An adult male presented with abdominal pain and diarrhea. A Barium meal follow through revealed mildly narrowed lumen of a loop with stretched and fixed rigid walls. At CT Contrast study was performed which showed a stellate shaped enhancing mesenteric lesion with adjacent bowel wall thickening. This mass lesion represents

**Core Concept**
The clinical presentation of abdominal pain and diarrhea, coupled with radiological findings of a narrowed loop with fixed and rigid walls, and a stellate-shaped enhancing mesenteric lesion with adjacent bowel wall thickening, suggests a diagnosis related to inflammation and fibrosis of the bowel wall. This scenario is characteristic of a specific type of bowel pathology that involves chronic inflammation and fibrosis.

**Why the Correct Answer is Right**
The stellate-shaped enhancing mesenteric lesion with adjacent bowel wall thickening is indicative of a mesenteric desmoid tumor, also known as a mesenteric fibromatosis. This type of tumor arises from the mesenteric tissue and can cause bowel obstruction due to its mass effect. The chronic inflammation and fibrosis lead to a desmoplastic reaction, resulting in the characteristic rigid and fixed bowel wall. The CT contrast study helps to distinguish this lesion from other types of mesenteric masses, such as lymphadenopathy or metastatic disease.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because a mesenteric desmoid tumor is a type of benign tumor, whereas option A implies a malignant process.
**Option B:** This option is incorrect because a mesenteric adenitis is an inflammatory process involving the mesenteric lymph nodes, which typically does not present with a stellate-shaped enhancing lesion.
**Option C:** This option is incorrect because a mesenteric panniculitis is a type of inflammatory process involving the mesenteric fat, which typically presents with a more diffuse and ill-defined pattern on imaging.

**Clinical Pearl / High-Yield Fact**
The clinical presentation of a stellate-shaped enhancing mesenteric lesion with adjacent bowel wall thickening should raise suspicion for a mesenteric desmoid tumor. This diagnosis is often challenging to make based on imaging alone, and a high index of suspicion is required to avoid missing this diagnosis.

**Correct Answer:** C.

✓ Correct Answer: B. Mesenteric carcinoid tumor