[Incidental diagnosis of lymphangioleiomyomatosis in gynecological surgery-a case series].

Background: Lymphangioleiomyomatosis (LAM) is a rare, slow progressing, low-grade neoplasia that primarily effects young women. The disease is well known for its pulmonary involvement with cystic destruction, but extra-pulmonary disease may occur. LAM is associated with mutations in the TSC 1 or TSC 2 genes and may develop sporadically or in the context of hereditary disease tuberous sclerosis complex (TSC). Incident LAM may represent the sentinel finding of the disease.

Objective: Raising awareness for rare extrapulmonary LAM lesions in retroperitoneum and pelvic cavity.

Methods: Data-based research was performed for LAM in gynecological surgical specimens. H&E-stained slides were re-examined, and immunohistochemical stains were re-evaluated. Clinical data were retrieved for the presence pulmonary LAM or TSC.

Results: A total of 13 cases were identified. The age of the patients ranged from 32 to 77 years, and 8/13 were ≤ 55 years. Two women had a history of pulmonary LAM and TSC. Most women underwent surgery for gynecological malignancy. On histological examination, 10/13 patients presented LAM in 1 to 9 lymph nodes with a lesion size of 0.5 to 12.0 mm, mainly located subcapsular or in the nodal parenchyma. Three of the 13 women showed extranodal involvement of the retroperitoneum, myometrium, and the hilum of the ovary. Immunohistochemically LAM was positive for HMB45, desmin, and smooth muscle actin.

Conclusion: LAM is a rare systemic disease that mainly involves the lungs. Nevertheless, extra-pulmonary manifestations may occur. It is important to report the incidental finding of even small foci of LAM within the pathology report. Incidental LAM may represent the sentinel lesion for pulmonary LAM and/or TSC.