Prognostic immunohistochemical markers of primary human melanomas.

Background: Several clinical and histological factors of primary melanomas comprise a relatively large quantity of prognostic information.

Objective: To find immunohistochemical markers that can improve the prognostic accuracy achieved by factors that are available without extra laboratory work, i.e.

Can immunohistochemical markers and mitotic rate improve prognostic precision in patients with primary melanoma?

Background: In addition to tumor thickness, several other prognostic parameters have been identified in primary human melanomas. Some are available readily (localization, gender, age, and ulceration). Others must be evaluated with a moderate or even substantial amount of work (mitoses and immunohistochemical markers).

Amelanotic malignant melanoma presenting as malignant schwannoma.

A 78-year-old woman presented with a 14-month history of a nodule on the sole of her left foot. It had been increasing in size, and had become ulcerated. Histological, immunochemical and ultrastructural studies of the primary tumour revealed melanocytic and Schwannian characteristics, and posed diagnostic difficulties.

Tumour progression and metastatic behaviour in vivo correlates with integrin expression on melanocytic tumours.

In order to evaluate the significance of adhesion molecules expressed on melanocytic tumours for progression and prognosis in vivo, we studied integrin expression (VLA-1 to VLA-6, CD18, CD51, CD61) on 10 naevi, 40 primary malignant melanomas, and 11 metastases by immunohistology using the APAAP technique. Evaluation was done by grouping the percentage of positive tumour cells in six categories. Statistical analysis (Wilcoxon rank test, Scheffe test) revealed significant differences in the expression of VLA-1 (P < 0.

Primary leiomyosarcoma of the skin. A histological and immunohistochemical analysis.

We report a rare case of a cutaneous leiomyosarcoma on the extensor surface of the proximal part of the left arm of an 84-year-old man. The tumour exhibited a number of histological and immunohistochemical features which are characteristic of a leiomyosarcoma. Leiomyosarcomas are frequently misdiagnosed on clinical grounds.

Fibroblast-Derived Factors Induce Different Mast Cell Characteristics in Human Myeloid Cell Lines and Peripheral Monocytes.

Mast cell differentiation markers were studied by culturing monocytic (U937, THP1) a promyelotic (HL60) and a human mast cell line (HMC1) and peripheral human blood monocytes with fibroblast supernatants and feeder layers. Mast cell differentiation occurred on the basis of metachromasia, chloroacetate esterase, expression of mast cell-specific antigens (APAAP) and production of tryptase in all cell types, but to varying degrees and not at all with a FcεRI marker in monocytic lines. Direct cellular contact is thus not necessary for induction of mast cell differentiation by fibroblasts.

The relationship between characteristics of the tumor cells and sex of the patients in primary malignant melanomas.

Sex is a well proven prognosticator in primary malignant melanoma. We studied 19 parameters of tumor cells in primary malignant melanoma from 391 patients, the purpose being to determine if melanomas in men and women are alike. Apart from results in thin melanomas, no difference was seen between the sex groups.

p-glycoprotein expression in malignant melanoma.

In some human malignancies resistance to chemotherapy is caused by an energy-dependent efflux system, responsible for the removal of chemotherapeutics out of the resistant tumor cells. A major component of this efflux system is the permeability glycoprotein (p-glycoprotein), which depends on the multidrug-resistance gene MDR1. We have tested p-glycoprotein in primary and metastatic human melanoma by use of the monoclonal antibody C219; a substantial expression was only observed in 1/37 primary melanomas and in 1/27 melanoma metastases.

Metastatic human melanoma. Phenotypic heterogeneity and antigen expression in relation to the clinical status.

According to animal experiments, metastasis to a particular organ depends on the phenotype of the tumor cells. Widespread metastatic dissemination including internal organs would therefore, at least in part, depend on the capacity of tumor cells to modulate, resulting in increased phenotypic heterogeneity. We found evidence for this assumption in human melanoma by phenotyping metastases (mainly cutaneous/subcutaneous) from 59 patients by the use of six monoclonal antibodies.

The Ki-67 antigen in primary human melanomas--its relationship to mitotic rate and tumor thickness and its stability.

We investigated whether two parameters of proliferative activity - mitotic rate and Ki-67 positive cells - are interchangeable. The mitotic rate was assessed on paraffin-embedded sections, Ki-67 positive cells were immunohistologically determined in frozen tissue. A poor correlation (correlation coefficient r = 0.

[Expansion behavior of intravitreous sulfur hexafluoride in exposure to nitrous oxide].

In experiments with 19 rabbits the changes in volume and concentration of intravitreously instilled sulfur hexafluoride were investigated under normal air conditions (10 rabbits in group A) and with application of laughing, gas to the inspiration system for 3 hours (9 rabbits in group B). Under normal air conditions the SF6 gas bubble attained its greatest volume after 24 hours (twice its initial volume). With the addition of 67% laughing gas to the inspiration system the largest expansion in volume (260%) was found after 3 hours, i.