Aspects of the biopsy of the testis from the pathologist's point of view are discussed. Direct enzyme-histochemical staining for alkaline phosphatase (dAP) on frozen sections of biopsies taken during operation is a useful diagnostic tool to aid surgeons in testis-sparing surgery. Biopsy of the contralateral testis for the diagnosis of carcinoma in situ (CIS) in patients with a testicular germ cell tumour is not standard of care in most countries because of the high rate of negative biopsies. Based on risk factors for germ cell tumours, i.p. microlithiasis, a patient population is defined in which the rate of CIS in the contralateral biopsy is about 25%. It is reiterated that the diagnosis of CIS in testicular biopsies requires expertise, and should not be carried out without immunohistochemistry for markers for CIS. As OCT3/4 is increasingly used as marker, it is important to be aware that it may be false-negative in biopsies fixed in Bouin's or Stieve's fixative. Preliminary results are presented on a series of biopsies from cryptorchid testes in infants and children allowing the definition of morphological and immunohistochemical criteria for delayed maturation of gonocytes and pre-CIS. © 2011 The Authors. International Journal of Andrology

Biopsy, Carcinoma in situ, Pathogenesis, Pathology, Precursor, Testis
dx.doi.org/10.1111/j.1365-2605.2011.01204.x, hdl.handle.net/1765/31248
International Journal of Andrology
Erasmus MC: University Medical Center Rotterdam

Oosterhuis, J.W, Stoop, J.A, Dohle, G.R, Boellaard, W.P.A, van Casteren, N.J, Wolffenbuttel, K.P, & Looijenga, L.H.J. (2011). A pathologist's view on the testis biopsy. International Journal of Andrology (Vol. 34). doi:10.1111/j.1365-2605.2011.01204.x