Granular cell basal cell carcinoma

A 69-year-old woman presented with a 2-year history of a slowly growing tumour on the nose. The clinical diagnosis was basal cell carcinoma (BCC) and a complete excision was performed. Histologically, the tumour had the general features of a BCC but with sheets and nests of cells with granular cytoplasmic changes in the centre of the lesion. A pathological diagnosis of granular cell BCC was made. On immunohistochemical examination, the tumour cells were Ber-EP4, cytokeratin AE1/AE3 and cytokeratin CAM 5.2 positive but S100 protein negative. Only the granular cells were CD68 antigen (monoclonal antibody KP1) positive.     

Granular cell basal cell carcinoma

Granular cell basal cell carcinoma (BCC) is a rare histologic variant of BCC. In this, the third reported case, the tumor consisted almost entirely of granular cells. By electron microscopy, these cells were filled with pleomorphic lysosome-like granules lined by unit membranes and containing homogeneous or granular electron-dense bodies, membranous debris and amorphous material. The epithelial origin of the tumor was suggested by the characteristic light microscopic appearance of tumor cell islands with some areas of peripheral palisading, and was confirmed by electron microscopic features of numerous well-formed pentalaminate desmosome junctions and sparse cytoplasmic tonofilament bundles, some of which showed attachments to the desmosomes. Histochemical immunoperoxidase stains for lysozyme showed no cytoplasmic lysozyme activity, in common with other granular cell tumors, but ultrastructural examination did not reveal angulate bodies, in contrast to findings in non-epithelial granular cell tumors.     

皮肤透明细胞鳞状细胞癌

报告1例面部透明细胞鳞状细胞癌.患者女,90岁.左面颊新生物伴溃疡半年余.组织病理检查示:癌细胞呈巢状,细胞多角形,胞质透明,核明显异形.皮损组织病理检查证实为透明细胞鳞状细胞癌.     

Basal cell carcinoma: cell of origin, cancer stem cell hypothesis and stem cell markers

Cancer stem cells have recently been described in several high-grade neoplasms. It is still unclear if they also occur in cutaneous malignancies. Cancer stem cells are not identical with somatic stem cells. The presence of tumour stem cells in a neoplasm does not in itself equal that the tumour derives from a somatic stem cell. A cell originally lacking stem cell characteristics could also acquire those features during the course of carcinogenesis and then becomes the clonal founder cell of a tumour. Basal cell carcinoma (BCC) is the most common cutaneous malignancy. A plethora of various stem cell markers has been applied to study its cellular origin. Intriguingly, the anatomical origin of BCC is still uncertain. This review will discuss the various stem cell markers used in BCC and the cellular origin of this tumour, and touches briefly on the possibility of cancer stem cells in BCC. If BCC or other skin cancers harbour tumour stem cells, these cells could be specifically targeted, making use of specific cell surface molecules such as receptor proteins. Novel drugs directed against those receptor proteins could replace currently available shotgun approaches including imiquimod.     

Insights into the Merkel cell phenotype from Merkel cell carcinoma cell lines

Merkel cell carcinoma (MCC) of the skin is an aggressive form of skin cancer and is being seen with increasing incidence in Queensland. We have recently established a number of MCC cell lines and characterized these for growth, morphology, expression of neuroendocrine markers and radiation sensitivity. As a result, cell lines were grouped into four classes by their morphology in a similar way to small cell lung cancer (SCLC) cell lines. Types I and II cell lines grew slowly as tight spherical clusters suspended in the medium, with Type II cell lines less densely packed than the Type I cell lines. Type III cell lines grew as flat 2-dimensional clusters and had shorter doubling times and Type IV cell lines grew as adherent monolayers and had the shortest doubling times. Expression of neuroendocrine markers distinguished those with a classic phenotype from those with a variant one. Mainly morphological Types I and II retained the classic phenotype while Classes III and IV had a variant phenotype. The range of surviving fraction at 2 Gray (SF2 0.2-0.45) seen in MCC cell lines was not as high as seen in SCLC cell lines but the variant ones tended to be more radiation resistant. Examination of POU proteins showed that neuroendocrine phenotype was linked with expression of brn-2, and growth in suspension with brn-3c.     

Telomerase activity of Merkel cell carcinomas and Merkel cell carcinoma-derived cell cultures

Abstract Merkel cell carcinomas are rare malignant tumors of the skin, which are predominantly observed in elderly patients (mean age 65–70 years). It is believed but not yet proven that these tumors are derived from the Merkel cells of the epidermis and hair follicles. The Merkel cells themselves probably originate from an asymmetric cell division of basal keratinocytes and the resulting differentiated Merkel cells have presumably, at least in humans, lost their growth potential. The capability of indefinite cell division in germ line cells and in the great majority of malignant tumors as well as an increased growth potential in certain somatic cells (such as basal cells of renewable tissues) is correlated with cellular telomerase activity, which is absent in differentiated somatic cells. In this study the telomerase activity in cryostat sections of frozen Merkel cell tumor biopsies and in in vitro cultivated Merkel cell carcinoma cells was analyzed. We detected telomerase activity in four tumors and three of four cell cultures. These results show that despite their pronounced neuroendocrine differentiation and their occurrence in patients of advanced age, Merkel cell carcinomas possess telomerase activity similar to that of common carcinoma types. Received: 18 October 2000 / Revised: 3 February 2001 / Accepted: 27 April 2001     

Signet ring cell basal cell carcinoma.

A 63-year-old man presented with a signet ring cell basal cell carcinoma of the right infraorbital area. This is the third reported case of this rare variant of basal cell carcinoma characterized by tumor cells containing large, hyalinized, eccentric, intracytoplasmic inclusions that compress nuclei into crescent or ring-shaped forms. Antibodies to both high and low molecular weight cytokeratins were strongly positive, staining the inclusions in a uniform fashion. Vimentin and actin antibodies did not stain the inclusions. These results support previous electron microscopic studies that show the inclusions to be aggregates of intermediate filaments blending into tonofilaments at their periphery. Although speculative, the formation of signet ring cells does not appear to be a degenerative or necrotic phenomenon, but probably a peculiar aberrant form of individual cell keratinization.     

Shadow cell basal cell carcinoma with acantholysis

I present histologic documentation of a unique basal cell carcinoma (BCC) in which shadow cells formed the major cellular component along with extensive acantholysis and the development of ringed shadow cells. This neoplasm contained trichohyalin granules, which are indisputable evidence of follicular differentiation. Shadow cells rarely are encountered within BCCs and generally form relatively small components. Such neoplasms have been labeled BCC with matrical differentiation. Because of nonspecificity and ambiguity, I propose that this terminology be abandoned and replaced by shadow cell BCC.     

Cutaneous indeterminate cell histiocytosis: a new spindle cell variant resembling dendritic cell sarcoma

BACKGROUND: Cutaneous indeterminate cell histiocytosis is a rare neoplastic disorder. Its varied histological presentation and rarity have limited efforts to determine its pathogenic relationship with other histiocytic lesions and possibly, its recognition. METHODS: We report on an unusual histologic pattern of indeterminate cell histiocytosis that resembled follicular dendritic sarcoma. A battery of immunohistochemical stains and electron microscopy were performed to elucidate the phenotype of the "histiocytic" cells. Based on a review of the literature, reported cases of indeterminate cell histiocytosis are presented and the diagnostic differential of spindle-cell lesions is discussed. RESULTS: Spindling histiocytes were positive for S-100 and CD1a. The monocytic/macrophage marker, CD68, and the dendritic cell marker, CD21, were negative. Electron microscopy failed to reveal Birbeck granules. CONCLUSIONS: Relatively few reports of indeterminate cell histiocytosis exist, some of which include discussion of potential overlaps with the non-X histiocytoses. Although the presence of prominent spindling in our case expanded the differential to include non-histiocytic disorders, the identified histiocytes unequivocally fulfilled the criteria of S-100 and CD1a positivity without demonstrable Birbeck granules.     

Cutaneous spindle cell carcinoma following basal cell carcinoma

A spindle cell carcinoma arose three years after the seeming excision of a so-called "infiltrative" basal cell carcinoma (IBCC) in the cheek of an 87-year-old Japanese woman. The patent had no history of irradiation. The tumor was composed of short fascicles and whorling arrangements of spindle to polygonal cells without residual IBCC. Immunohistochemically, the tumor was positive for vimentin, cytokeratin 8 & 18, epithelial membrane antigen, and alpha-smooth muscle actin. Ultrastructurally, the tumor cells had tonofilaments and desmosomes. The patient died after a local recurrence with metastatic lesions in the lung and the neck lymph nodes that were indicated by CT scanning and MRI at nine months after diagnosis. This case and others support the concept that spindle cell carcinoma can pursue an aggressive clinical course.     

Multiple basal cell carcinomas associated with hairy cell leukaemia

We report the case of a caucasian woman who, between the ages of 49 and 51 years, developed multiple (> 20) basal cell carcinomas (BCC). There was no family history of BCC. No abnormalities in the human homologue of the Drosophila segment polarity gene patched (PTCH), glutathione S-transferases T1 and M1, or cytochrome P450 1A1 were detected by polymerase chain reaction (PCR)-based molecular analysis. There was, however, actinic damage of the skin in sun-exposed areas. The patient was diagnosed as having hairy cell leukaemia (HCL) at the age of 51 years, based upon leucocyte morphology as assessed by light and electron microscopy, tartrate-resistant acid leucocyte phosphatase (TRAP) staining, fluorescence activated cell scanning of peripheral blood leucocytes and bone marrow histology. As the leukaemia slowly progressed over a 3-month period, the patient developed four further BCCs. Given that HCL is characterized by a profound defect in T-cell function, it is conceivable that T-cell immune dysregulation can contribute to the pathogenesis of BCC, possibly enhancing the aetiological effect of ultraviolet irradiation.     

Granular cell basal cell carcinoma: A case report

Granular cell basal cell carcinoma (BCC) is a rare histopathological variant of BCC. Our review of the literature revealed only 17 previously identified cases. We report the case of a 47‐year‐old man who presented with an ulceration on his right upper lip which was subsequently removed. Histopathologic examination revealed that the tumor was composed solely of granular cells with numerous cytoplasmic eosinophilic round inclusion bodies. Mitotic figures ranged from 8 to 15 per 10 high‐power fields, with a Ki‐67 proliferative index of ~5%. Immunohistochemically, the granular cells showed strong and diffuse positivity for Ber‐EP4, pan‐cytokeratin, AE1/AE3, CK5/6 and p63 and focal positivity for lysozyme, CD68 (clone KP1) and Bcl‐2.     

Signet ring cell basal cell carcinoma: a basal cell carcinoma with myoepithelial differentiation.

Basal cell carcinoma (BCC) can show a variety of routes of differentiation, but myoepithelial differentiation has rarely been described. We describe a case of BCC showing histologic and immunohistochemical features of myoepithelial differentiation. Histologically, the lesion showed well-demarcated tumor nodules composed of two different components. One component was typical of BCC, and the other component was composed of tumor cells containing abundant cytoplasm, eccentric nuclei, and no peripheral palisading, with scattered signet ring-shaped cells. Immunohistochemically, the tumor cells in the typical BCC component stained with CKAE1/AE3 and smooth muscle actin (SMA), but not with S-100 protein. They stained weakly with CAM5.2, epithelial membrane antigen, and glial fibrillary acidic protein (GFAP). The tumor cells in the other component stained strongly with CKAE1/AE3 and SMA, moderately with epithelial membrane antigen and GFAP, and weakly with CAM5.2. In a small area, the tumor cells stained with S-100 protein.