Immunohistochemistry in surgical pathology practice: a current perspective of a simple, powerful, yet complex, tool.

Immunohistochemistry (IHC) is a powerful tool in the surgical pathologists' armamentarium. The requests for IHC and the list of monoclonal antibodies have increased tremendously in the past decade. Issues concerning technical reproducibility, uniformity of interpretation, inter-laboratory comparability, and quality assurance are assuming greater importance due to the increased availability of IHC and its impact on diagnosis and therapy. An attempt has been made to give a current perspective of this simple and yet, in some aspects, a complex tool.

Well-differentiated adenocarcinoma of the rectosigmoid colon associated with psammoma bodies: a case report.

This report documents an unusualfinding of scattered psammomatous-type calcification in a well-differentiated adenocarcinoma of the rectosigmoid colon in a 54-year-old woman. The clinical relevance of this histologic feature is discussed, in light of review of the literature.

Laryngeal chondrometaplasia: a great mimic of chondrosarcoma.

Chondrometaplasia of larynx is a rare entity with an unknown etiopathogenesis. The lesion remains asymptomatic unless it reaches a large size and a history of trauma is usually elicited. It is a known pitfall in diagnostic evaluation and a clinically significant differential considered in evaluation of cartilaginous tumors of the larynx. A 66-year-old man presented with a nodular mass of right side of neck, progressive hoarseness of voice and pain, and a suspicious growth in the right glottic region. A CT followed by an MRI one month later revealed a slow growing ill defined thickening and enhancement of the supraglottic soft tissues, predominantly involving the submucosa, along the greater cornu on the left side of the thyroid cartilage, with extra-chondral enhancement and was suggested to be of infectious etiology. On neck exploration a lesion clinically suspected to be a chondrosarcoma was excised along with the right ala of the thyroid cartilage. The tissue processed entirely, revealed features consistent with chondrometaplasia of larynx. The importance of distinguishing this lesion from cartilaginous tumors is emphasized.

CD10 in diffuse uterine leiomyomatosis: a case report along with a few comments on histogenesis.

Diffuse uterine leiomyomatosis (DUL) is a rare entity with an unknown etiopathogenesis. A 24 years old female presented with abdominal discomfort and menorrhagia. Clinical and ultrasonographic examination revealed an enlarged uterus. The hysterectomy specimen showed a symmetrically enlarged uterus with a bosselated external surface. The cut surface showed multiple nodules of varying sizes diffusely involving the myometrium. Microscopically, the nodules were leiomyomas of varying degrees of cellularity. Some of the leiomyomas showed an increased vascularity either in the form of congeries of blood vessels with a lobular arrangement or occasionally as foci of 2-3 vessels. The vessels were surrounded by whorls of spindle cells. On immunohistochemistry the leiomyomas expressed vimentin, smooth muscle actin (SMA), desmin and CD10: the cells whorling around the blood vessels expressed vimentin, SMA and focally desmin and were negative for CD10 and HMB-45. The aim of this paper is to document that CD10 is expressed in diffuse uterine leiomyomatosis and discuss the histogenesis of DUL.