Incidental Diagnosis of Lymphangioleiomyomatosis (LAM) in Gynecological Surgery – A Case Series

Background: Lymphangioleiomyomatosis (LAM) is a rare, slow progressing, low-grade neoplasm that primarily effects premenopausal women. The disease is of systemic nature and well known for its pulmonary involvement with cystic destruction, but extra-pulmonary disease may occur and present as renal angiomyolipoma or lymphangioleiomyomtous lesions in different organs. LAM-associated lesions may present mutations in the tuberous sclerosis complex gens and may develop sporadically or in the context of tuberous sclerosis as hereditary disease. Incident LAM may represent the sentinel finding of the disease.

Methods: A data base research was performed for LAM in gynecological surgical specimens. H&E-stained slides were re-examined for exact localization of the LAM within the specimen. Immunohistochemical stains were reevaluated for expression patterns. Clinical data were retrieved for the presence of tuberous sclerosis.

Results: The age ranged from 32 to 78 years (mean=54 yrs, median=55 yrs), with 8/13 were≤ 55 years. One woman had a history of LAM with lung involvement and another woman had clinical diagnosis of tuberous sclerosis. Overall, no history of renal angiomyolipoma or PEComa noted. 9/13 women underwent surgery for gynecological malignancy, 2/13 for endometriosis and complex atypical endometrium hyperplasia and 2/13 for pelvic discomfort and pelvic lymphadenopathy. On histological examination 10/13 women incidentally presented LAM involvement in 1 to 9 lymph nods (median=1,5) with a lesion size of 0,5 to 12 mm (median=2,3 mm), mainly located subcapsular or in the nodal parenchyma, one half with extranodal spread in the fatty tissue. 3/13 women showed extranodal involvement of the retroperitoneum, myometrium, and the hilum of the ovary. The neoplasm stained in most cases positive for HMB45 (patchy 9/13, focal 1/13), for desmin (4/7) and smooth muscle actin (3/3), with negativity for borad spectrum cytokeratins (6/6) and S100 (3/3). LAM was associated with tuberous sclerosis in 2/13 patients.

Conclusion: LAM is a rare systemic disease, which mainly involves the lungs. Nevertheless, abdominal nodal or extranodal manifestations may occur and therefore should be considered as a differential diagnosis in the spectrum of abdominal spindle cell neoplasm. It is important to report the incidental finding of even small foci of LAMs as a clue for women with yet unrecognized tuberous sclerosis complex.

Publication History

Article published online:
11 June 2024