[Mesenteric panniculitis]

Clinical significance of mesenteric panniculitis-like abnormalities on abdominal computerized tomography in patients with malignant neoplasms

AIM

To clarify the association of malignancy with mesenteric panniculitis-like changes on computed tomography (CT).

METHODS

All abdominal CT scans performed at NorthShore University HealthSystem showing mesenteric panniculitis from January 2005 to August 2010 were identified in the Radnet (RadNet Corporation, Los Angeles, CA) database. Patients with a new or known diagnosis of a malignancy were included for this analysis. Longitudinal clinical histories were obtained from electronic medical records.

RESULTS

In total, 147794 abdominal CT scans were performed during the study period. Three hundred and fifty-nine patients had mesenteric panniculitis (MP)-like abnormalities on their abdominal CT. Of these patients, 81 patients (22.6%) had a known history of cancer at the time of their CT scan. Nineteen (5.3%) had a new diagnosis of cancer in concurrence with their CT, but the majority of these (14/19, 74%) were undergoing CT as part of a malignancy evaluation. Lymphomas were the most common cancers associated with MP-like findings on CT (36 cases, 36%), with follicular lymphoma being the most frequent subtype (17/36). A variety of solid tumors, most commonly prostate (7) and renal cell cancers (6) also were seen. CT follow up was obtained in 56 patients. Findings in the mesentery were unchanged in 45 (80%), worsened in 6 (11%), and improved in 5 patients (9%). Positron emission tomography (PET) scans performed in 44 patients only showed a positive uptake in the mesenteric mass in 2 patients (5%).

CONCLUSION

A new diagnosis of cancer is uncommon in patients with CT findings suggestive of MP. MP-like mesenteric abnormalities on CT generally remain stable in patients with associated malignancies. PET scanning is not recommended in the evaluation of patients with mesenteric panniculitis-like findings on CT.

Mesenteric panniculitis: an update

In 1924, mesenteric panniculitis was first described in the medical literature by Jura et al. as 'retractile mesenteritis.' It represents a spectrum of disease processes characterized by degeneration, inflammation and scarring of the adipose tissue of the mesentery. The clinical presentations vary according to the stage of the disease and they include abdominal pain, weight loss, nausea and vomiting. Computed tomography findings are usually diagnostic. The gross findings include thickening of the mesentery, mass lesions and adhesion to the surrounding organs. Histologically, there is a chronic inflammatory process involving the adipose tissue with fat necrosis, inflammation and fibrosis. Herein, the authors address the clinicopathological features, course, treatment and pathogenetic mechanisms of mesenteric panniculitis.