Malignant epidermal tumours

Clinicopathologic and immunohistochemical features of pigmented Basal cell carcinomas of the eyelids

PURPOSE

To describe the clinical and microscopic features of pigmented basal cell carcinomas (pBCC) of the eyelid.

DESIGN

Retrospective observational case series collected at one institution.

METHODS

An analysis of clinical records, photographs, and histopathologic characteristics of 257 BCCs with a review of the literature. The frequencies of clinically pigmented, and of microscopically pigmented but clinically nonpigmented, BCCs were determined. Cytochemical stains (Fontana-Masson, Prussian blue) and immunohistochemical probes (S-100, microphthalmia-associated transcription factor [MiTF], HMB-45, MART-1, CK20, synaptophysin, chromogranin, CD1a, Ki-67) were then employed and the findings correlated with the degree of clinical pigmentation.

RESULTS

Histopathologically, 13 of 257 cases (5.06%) were found to have pigment; of these 13, 6 (all white patients) had clinically apparent pigmentation (2.33%), either focal or diffuse. Eight of 13 lesions developed on the lower eyelids. All stained positively for melanin but negatively for iron. MiTF highlighted numerous melanocytic nuclei in the tumor lobules, while MART-1 and HMB-45 revealed the dendritic shapes of the entrapped melanocytes. There was a subtotal blockage of melanin transfer to the surrounding basaloid cells. Intralobular S-100-positive cells included CD1a-positive Langerhans cells, while CK20 did not identify any Merkel cells.

CONCLUSIONS

Only 1 of 6 lesions was uniformly clinically pigmented, whereas the other 5 were only focally brown-black. The clinical pigmentation was imparted by varying densities and distributions of melanocytes with arborizing dendrites, which were present in all BCCs. Melanophages within the stroma and basaloid cell melanization also contributed to pigmentation. No behavioral or biologic differences in pBCC were documented compared with clinically nonpigmented lesions.

Selected Pseudoneoplastic Lesions of the Skin

Context.—Pseudoneoplastic cutaneous lesions are diverse, not only morphologically but also with respect to their causes and cellular lineages. They include proliferations of epithelial, as well as mesenchymal, elements.

Objective.—This review aims to consider selected lesions in the aforementioned groups, contrasting them with histologically similar neoplasms of the skin in a differential diagnostic setting.

Data Sources.—Information used in assembling this discussion was drawn from the published literature on cutaneous pseudoneoplasms, using an Internet-based search engine. The authors' collective experience was also used in writing this review.

Conclusions.—Sufficient clinical and morphologic differences exist in virtually all instances to separate pseudoneoplastic cutaneous proliferations from the tumors that they imitate.

The gene for multiple familial trichoepithelioma maps to chromosome 9p21

Multiple familial trichoepithelioma (MFT) is an autosomal dominant skin disease characterized by the presence of many small tumors predominantly on the face. To map the causative gene, we performed linkage analysis with microsatellite markers in three American families. We found a significant linkage of a gene for MFT to chromosome 9p2l. The maximum combined lod score was 3.31 at D9S171 at theta = 0. The disease locus was defined to a 4-cM region between IFNA and D9S126. Because several tumor suppressor genes including p16 and p15 have been mapped to this region, the gene for MFT may also be a tumor suppressor.

Risk factors related to locoregional recurrence in squamous cell carcinoma of the skin

A retrospective analysis was performed to identify the risk factors associated with development of locoregional recurrent disease in patients with primary squamous cell carcinoma of the skin. Step-wise logistic regression analysis was used in this study, which consisted of 1,039 patients treated from January 1980 to December 1989 at Ankara Oncology Hospital. Locoregional recurrence occurred in 187 (18%) of these patients within a mean disease-free period of 15 months. Age, sex, anatomical location, size of lesion, lymph node, status at diagnosis, stage according to TNM classification, histopathologic grade, previous therapy, treatment modality, lesions arising from scar tissue (scar carcinoma), regional lymph node dissection, concomitant premalignant tumor of the skin, development secondary nonmelanotic skin carcinoma, and second malignancy were used as variables that could be correlated with locoregional recurrent disease. No correlation was found between development of recurrence and previous therapy, second nonmelanoma skin cancer, second malignancy, premalignant skin tumor, sex, or regional lymph node dissection. Although univariate analysis demonstrated that location, tumor size, patient's age, lymph node status, stage, histopathologic grade, scar carcinoma, and treatment modality were associated with an increased risk of locoregional recurrence, it was found that stage of the disease (P < 0.001), treatment modality (P < 0.01), tumor arising from scar tissue (P < 0.01), and histopathologic grade (P < 0.05) were statistically significant as risk factors of recurrence when a multivariate analysis was applied.

Eccrine differentiation in basal cell carcinoma

Eccrine differentiation according to histologic and immunohistochemical criteria was demonstrated in 16 of 66 basal cell carcinomas. The possibility of origin of these neoplasms from the eccrine duct, including the acrosyringium, is discussed in relation to the differences in site distribution and etiology between basal cell carcinoma and squamous cell carcinoma.

The histopathology of the skin basal cell carcinoma with areas of intermediate differentiation. A metatypical carcinoma?

The histopathology of the skin basal cell carcinomas (BCCs) with areas of intermediate differentiation (ID) has been investigated. In a series of 127 BCCs, areas of ID were found in 28 tumors (22%), and also in an additional 10 cases of other series. These areas consisted of compact masses of cells without peripheral palisading, and with intermediate differentiation between basal and squamous cells. In comparison with the common undifferentiated BCCs, the BCCs with the ID areas may behave in a more aggressive fashion, since they displayed more precocious ulceration in small tumors (p less than 0.001), greater infiltrative features (p less than 0.001), more atypical cells (p less than 0.001) with increased nuclear-cytoplasmic ratio and more mitoses (p less than 0.001). The relation of such basal cell carcinomas to the metatypical carcinoma of the skin was discussed. Metatypical carcinoma, however, has been poorly defined and thus has no general acceptance in the literature. The new definition of the basosquamous cell carcinoma and the presence of intermediate areas of differentiation in this tumor were emphasized, and it was suggested that metastatic basal cell carcinoma and metatypical carcinoma may be the same tumor.

The epidermal basement membrane in basal cell carcinoma: an immunohistochemical study

An immunohistochemical study of basal cell carcinomas of varying histological type, using a panel of antibodies to constituents of the epidermal basement membrane, showed marked deficiencies in the expression of the antigens identified by the antibodies LH7.2, GB3 and G71. There was no correlation between loss of immunoreactivity to these antibodies and the histological features of the tumour.

Clear cell basal cell carcinoma

We describe a case of clear cell basal cell carcinoma of the superficial type, presenting as a crusted eruption on the abdomen. Histological examination showed a solid proliferation of clear cells attached to the under-surface of an atrophied epidermis. In addition, distinct pagetoid infiltration was seen within the overlying epidermis. A focal connection between the clear cell portion and a deeper lying nodular basal cell carcinoma was demonstrated, elucidating the true nature of the lesion. Immunohistochemical studies and electronmicroscopy confirmed the epithelial derivation of the tumour. The clear cell appearance was due to multiple cytoplasmic electronlucent vacuoles which were not surrounded by membranes.

Intralesional treatment of basal cell carcinoma with low-dose recombinant interferon gamma

In this pilot clinical trail the efficacy of intralesional low-dose human recombinant interferon-gamma was investigated in seven outpatients with nodular basal cell carcinoma. There was no antitumor response in any case. Toxic side effects were minimal. All tumors were excised surgically 8 weeks after completion of therapy.

An absence of human leukocyte antigen-DR and a decreased expression of beta 2-microglobulin on tumor cells of basal cell carcinoma: no influence on the peritumoral immune infiltrate

The expression of human leukocyte antigen-DR (HLA-DR) and beta 2-microglobulin on the tumor cells and their correlation (if any) to the degree and the composition of the peritumoral mononuclear infiltrate were studied in 37 basal cell carcinomas from 32 patients with an indirect immunoperoxidase technique. In 36 of 37 basal cell carcinomas (97%) there was no expression of HLA-DR on tumor cells of basal cell carcinoma. In 13 of 37 basal cell carcinomas (35%) beta 2-microglobulin was expressed on the tumor cells. Both a diffuse cytoplasmic and a membrane staining were observed in only six of these 13 basal a diffuse cytoplasmic and a membrane staining were observed in only six of these 13 basal cell carcinomas; in the other seven basal cell carcinomas only a diffuse cytoplasmic staining was observed. In all 37 basal cell carcinomas there was membrane staining for beta 2-microglobulin in the normal epidermis. The intensity of staining in the normal epidermis was always stronger than that in the tumor nests. There was a varying degree of peritumoral immune infiltrate in all basal cell carcinomas. It comprised mainly T cells (mean percentage 57 +/- 15). In the group of patients with basal cell carcinoma with moderate to heavy infiltrate the mean percentage of T cells was 63 +/- 13, which was significantly higher than the mean percentage of T cells (46% +/- 14%) in the group of patients with basal cell carcinoma with a mild infiltrate. This difference was mainly the result of an increase in T helper cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of the mononuclear infiltrate in basal cell carcinoma: a predominantly T cell-mediated immune response with minor participation of Leu-7+ (natural killer) cells and Leu-14+ (B) cells

We investigated the peritumoral inflammatory infiltrate in 22 basal cell carcinoma (BCC) from 18 patients using a series of monoclonal antibodies. In all the 22 BCC the infiltrate consisted mainly of T cells (55 +/- 15%) and only in three cases an invasion of the tumor nests by these cells was observed. The T helper (TH) subset predominated over the T suppressor/cytotoxic (TS/C) subset (TH/TS/C ratio of 1.9 +/- 0.8). In 8 of 22 BCC mild infiltrate was observed with 48 +/- 13% T cells and a TH/TS/C ratio of 1.5 +/- 0.6. In 14 of 22 BCC moderate to heavy infiltrate with 59 +/- 15% T cells and a TH/TS/C ratio of 2.0 +/- 1.0 was observed. There was a significant difference in the percentage of T cells in BCC with moderate to heavy infiltrate and that in BCC with mild infiltration. The mean percentage of HLA-DR+ cells was 54 +/- 11%; Langerhans cells (LC) 4 +/- 5%; and Leu-M5+ (monocytes and macrophages) 16 +/- 11%. Less than 2% Leu-14+(B) cells were seen in the infiltrate. The mean percentage of Leu-7+ (natural killer) cells was 4 +/- 4%, and only 1 of 22 BCC Leu-7+ cells invaded tumor nests, contacting with tumor cells. From these results we concluded that T cells play a major role in the defence against BCC proliferation. The main role of Langerhans cells and Leu-M5+ cells may be that of antigen presentation. B cells and NK cells probably play a minor role in the local defence against BCC proliferation.

Basosquamous cell carcinoma of the skin with metastases

Two cases of basosquamous cell carcinoma of the skin with lymph node, lung and bone metastases are reported. Metastases occurred 4 and 7 years after identification of the primary tumour. Both the primary and metastatic lesions had areas of typical basal cell carcinoma and squamous cell carcinoma and also intermediate carcinomatous tissue. In the bone metastasis of one case there were rudimentary hair follicles and areas of matrical differentiation. These cases further support the existence of basosquamous cell carcinoma and emphasize its metastatic potential.