Nodular hyperplasia of Bartholin's gland.

AIMS: There has been very little mention of benign solid lesions of the Bartholin's gland (BG) in pathology and gynaecology textbooks, and very few cases have been reported in the literature. Among these lesions, the distinction between nodular hyperplasia (NH) and adenoma has not been well defined. We report ten cases of NH of the BG, describe their clinicopathological, immunohistochemical and ultrastructural findings, and review the literature.

METHODS: We examined retrospectively all lesions involving BGs from our surgical pathology records from 1990 to 2004 with emphasis on NH. To separate NH from adenoma, we applied the criteria proposed by Koenig and Tavassoli. Special stains (PAS with and without prior digestion, Mayer's mucicarmine and Alcian blue with and without hyaluronidase) and immunohistochemistry (CAM5.2, AE1/AE3, HMWK, monoclonal CEA, EMA, ER, PR, ALA, SMA, Ki-67, p53 and polyclonal CEA) were performed on NHs. Two cases were examined ultrastructurally.

RESULTS: Using specific criteria, ten cases (age range 23-45 years; mean 36.1) of NH were identified, two of which were diagnosed previously as adenoma, but re-classified as NH. Clinically, these lesions were described either as Bartholin's duct cysts (BDCs) or vulvar lumps. Grossly, NHs were solid, tan and unencapsulated, measuring 12.5-45.0 mm in maximum dimension (mean 23.8). Histologically, the NHs were composed of a proliferation of mucus-secreting acini with preservation of the normal duct-to-acinar relationship. Chronic inflammation and squamous metaplasia were present. Eight lesions focally involved the surgical margins. Intracytoplasmic and intra-luminal secretions were positive for PAS with and without digestion, Alcian blue with and without hyaluronidase and mucicarmine. All lesions showed positive staining for CAM5.2, AE1/AE3, HMWK, EMA, and polyclonal CEA. There was negative staining for Ki-67, ER, PR, ALA, p53 and monoclonal CEA. Periacinar myoepithelial cells stained for SMA. Ultrastructurally, the findings included abundant intracytoplasmic secretory granules, granulofibrillar bodies, prominent Golgi and ribosomes. Myoepithelial cells were identified. There was no tumour recurrence or malignant transformation in eight patients with clinical follow-up.

CONCLUSION: NH of the BG is a rare lesion with benign behaviour. It is a distinct entity and can be separated histologically from an adenoma.