Reproductive System, Male

Testis, Germ Cell - Exfoliation

Narrative

Comment:

Germ cells may undergo degeneration and/or apoptosis within the seminiferous epithelium, or they may lose contact with the surrounding Sertoli cell cytoplasmic processes and be shed into the tubular lumen (Figure 1 and Figure 2). Often the exfoliated germ cells retain relatively normal morphology. The cells will rapidly be transported into the epididymis and will be present in the ductular lumens. The finding should not be confused with artifactual sloughing of germ cells caused by squeezing of the testis during necropsy dissection. In the case of sloughing due to necropsy trauma, germ cells will not be seen in the epididymis. Germ cell exfoliation has been described as a predominant finding following administration of phthalate esters and microtubule inhibitors such as colchicine and the fungicide carbendazim.

Recommendations:

The term "germ cell exfoliation" should be reserved for those situations where there is extensive shedding of germ cells into the lumen as a predominant finding. In those situations, germ cell exfoliation should be diagnosed and graded and should be discussed in the pathology narrative if the incidence and/or severity appears to be related to chemical administration. Bilateral involvement should be diagnosed when present. If there is significant concurrent germ cell degeneration, that should also be diagnosed and given a severity grade.

References:

Correa LM, Nakai M, Strandgaard CS, Hess RA, Miller MG. 2002. Microtubules of the mouse testis exhibit differential sensitivity to the microtubule disruptors carbendazim and colchicine. Toxicol Sci 69:175-182.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/12215672

Creasy DM. 2001. Pathogenesis of male reproductive toxicity. Toxicol Pathol 29:64-76.

Full Text: http://tpx.sagepub.com/content/29/1/64.full.pdf

Creasy D, Bube A, de Rijk E, Kandori H, Kuwahara M, Masson R, Nolte T, Reams R, Regan K, Rehm S, Rogerson P, Whitney K. (2012). Proliferative and nonproliferative lesions of the rat and mouse male reproductive system. Toxicol Pathol 40:40S-121S.

Abstract: https://doi.org/10.1177/0192623312454337

Nakai M, Hess RA. 1994. Morphological changes in the rat Sertoli cell induced by the microtubule poison carbendazim. Tissue Cell 26:917-127.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/7886678

Russell LD, Malone JP, MacCurdy DS. 1981. Effect of the microtubule disrupting agents, colchicine and vinblastine, on seminiferous tubule structure in the rat. Tissue Cell 13:349-367.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/7314074

All Images

Testis, Germ cell - Exfoliation in a male Harlan Sprague-Dawley rat. Exfoliated germ cells are present in seminiferous tubule lumens. (Photograph courtesy of Dr. D. Creasy.)

Testis, Germ cell - Exfoliation in a male Harlan Sprague-Dawley rat. Higher magnification of Figure 1 showing germ cells in seminiferous tubule lumens. (Photograph courtesy of Dr. D. Creasy.)

Authors and Reviewers

Authors

Dianne M. Creasy, PhD, Dip RCPath, FRCPath
Dianne Creasy Consulting LLC
Pipersville, PA

Robert R. Maronpot, DVM, MS, MPH, DACVP, DABT, FIATP
Senior Pathologist
Experimental Pathology Laboratories, Inc.
Research Triangle Park, NC

Dipak K. Giri, DVM, PHD, DACVP
Toxicologic Pathologist
Integrated Laboratory Systems, Inc.
Research Triangle Park, NC

Reviewers

Mark F. Cesta, DVM, PhD, DACVP
Staff Scientist, NTP Pathologist
Cellular and Molecular Pathology Branch
Division of the National Toxicology Program
National Institute of Environmental Health Sciences
Research Triangle Park, NC

David E. Malarkey DVM, PhD, DACVP, FIATP
Head, National Toxicology Program Pathology Group
Cellular and Molecular Pathology Branch
Division of the National Toxicology Program
National Institute of Environmental Health Sciences
Research Triangle Park, NC