Immunohistochemical and Ultrastructural Characterization of Granular Cell Tumors of the Female Reproductive Tract in Two Aged Wistar Rats

Abstract

Granular cell tumors of the reproductive tract in rodents granules with indistinct cell borders and were separated by have been reported primarily in the uterine cervix of mice collagen bundles or smooth muscle cells (Fig. 3). Scattered treated with estrogens.> Spontaneous cervical and vaginal within the mass were foci of perivascular and interstitial granular cell tumors occur rarely in the Fischer rat.' We mononuclear cell infiltrates. Both granular cell tumors were describe histopathologic, immunohistochemical, and ultra-periodic acid-Schiff positive and diastase resistant (Fig. 4) structural features of granular cell tumors in the uterine cer-and stained faintly with Alcian blue. Both tumors stained vix and vagina of two aged Wistar rats.positively for S-l 00 protein. The tumor from rat No. I had Tumor specimens were obtained from animals from a foci that stained positively for neuron-specific enolase. Nei-2-year carcinogenicity study. Rat No.1 was a 11O-week-old ther tumor stained for vim entin, desmin, or actin. Ultravehicle control female Wistar rat. Rat NO.2 was a l l O-week-structural examination of tumor tissue from rat No.2 reold female Wistar rat that had been treated intravenously vealed that cytoplasmic granules were actually large aggregates with a synthetic anticancer chemotherapeutic compound. (approximate average diameter 3 !Lm) of polymorphous maTreatment consisted of once daily dosing for 5 days, followed terial (Fig. 5a). The aggregates contained single membraneby a 23-day recovery period. This regimen was repeated for bound lysosomal bodies of various sizes (approximately 200-six dosing cycles. Vehicle consisted of N,N-dimethylacet-400 nm in diameter) and shapes, with electron-dense amoramide (DMA) in a lactic acid diluent. Neither the test sub-phous cores. Electron-dense bodies were packed together with stance nor vehicle possessed any known estrogenic proper-smaller, moderately electron-dense granular material that had ties.an approximate average diameter of 40 nm (Fig. 5b). CyTissues were fixed in 10% neutral buffered formalin, pro-toplasm also contained scattered profiles of free ribosomes, cessed for light microscopic examination, and stained with mitochondria, and mildly dilated rough endoplasmic retichematoxylin and eosin, Masson's trichrome, Alcian blue, and ulum. Nuclei were peripherally located and round to slightly periodic acid-Schiff. Three-micrometer deparaffinized sec-indented and contained dispersed euchromatin and a single tions were stained by the avidin biotin peroxidase immu-prominent nucleolus. Basal lamina were not seen; however, noperoxidase method as previously described.t' using rabbit a few poorly defined widely distributed cell junctions were polyclonal anti-bovine S-100 protein and neuron-specific observed. enolase (DAKO Corp., Carpinteria, CA), mouse monoclonal Granular cell tumors have been described in seminal vesanti-porcine vimentin (Biogenex, San Ramon, CA), anti-hu-icles and in uteri of 2-year-old untreated Naval Medical Reman desmin (DAKO Corp.), and acti...

Granular Cell Lesions in the Distal Female Reproductive Tract of Aged Sprague-Dawley Rats

“…Many of the tumors were distinct nodules within the muscularis or extended into the adventitia; however, others had indistinct borders and expanded along tissue planes and ligaments (Figs. [3][4][5][6]. A variant of the benign tumor contained foci of cells with decreased granularity and was identified as a granular cell tumor with spindle-cell component.…”

“…4,[7][8][9]11,17,20,22 On the light microscopic level, regardless of the species of origin and anatomic site, granular cell tumors are characterized by a uniform population of cells with abundant granular eosinophilic cytoplasm that is periodic acid-Schiff (PAS) positive and diastase resistant and typically with small basophilic nuclei. 17,20,22 Most granular cell tumors are positive with immunohistochemical markers for neuroectodermal origin such as S100 protein and neuron-specific enolase (NSE).…”

“…17,20,22 Most granular cell tumors are positive with immunohistochemical markers for neuroectodermal origin such as S100 protein and neuron-specific enolase (NSE). 2,3,4,15,16,18 Ultrastructurally, the hallmark of the tumor is the many lysosomal bodies. 6,20 Granular cell tumors are an enigma because no normal cell counterpart is known.…”

“…7,8 Single cases of spontaneous cervical or vaginal granular cell tumors have been reported in rats. 4,14 In one rat carcinogenicity study, a spectrum of lesions composed of granular cells occurred. Granular cell alterations of control and treated rats of this original study were examined microscopically with special stains and were evaluated ultrastructurally.…”

Intracranial Granular Cell Tumor in a Dog

“…GCT in the central nervous system (CNS) has been well documented in humans and rats but has seldom been reported in dogs and other animal species [2][3][4][5]7]. In animals, GCTs located in various tissues are most frequently encountered in rats, dogs, and horses [9,15].…”