A 5-year-old child was admitted to the hospital with a history of prolapsing rectal mass and painless rectal bleeding. The histopathological image of the mass is shown below. What is the most likely diagnosis?

Explanation

## Correct Answer: D. Juvenile polyp Juvenile polyps are the most common colonic polyps in children, accounting for 90% of pediatric polyps. The clinical presentation of a 5-year-old with a prolapsing rectal mass and painless rectal bleeding is pathognomonic for juvenile polyp. These polyps are benign hamartomas with a characteristic histopathology showing cystic dilated glands, abundant lamina propria, and a smooth surface. The prolapsing nature occurs because juvenile polyps are typically pedunculated and located in the rectosigmoid region, making them prone to intussusception and prolapse through the anus. The painless bleeding results from mucosal ulceration at the polyp surface. Unlike adenomatous polyps, juvenile polyps have virtually no malignant potential (risk <1%), and most regress spontaneously by adolescence. The diagnosis is confirmed by histopathology showing the characteristic hamartomatous architecture with cystic glands and minimal dysplasia. Management is typically polypectomy for symptomatic polyps, which is both therapeutic and diagnostic. ## Why the other options are wrong **A. Peutz Jegher syndrome** — Peutz-Jeghers syndrome presents with multiple hamartomatous polyps throughout the GI tract (especially small bowel) and characteristic mucocutaneous pigmentation (brown macules on lips and buccal mucosa). A solitary rectal polyp in a 5-year-old without pigmentation or family history does not fit this syndrome. PJS polyps are larger and carry malignant potential, requiring surveillance. **B. Villous adenoma** — Villous adenomas are true adenocarcinomas with significant malignant potential (40% risk of malignancy), typically occurring in older adults (>50 years). They present with mucoid diarrhea and electrolyte loss, not prolapse. Histologically, they show villous architecture with dysplasia, not the cystic hamartomatous pattern seen in juvenile polyps. Age and presentation make this diagnosis unlikely. **C. Tubular adenoma** — Tubular adenomas are true adenomas with dysplastic epithelium and malignant potential, typically found in older patients. They do not prolapse and do not present with this acute symptomatic picture in children. Histologically, they show tubular glandular structures with dysplasia, not the characteristic cystic dilated glands and hamartomatous stroma of juvenile polyps. ## High-Yield Facts - **Juvenile polyps** are the most common colonic polyps in children (90% of pediatric polyps), typically presenting between ages 2–8 years. - **Prolapsing rectal mass with painless bleeding** is the classic presentation; polyps are pedunculated and located in rectosigmoid, prone to intussusception. - **Malignant potential <1%**; juvenile polyps are benign hamartomas that regress spontaneously by adolescence in most cases. - **Histopathology** shows cystic dilated glands, abundant lamina propria, smooth surface, and minimal dysplasia—distinguishing feature from adenomas. - **Management** is polypectomy for symptomatic polyps; no surveillance required due to negligible malignant risk. ## Mnemonics **JPP: Juvenile Polyp Presentation** **J**uvenile (age 2–8) | **P**rolapse + bleeding | **P**edunculated rectosigmoid. Use when you see a child with rectal bleeding and a prolapsing mass. **HAM: Hamartoma vs Adenoma** **H**amartoma (Juvenile) = benign, cystic glands, no dysplasia, <1% malignancy | **A**denoma (Tubular/Villous) = dysplasia, malignant potential, older patients. Discriminates juvenile polyp from adenomas. ## NBE Trap NBE may pair "adenoma" with "polyp" to trap students into choosing tubular or villous adenoma, forgetting that juvenile polyps are hamartomas, not true adenomas. The prolapsing presentation is a red herring that should immediately point to the pedunculated juvenile polyp in a young child. ## Clinical Pearl In Indian pediatric practice, a child presenting with rectal bleeding and a mass visible at the anal verge should raise immediate suspicion for juvenile polyp. Many are managed conservatively with observation, as spontaneous regression is common; polypectomy is reserved for symptomatic cases or those causing intussusception—avoiding unnecessary surgery in a benign condition. _Reference: Robbins and Cotran Pathology of the Gastrointestinal Tract, Ch. 17; OP Ghai Pediatrics, Ch. Gastroenterology_