesion of the GA-FG had a poor stromal reaction and was located just above the HGG in the submucosa. Therefore, we finally diagnosed the lesion as a GA-FG invading the submucosal layer by spreading to HGG.

A case of small intestinal intussusception caused by anisakiasis diagnosed and treated by upper gastrointestinal endoscopy.

A 35-year-old man attended our hospital with complaining of epigastric pain and vomiting. He was diagnosed with bowel intussusception based on the target sign revealed in the upper jejunum by abdominal computed tomography. However, the cause of the intussusception was not clear. Insertion of an endoscope into the jejunum revealed prominent edema in the upper part of the jejunum, and Anisakis simplex was identified at the site and removed. Symptoms rapidly improved after endoscopic treatment. We report this case because surgery was avoidable and because we are aware of no previous reports of small intestinal intussusception caused by anisakiasis that has been diagnosed and treated endoscopically.

A case of liver abscess caused by appendicitis which was considered to be drained from hepatobronchial fistula.

A 52-year-old man was referred to our hospital complaining of right lower abdominal pain. He was diagnosed with appendicitis complicated with a liver abscess and underwent an appendectomy. After antibiotic treatment following surgery, the liver abscess penetrated the right lung, which was considered to be drained from a hepatobronchial fistula. Due to the effect of drainage, the liver abscess immediately improved and the patient was subsequently discharged.