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childhood asymmetric labium majus enlargement

Wednesday 14 September 2005

Childhood asymmetric labium majus enlargement (CALME) couldrepresent 22% of all pediatric vulvar soft tissue masses and 3% of all vulvar lesions biopsied. It is a distinctive clinicopathologic entity of pre- and early puberty.


- Age range: 3.9 to 13.2 years
- enlargement of 1 or occasionally both labia majora
- expansion of the labium majus without definable borders
- fibro-fatty tissue from 2 to 8 cm in greatest dimension
- usual constituents of vulvar soft tissue, with expansion of the fibrous component
- sparsely to moderately cellular interconnected bands encircled lobules of fat, blood vessels, and nerves
- bands consisted of plump and occasionally stellate or round fibroblasts immersed in an abundant pale myxoid matrix containing thin collagen fibers
- fibrous bands merged with thinner denser fibrous septa simlar to those seen in the vulva from age-matched controls
- variably abundant thin parallel elastic fibers


- fibroblasts immunohistochemically positive for estrogen and progesterone receptors


- fibroblasts with dilated rough endoplasmic reticulum cisternae and prominent nuclear fibrous laminae
- extracellular matrix contained precollagen, collagen, elastic fibers, and numerous proteoglycan granules


- normal karyotype


- Local recurrence: 50%


- Vargas SO, Kozakewich HP, Boyd TK, Ecklund K, Fishman SJ, Laufer MR, Perez-Atayde AR. Childhood asymmetric labium majus enlargement: mimicking a neoplasm. Am J Surg Pathol. 2005 Aug;29(8):1007-16. PMID: 16006794