An immunohistochemical study of basal cell carcinoma and trichoepithelioma

The histologic distinction between tricheopithelioma and basal cell carcinoma may be difficult in small biopsies. Immunohistochemical stains have been used to help make this distinction; however, published studies have generally been limited to a few antibodies. To this end we performed a comprehensive immunohistochemical analysis of 20 basal cell carcinomas and 10 tricheopitheliomas from our files, in search of a consistent pattern of reactivity to distinguish the neoplasms in biopsies. The antibodies used were: low molecular weight keratin (Cam 5.2), Cytokeratin 7, (CK7), Cytokeratin 20, (CK20), Carcino-embryonic antigen (CEA), CD30 (Ki-1), bcl-2, Ham 56, HPCA-I (CD34), and Ulex Europaeus type I. In our study, bcl-2 stained all but one basal cell carcinoma in a diffuse pattern, whereas all tricheopitheliomas showed staining of the outermost epithelial layer. No other stain proved to be an independent marker for either neoplasm and no consistent immunohistochemical profile for either neoplasm emerged. Thus, we conclude that bcl-2 may be of some value in distinguishing basal cell carcinoma from tricheopithelioma, limited by the quantitative nature of the difference in staining. Histologic criteria applied to H&E-stained sections remain the cornerstone of histologic diagnosis.

Pulmonary artery fibrous bands: report of a case with extensive lung infarction and superinfection with Coccidioides immitis, Pseudomonas, and acid-fast bacilli

A 46-year-old woman presented with shortness of breath and frequent lower respiratory tract infections. A ventilation-perfusion scan showed markedly reduced perfusion of the right lung, and pulmonary arteriogram showed stenosis of the right pulmonary artery. A right pneumonectomy revealed dense white fibrous bands partially occluding the pulmonary artery branches and two large abscess cavities filled with pus in the upper and lower lobes. Microscopic examination revealed extensive necrosis of lung parenchyma, suppurative granulomatous inflammation with Coccidioides immitis organisms and rare acid-fast bacilli. Pulmonary artery fibrous bands were originally believed to be congenital; however, they are now known to be sequelae of thromboembolic phenomena.

Congenital self-healing reticulohistiocytosis. Report of a case with 7-year follow-up and a review of the literature

A case of congenital self-healing reticulohistiocytosis in an otherwise healthy newborn boy is presented. Histological, immunohistochemical, and ultrastructural findings are described and the nosologic position of this entity is discussed.

An unusual case of Phormia regina myiasis of the scalp

The authors report a case of Calliphorine myiasis in the scalp of a 64-year-old woman caused by the larvae of Phormia regina (Black Blowfly). There was extensive blackening of the scalp and necrosis of the soft tissues, which is unusual in Phormia regina myiasis.