Pedunculated hamartomatous polyp of the appendix: report of a case. Surg Today. 2013;43:191-193. [PMID: 22610489 DOI: 10.1007/s00595-012-0190-0]

Mucosal prolapse syndrome-like inflammatory polyp protruding from the appendiceal orifice masquerading as an appendiceal neoplasm: A rare case report

We describe a case of a mucosal prolapse syndrome (MPS)-like inflammatory polyp protruding from the appendiceal orifice, mimicking an appendiceal neoplasm. A 48-year-old man presented with lower abdominal pain and elevated white blood cell count and C-reactive protein level. Computed tomography showed a swollen appendix with multiple small saccular lesions and periappendiceal fat stranding and small saccular lesions in the ascending colon and cecum. Ultrasonography showed a swollen appendix 25 mm in diameter with multiple saccular structures and a periappendiceal high-echoic area, suggesting appendiceal diverticulitis. Colonoscopy revealed an erythematous lesion protruding from the appendiceal orifice. An ileocecal resection was performed based on a preoperative diagnosis of appendiceal diverticulitis and tumor. Histopathological examination of the appendix showed multiple mucosal herniations with infiltration of inflammatory cells, indicating appendiceal diverticulitis. The tumor was characterized by glandular duct hyperplasia and stromal expansion with smooth muscle hyperplasia and was diagnosed as an inflammatory polyp resembling an MPS lesion. Although several studies have shown the macroscopic and endoscopic appearance of MPS-like inflammatory lesions associated with colonic diverticular disease, this case was the first to present an inflammatory polyp associated with appendiceal diverticulitis in which the lesion protruding from the appendiceal orifice was masquerading as an appendiceal neoplasm.

Appendiceal cancer leading to intussusception detected incidentally during follow-up for Peutz-Jeghers syndrome

Peutz-Jeghers syndrome is an autosomal dominant disorder characterized by hamartomatous polyposis, pigmentation, and malignant tumors. We report a case of ileocecal carcinoma that was incidentally detected during follow-up for Peutz-Jeghers syndrome. A 39-year-old man with solitary Peutz-Jeghers syndrome had undergone three abdominal surgeries. He had been followed up via upper and lower gastrointestinal endoscopy and small intestinal endoscopy. In the endoscopic examination of the lower gastrointestinal tract, a 35 mm large, bumpy, elevated lesion was observed in the cecum. This lesion was not observed 9 months earlier during lower endoscopy. Biopsy of the specimen confirmed tubulovillous adenoma and carcinoma. This lesion was judged to be an indication for operation, and we performed ileocecectomy + D3 lymph node dissection. From the excised specimen, poorly differentiated carcinoma and adenoma components in contact with Peutz-Jeghers-type polyps in the appendix were recognized. A review of the computed tomography image obtained 2 years ago confirmed appendiceal swelling. We suspect that the ileocecal carcinoma in the appendix may have rapidly developed within the 9 months, and was incidentally detected on lower endoscopic examination during follow-up. For the prevention of appendicular tumorigenesis, prophylactic appendectomy may be considered in certain cases during follow-up for Peutz-Jeghers syndrome.

Peutz-Jeghers Type Polyp of the Appendix with Review of Literature

Hamartomatous polyps of Peutz-Jeghers type are strongly associated with Peutz-Jeghers polyposis syndrome and are predominantly encountered in the small intestine. Sporadic cases are uncommonly reported. We report a case of a polyp identified incidentally in the appendix of a patient undergoing diagnostic imaging due to a history of hepatitis C infection. Histopathologic evaluation after appendectomy showed a polyp with bands of muscularis mucosae bundles with arborizing architecture and variable amounts of inspissated mucin, morphologically indistinguishable from Peutz-Jeghers type hamartomatous polyp. A family or personal history of abdominal cancers was not reported by the patient, suggesting a sporadic occurrence. Next generation sequencing revealed only two pathogenic low-level STK11 mutations, presumed to be somatic. In conclusion, this is an unusual case of a sporadic Peutz-Jeghers type polyp occurring in the appendix.

Solitary Peutz-Jeghers-type appendiceal hamartomatous polyp growing into the terminal ileum

Solitary Peutz-Jeghers type hamartomatous polyp is rare. It is considered to be related to a variant Peutz-Jeghers syndrome (PJS) and may be a separate disease entity. A 50-year-old man was referred to our hospital with a diagnosis of intussusception in the terminal ileum and underwent segmental ileal resection with appendectomy. We identified a 3.5-cm diameter polyp arising from the appendix with ingrowth into the terminal ileum. The polyp was confirmed to be a hamartomatous polyp of Peutz-Jeghers-type, histologically. However, the patient had no characteristic manifestations of PJS such as mucocutaneous pigmentation and family history. There are few reports of appendiceal hamartomatous polyp in PJS patients and solitary appendiceal hamartomatous polyp is even rarer. Also, rather than telescoping, ours is the first reported intussuscepted lesion, to the best of our knowledge.