Acral cutaneous melanoma in caucasians: clinical features, histopathology and prognosis in 112 patients.

BACKGROUND: Acral lentiginous melanoma (ALM) is the fourth distinct variant of cutaneous melanoma. The histological diagnosis and prognosis of ALM are still controversial. OBJECTIVES: To review the features of a large series of patients with ALM, and confirm the validity of the histological criteria for this type of melanoma. METHODS: A collection of 2642 patients with cutaneous melanoma was recorded during the period 1986-97, among these 187 were located on acral sites. Histological specimens were reviewed in 112 acral melanomas; the following study is based on this subgroup. RESULTS: Histological examination revealed acral lentiginous melanomas predominantly in palmoplantar and subungual locations (60%), while superficial spreading melanomas (SSM) were found mainly on the dorsal aspects of hands and feet (30%). Nodular melanomas (NM) (9%) occurred in all acral sites. The histological re-examination confirmed the characteristics of ALM as described by Reed in 1976. With increasing tumour thickness nesting of tumour cells and upward migration to the cornified layer was similarly observed. The 5-year survival rate for patients with primary acral melanoma without recognizable metastasis was 82%. ALM differed significantly in survival from SSM (P = 0.001) and lentigo maligna melanoma (P < 0. 001), but survival rates were similar to NM (P = 0.9). CONCLUSIONS: ALM, as diagnosed by current histological criteria, occur on the palms, soles and subungual sites, and have a poor prognosis.

Melanocytes in nevi and melanomas synthesize basement membrane and basement membrane-like material. An immunohistochemical and electron microscopic study including immunoelectron microscopy.

Light microscopic studies have shown that nevus cell nests and melanoma nests are surrounded by basement membrane (BM) material containing type IV collagen and laminin. This study confirms this by electron microscopy and relates it to proteins which interact with the basement membrane. Nevi except for dysplastic and Spitz nevi, malignant melanomas, and melanoma metastases were studied by immunohistopathology, routine electron microscopy (EM), and immunoelectron microscopy. The lesions were incubated with monoclonal antibody (moAb) against type IV collagen, laminin, and the integrin alpha6 and studied by light microscopy. In addition, melanomas were studied by immuno-EM after incubation with a moAb against matrix metalloproteinase-2 (MMP-2). Nevus cell nests and melanoma nests are surrounded by BM material containing type IV collagen and laminin by immuno-EM. The BM material various in thickness and is amorphous. Type IV collagen, laminin, and MMP-2 are synthesized by melanoma cells as well as adjacent fibroblasts. Destruction or loss of the BM is not mandatory for melanoma invasion or even metastasis. Possibly the BM material is a protective wall for melanoma cells. Interactions between melanocytes and the extracellular matrix of which the BM is a part, can be traced back to the migration of melanocytes from the neural crest.

Human melanoma progression in skin reconstructs : biological significance of bFGF.

Human skin reconstructs are three-dimensional in vitro models consisting of epidermal keratinocytes plated onto fibroblast-contracted collagen gels. Cells in skin reconstructs more closely recapitulate the in situ phenotype than do cells in monolayer culture. Normal melanocytes in skin reconstructs remained singly distributed at the basement membrane which separated the epidermis from the dermis. Cell lines derived from biologically early primary melanomas of the radial growth phase proliferated in the epidermis and the basement membrane was left intact. Growth and migration of the radial growth phase melanoma cells in the dermal reconstruct and tumorigenicity in vivo were only observed when cells were transduced with the basic fibroblast growth factor gene, a major autocrine growth stimulator for melanomas. Primary melanoma cell lines representing the more advanced stage vertical growth phase invaded the dermis in reconstructs and only an irregular basement membrane was formed. Metastatic melanoma cells rapidly proliferated and aggressively invaded deep into the dermis, with each cell line showing typical invasion and growth characteristics. Our results demonstrate that the growth patterns of melanoma cells in skin reconstructs closely correspond to those in situ and that basic fibroblast growth factor is critical for progression.

Patterns of local horizontal spread of melanomas: consequences for surgery and histopathologic investigation.

Understanding local spreading patterns of melanomas is a precondition for the localized surgical treatment and histopathologic investigation. We used hematoxylin and eosin-stained paraffin sections for a two-phase, cellular and microscopic study of patterns of lateral spread in superficial spreading melanomas (SSMs), nodular melanomas (NMs), lentigo maligna melanomas (LMMs), and acral lentiginous melanomas (ALMs). Complete histologic examination of vertical excisional margins was carried out with paraffin sections 5 mm beyond the clinical tumor border of 1395 SSMs, 376 NMs, 179 LMMs, 46 ALMs, and 37 acrally located SSMs or NMs. Further sections of embedded material were analyzed when tumor-positive margins were found. In case of continuous tumor spread, reoperations were continued until the tissue was free of tumor cells. In case of noncontinuity, a final excision was made to a minimum safety margin of 10 to 20 mm. Concentrically consecutive, 5-microm thick hematoxylin and eosin-stained sections were taken from the outside of a 10-mm safety margin inward to the clinical borders of 34 SSMs, five NMs, 10 LMMs, and five ALMs. Noncontinuous subclinical spread was found in all SSMs and NMs in the form of few isolated cell nests at the epidermis-dermis junction. Ninety-two percent of these were located within 6 mm of the central tumor. All LMMs and ALMs showed a clearly demonstrable, uninterrupted spread into the periphery at the epidermis-dermis junction, too, usually in groups of outgrowths. The probability of finding these outgrowths 5 mm beyond the clinical tumor border was 54% in LMM and ALM. Complete histologic examination of vertical excisional margins (micrographic surgery) is therefore the therapy of choice only for LMM and ALM and is inefficient for SSM and NM.

Ultrastructural localization of alpha-3 integrin subunit in malignant melanoma and adjacent epidermis.

Eight cases of malignant melanoma were studied by immunohistopathology and immunoelectron microscopy. Alpha3 integrin localization was documented in malignant melanoma cells, basal and suprabasal keratinocytes, melanocytes, blood vessels and in basement membrane material. In melanoma cell membranes and, to a lesser extent, the interior of melanosomal vesicles were labeled. In addition, neighbouring cells such as basal and suprabasal keratinocytes and melanocytes showed strong alpha3-integrin expression. The labeling was much stronger in the plasma membrane than in the cytoplasm. Endothelial cells showed stronger labeling of the cytoplasm than of the plasma membrane. In some cases we found increased flocculent material surrounding melanoma cells or nests that seems to contain basement membrane protein components, specifically alpha3-integrin subunits. Compared to normal epidermis alpha3-labeling was stronger in tissues of malignant melanoma.

Update on immunoelectron microscopy in diagnostic dermatopathology and cutaneous biology.

Immunoelectron microscopy for diagnostic dermatopathology is hardly ever necessary. Immunoelectron microscopy, however, is very helpful in the work-up of interesting cases, for the study of genetic and autoimmune bullous diseases and for basic science studies, particularly in conjunction with molecular biology techniques. It is also very helpful for investigators requiring double labeling.

Granulomatous mycosis fungoides: report of a case with some histopathologic features of granulomatous slack skin.

We describe a case of granulomatous mycosis fungoides, tumor stage, mimicking sarcoidosis in an 82-year-old man with a 2-year history of skin disease. The final diagnosis was established after one of seven biopsy specimens showed a nongranulomatous histologic picture of patch-stage mycosis fungoides. Monoclonality was proven for the lymphocytic population by T-cell-receptor rearrangement studies. The unusually extensive granulomatous inflammation with huge giant cells surrounded by CD1a-positive cells in the other six biopsy specimens was suggestive of the histopathology of granulomatous slack skin, another rare granulomatous cutaneous T-cell lymphoma. Because both a clinical and histologic overlap between granulomatous mycosis fungoides and granulomatous slack skin have been reported in the literature, we conclude that they may belong to the spectrum of a single disease.

[Desmoplastic squamous epithelial carcinoma of the skin and lower lip. A morphologic entity with great risk of metastasis and recurrence]. / Das desmoplastische Plattenepithelkarzinom der Haut und Unterlippe. Eine morphologische Entität mit hohem Metastasierungs- und Rezidivierungsrisiko.

The desmoplastic type of the squamous cell carcinoma (DSCC) of the skin is an entity which is readily distinguished by light microscopy. The DSCC has fine branches surrounded by a desmoplastic stroma and shows in some cases typical perineural, perivascular and widespread intradermal invasion (maximum 6 cm!). This type accounts for 8.2% (n = 44) of our collective of 594 squamous cell carcinomas (SCC) of the skin and vermilion border. Clinically DSCC look like other malignant epithelial tumors of the skin. All tumors were followed up for at least 3 years (maximum 10 years). The local recurrence rate was high (24.3%) even though micrographic surgery was carried out. The rate of local or regional metastasis was also very high (22.7%). In comparison the recurrence rate and the rate of metastasis of the remaining common 91.8% SCC's (n = 550) was low: 2.6% and 3.8%, respectively. The DSCC seems to be identical with the so called neurotropic SCC, the fine stranded SCC or the SCC with perineural invasion which have a high rate of local recurrence and metastasis as well, but DSCC is a better generic histopathologic term for the entire group. The DSCC is best treated with micrographic surgery and wider safety margins than any other type and should be followed up very frequently.

[Scleredema adultorum Buschke. Case report and review of the literature]. / Scleroedema adultorum Buschke. Fallbericht und Literaturübersicht.

Scleredema adultorum of Buschke is a rare disorder of unknown aetiology. It is characterized by diffuse, non-pitting swelling and induration of the skin. Skin biopsies reveal marked thickening of the dermis due to collagenous replacement of the subcutis and deposition of hyaluronic acid between the collagen fibers. The disease classically only affects the skin. In 24 cases an associated monoclonal gammopathy has been detected. A 75-year-old patient had a 19-year history of scleredema adultorum. In addition to a monoclonal gammopathy the patient suffered from involvement of the tongue, pharynx and upper esophagus. Furthermore a polyneuropathy, ocular involvement with restricted eye movements and a sicca syndrome were present. The simultaneous occurrence of cutaneous scleredema with any one of the above mentioned symptoms has been reported before. The wide variety of extracutaneous manifestations of scleredema as found in our patient is amazing and has not been previously described.

Desmoplastic squamous cell carcinoma of skin and vermilion surface: a highly malignant subtype of skin cancer.

BACKGROUND: The prognosis of squamous cell carcinoma (SCC) of the skin is directly related to the development of metastases or local recurrence. This is affected by numerous factors, most of which are independent: clinical tumor size, histopathologic tumor thickness, depth of penetration, degree of cell differentiation, degree of keratinization, location, and immunosuppression. The determination of whether desmoplasia, previously described in only one case of SCC, constitutes an additional prognostic factor was the objective of this study. METHODS: The study was performed prospectively on 594 SCCs from 509 patients. All of the factors mentioned earlier were present. Forty-four SCCs were identified by light microscopy as desmoplastic due to their prominent trabecular growth patterns, narrow columns of atypical epithelial cells, and marked desmoplastic stromal reaction, in some cases with perineural and perivascular invasion. Follow-up ranged from 4 to 10 years (median, 5.3 years). RESULTS: All tumors in the study patient population were treated using the paraffin section method of micrographic surgery. The 44 desmoplastic SCCs were found to metastasize 6 times more often than the remaining 550 tumors (22.7% vs. 3.8%), with 10 times as many local recurrences (27.3% vs. 2.6%). CONCLUSIONS: Desmoplasia is a highly significant (P < 0.001) prognostic factor for SCCs and is associated with the development of metastases or recurrence.

Immunohistochemical localization of muscarinic acetylcholine receptors in primary and metastatic malignant melanomas.

In embryos morphogenetically active cells transiently express the cholinergic system comprising cholinesterase activity and muscarinic acetylcholine receptors. Malignant melanomas develop from melanocytes, which are derived from the neural crest. Neural crest cells express the embryonic muscarinic system during migration. Using the monoclonal antibody M35, we now show that normal melanocytes carry no muscarinic receptors, whereas malignant melanoma cells express them again. In primary melanomas and metastatic melanomas, we identified muscarinic receptors in solid strands or groups of atypical cells. In all primary malignant melanomas studied we found inhomogeneous distributions of M35-immunoreactivity subdividing the tumors into three different zones. In the tumor center, groups or single cells often showed only little or even no immunofluorescence. In contrast, pericentrally we detected strong immunostaining in the conglomerations of atypical melanocytes. In the peripheral infiltration zone, intensely fluorescent cells in clusters or single, were spreading into the normal tissue, leading to a more patchy staining pattern. Melanocytes of nevi also possess muscarinic receptors, showing similar distribution patterns as in the melanoma. We suggest that in malignant melanomas muscarinic receptors might play a regulative role in infiltrative growth and metastasis.

Detection of Borrelia burgdorferi DNA (B garinii or B afzelii) in morphea and lichen sclerosus et atrophicus tissues of German and Japanese but not of US patients.

OBJECTIVE: To elucidate the geographic and genospecific association of Borrelia with morphea and lichen sclerosus et atrophicus (LSA). DESIGN: The association of Borrelia burgdorferi with morphea and LSA has been reported, but is still controversial. We conducted a retrospective survey of Borrelia DNA in skin biopsy specimens. SETTINGS: The samples were collected from the outpatient clinic of university hospitals and a dermatopathology laboratory. PATIENTS: Skin biopsy specimens (19 morphea and 34 LSA) were obtained from patients in the United States, Japan, and Germany. DNA samples were subjected to amplification with polymerase chain reaction for B burgdorferi flagellin gene, and for the genotype-specific detection of B burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii. RESULTS: Five cases of morphea and 2 cases of LSA in Germany and Japan yielded positive signals for B garinii or B afzelii, the European species. None of the American samples were positive for Borrelia polymerase chain reaction. Borrelia burgdorferi sensu stricto was not detected in any of the specimens. CONCLUSION: Morphea and LSA in Germany and Japan can be related with European genotypes of Borrelia.

[Amelanotic melanoma of the vulva simulating lichen sclerosus et atrophicus]. / Amelanotisches Melanom der Vulva unter dem klinischen Bild eines "Lichen sclerosus et atrophicus".

Malignant melanoma of the vulva is an uncommon disease. The amelanotic subtype is only rarely mentioned. We report a 60-year-old patient with a 6 month history of vulvar pruritus. Ivory lesions combined with erosions and fine "cigarette paper'-like wrinkling were suspicious for lichen sclerosus et atrophicus. Histologically the diagnosis of an amelanotic malignant melanoma was made. Amelanotic melanoma may present with a wide variety of clinical features. Even in the uncommon location of the vulva, amelanotic melanoma should be suspected in any nonhealing nonpigmented lesion.

Malignant chondroid syringoma: immunohistopathology.

Malignant chondroid syringoma, also called malignant mixed tumor of the skin, is a rare variant of a malignant tumor derived from sweat gland cells. Histologically the tumor is composed of an epithelial and a mesenchymal component. The epithelial structures show glandular differentiation and carcinomatous features. They are embedded in a mucinous stroma with spindle mesenchymal cells and areas of chondroid differentiation. The epithelial cells express cytokeratins. The luminal epithelial cells show binding to the lectin Ulex europaeus; intraluminal cells are carcinoembryonic antigen positive. The stromal cells are cytokeratin negative and sporadically positive for vimentin. Chondroid areas are S-100 protein and vimentin positive. No labeling for actin is seen.

Amelanotic malignant melanoma of the vulva. Case report and review of the literature.

We report on a 60 year old patient with a 6 month history of vulval pruritus and an erosive vulval lesion which was mistaken for lichen sclerosus et atrophicus. Histologically the diagnosis of an amelanotic malignant melanoma of the vulva was established. We review the literature about this rare malignant tumor.

New applications of electron microscopy techniques in dermatopathology.

The application of immunostaining techniques to electron microscopy specimens has led to a renewal of interest in electron microscopy in biological research in general, as well as in dermatopathology. Refinements in the preparative procedures have made easier the immunolocalization of antigens both in chemically-fixed and frozen unfixed tissues, embedded in plastic and sectioned. Application of these methods has led to the demonstration of the bullous pemphigoid antigen inside basal keratinocytes. HMB-45 antigen has been found to be present in premelanosomes. Recently, Factor XIIIa has been localized not only in dermal dendrocytes but also in endothelial cells and mast cells.

Immunocytochemical and immunoelectron microscopic demonstration of cathepsin B in human malignant melanoma.

Proteases are known to enhance the spread of tumour cells. Possible sources of these proteases are the tumour cells themselves or fibroblasts in the tumour tissue. Immunological staining with anticathepsin B antibody indicates that the subcellular distribution of cathepsin B in tumour cell lines differs from that in normal liver. The aims of this study were: (i) to show whether different types of melanoma differ in their production of cathepsin B; (ii) to identify the cathepsin B-producing cells; and (iii) to determine the subcellular distribution of cathepsin B in melanoma cells. All types of melanomas contained cell regions stained with anticathepsin B antibody. The intensity of the stain and the number of cells reacting with anticathepsin B antibody depended on the size of the tumour but not on the type of melanoma. Epithelioid cells stained more intensely with anticathepsin B antibody than spindle-shaped cells. Cells staining with anticathepsin B antibody were almost exclusively tumour cells. Anticathepsin B stain was located mainly in vesicular structures which did not contain a filamentous matrix. Additional anticathepsin B stain was detected at the extracellular spaces. Hypomelanotic melanoma cells, mainly of the epithelioid type, produced most of the cathepsin B. Cathepsin B may be involved in both the degradation of possibly abnormal melanosomes and the focal degradation of the extracellular matrix.

Langerhans' cells in skin tumors.

DESIGN: We studied 58 skin specimens of normal skin (NS), basal cell epithelioma, squamous cell carcinoma, seborrheic keratosis, and malignant melanoma for the presence of Langerhans' cells (LCs) in and above the tumor. Anti-CD1 was used as a marker for LCs. All specimens were also incubated with anti-CD4, which also labels a certain number of LCs. RESULTS: All tumors contained LCs in the tumor and overlying epidermis. The number of LCs over basal cell carcinoma, squamous cell carcinoma, and malignant melanoma was significantly lower than in normal skin and seborrheic keratosis. These results are presented in detail and are compared with former studies discussing the different methodological approaches. CONCLUSIONS: Langerhans' cells were present in the epidermis of all the examined tumors. A certain percentage of LCs express CD4 surface antigen. This percentage varies from tumor to tumor.

Angiomyolipoma of the kidney. Immunoreactivity with HMB-45. Light- and electron-microscopic findings.

Immunoreactivity with HMB-45 has recently been described in renal angiomyolipoma, a tumour of smooth muscle cells. HMB-45 is a monoclonal antibody that reacts specifically with melanosomes. In order to determine whether the tumour cells contain melanosomes and synthesize melanin, seven tumours were studied by light microscopy and immunohistochemically with the antibodies HMB-45, KP1 (CD68), PG-M1 (CD68), Ki-M1P, anti-lysozyme, anti-smooth-muscle actin, anti-vimentin, anti-S100 protein and KL1 (anti-keratin). Two tumours were also studied by electronmicroscopy and one by immuno-electronmicroscopy. Histochemical investigation for dopa oxidase was performed on cryostat sections. The tumours contained varying numbers of HMB-45-positive muscle cells. Reactivity was noted in lysosomal granules and rough endoplasmic reticulum. Typical premelanosomes were found in the tumour cells by electronmicroscopy. Groups of tumour cells stained for dopa oxidase. The tumour cells were not reactive for lysozyme, but reacted with KP1, PG-M1 and Ki-M1P. Immuno-electronmicroscopy showed that reactivity for KP1 was located within lysosomal granules. The findings show that the tumour cells of renal angiomyolipoma contain premelanosomes and that they are able to synthesize melanin, because they contain dopa oxidase. Immunoreactivity with KP1, PG-M1 and Ki-M1P can be attributed, in the absence of staining for lysozyme, to the large number of lysosomal granules. The tumour cells were not found to be related to macrophages or myeloid cells.

Ultrastructural localization of factor XIIIa.

Thin sections of dermatofibromas, of a basal cell epithelioma, a patch stage lesion of Kaposi's sarcoma, a case of angiolymphoid hyperplasia with eosinophilia, and one case of malignant mastocytosis were incubated with antibody to factor XIIIa (FXIIIa). Regardless whether the tissue had been embedded in Lowicryl K4M, Epon, or Araldite, labeling was found in dermal dendrocytes, mast cells, and endothelial cells. In dermal dendrocytes, the reaction product was seen in dilated cisternae of the rough endoplasmic reticulum as well as free within the cytoplasm. In endothelial cells, FXIIIa was localized within Weibel Palade bodies, free within the cytoplasm, and in villous projections into the vasucular lumen. In mast cells, the reaction was found in mast cell granules exclusively. Mast cells, dermal dendrocytes, and endothelial cells have in common that all three express FXIIIa, belong to the microvascular unit, and are increased in number during angiogenesis and in fibrovascular processes. It thus seems that these cells are functionally related.