Granular cell variants of cutaneous basal cell tumors from three dogs are described. These tumors resemble a granular cell variant of basal cell tumor (carcinoma) in man. The tumors are characterized by classical basal cells as well as granular cells with numerous cytoplasmic granules. These granules are cytoplasmic vacuoles 0.3 μm to 1.5 μm that seem to be secondary lysosomes; they usually contain many small (42 nm), membrane-bound vesicles. No natural, non-neoplastic counterpart of these granular cells is known to exist in the skin, and the significance of the production and accumulation of the small vesicles is not known. The cytoplasmic granules, and their contents, resemble the granules of granular cell “myoblastoma” although granular basal cells are of epithelial origin.
References
1.
AparicioS.R.LumsdenC.E.:
Light- and electron-microscopic studies on the granular cell myoblastoma of the tongue.
J Pathol97:
339–355,
1969.
2.
BangleR.:
A morphological and histochemical study of the granular-cell myoblastoma.
Cancer5:
950–965,
1952.
ChurukianC.J.SchenkE.A.:
A modification of Pascual's argyrophil method.
J. Histotechnol2:
102–103,
1979.
6.
GrimeliusL.WilanderE.:
Silver stains in the study of endocrine cells of the gut and pancreas.
Invest Cell Pathol3:
3–12,
1980.
7.
HartmanK.S.:
Granular-cell ameloblastoma. A survey of twenty cases from the Armed Forces Institute of Pathology.
Oral Surg38:
241–253,
1974.
8.
HullandT.J.:
Tumors of muscle. In:
Tumors in Domestic Animals,
ed. Moulton,
2nd ed.,
pp. 75–88.
University of California Press, Berkeley-Los Angeles-London,
1978.
9.
KurosumiK.:
Electron microscopic analysis of the secretion mechanisms.
Int Rev Cytol11:
1–124,
1961.
MisdorpW.Nauta-van GelderH.L.:
“Granular-cell myoblastoma” in the horse. A report of 4 cases.
Pathol Vet5:
385–394,
1968.
12.
NavarreteA.R.SmithM.:
Ultrastructure of granular cell ameloblastoma.
Cancer27:
948–955,
1971.
13.
NielsenS.W.:
Glands of the canine skin—Morphology and distribution.
Am J Vet Res14:
448–454,
1953.
14.
ParkerG.A.BothaW.Van DellenA.CaseyH.W.:
Cerebral granular cell tumor (myoblastoma) in a dog: Case report and literature review.
Cornell Vet68:
506–520,
1978.
15.
ParkerG.A.NovillaM.N.BrownA.C.FlorW.J.StedhamM.A.:
Granular cell tumor (myoblastoma) in the lung of a horse.
J Comp Pathol89:
421–430,
1979.
16.
RodriguezE.M.CaorsiI.:
A second look at the ultrastructure of the Langerhans cell of the human epidermis.
J Ultrastruct Res65:
279–295,
1978.
17.
SmithK.R.:
The structure and function of the Haarscheibe.
J Comp Neurol131:
459–474,
1967.
18.
SobelH.J.AvrinE.MarquetE.SchwarzR.:
Reactive granular cells in sites of trauma. A cytochemical and ultrastructural study.
Am J Clin Pathol61:
223–234,
1974.
SobelH.J.MarquetE.AvrinE.SchwarzR.:
Granular cell myoblastoma. An electron microscopic and cytochemical study illustrating the genesis of granules and aging of myoblastoma cells.
Am J Pathol65:
59–78,
1971.
StannardA.A.PulleyL.T.:
Tumors of the skin and soft tissues. In:
Tumors in Domestic Animals,
ed. Moulton,
2nd ed.,
pp. 16–74.
University of California Press, Berkeley-Los Angeles-London,
1978.
23.
WadeT.R.AckermanA.B.:
The many faces of basal-cell carcinoma.
J Dermatol Surg Oncol4:
23–28,
1978.
24.
WeissE.FreseK.:
Tumors of the skin. In: International Histological Classification of Tumours of Domestic Animals.
Bull WHO50:
79–100,
1974.
25.
ZelicksonA.S.:
Ultrastructure of Normal and Abnormal Skin.
pp. 54, 132, 163.
Lea and Febiger, Philadelphia,
1967.
