Clinicopathological and Immunohistochemical Study of 14 Cases of Morbihan Disease: An Insight Into Its Pathogenesis.

Morbihan disease (MORD) is rare with only 45 clear-cut cases previously reported. Histopathologic findings are supposed to be nonspecific. We report 14 patients and review the previous cases. To characterize the clinicopathologic findings, outcomes, and immunophenotype of MORD. Inclusion criteria were a clinical picture of persistent, nonpitting edema affecting the mid and or upper third of the face and histopathological findings fitting previous reports and exclusion of other entities. The majority of our patients were males (71.5%) with a male/female ratio of 10/4. The mean age when diagnosed was 58.8 years. Eyelids and forehead were the most frequently involved areas. Two of the patients presented previous rosacea. Most constant histopathological findings were lymphatic vessel dilatations in the upper dermis and the presence of mast cells (7.5 in 10 high-power field as a mean). Mild edema was also present in most of the cases. Granulomas were found in 7 of the cases, and immunostaining with CD68 and CD14 only revealed an additional case. MORD occurs more in middle-aged males, not associated with rosacea and mostly affects eyelids and forehead. Granulomas are not mandatory for the diagnosis. Histopathology of MORD fits within the spectrum of localized lymphedema.