Malignant choroidal melanoma

Malignant choroidal melanoma is the most common primary intraocular malignancy in adults. Controversy has surrounded the treatment and management of these tumors for many years. The Collaborative Ocular Melanoma Study (COMS) is a randomized, controlled, clinical trial funded by the NEI. The study was established to answer the question: what type of treatment is most likely to cause tumor regression, and provide the patient with the best prognosis for cancer free survival? Patients with small tumors were followed annually for 2 years and again 5 years later to determine growth rates for these tumors. Patients with medium, and large tumors are randomized to various treatment strategies. These patients are followed bi-annually with a complete ophthalmic examination and once a year with a complete medical/oncological evaluation. The small tumor arm has completed enrollment with 188 patients. Thirty-one percent of these patients had significant growth of their tumor and were subsequently treated. Final conclusions from the medium tumor arm and the large tumor arm of the trial are pending. A case presentation of a patient with a medium size tumor and an update on the study design and the COMS data gathered to date will be discussed.     

Malignant melanoma of the cervix. Report of a case

A malignant melanoma of the cervix, a rare neoplasm, was found to have an unusual cytologic pattern, similar to that of a leiomyosarcoma. A biopsy sample was diagnosed as cervical malignant melanoma of the spindle cell type. Some neoplastic cells in the tissue contained melanin pigment, whereas none of the abnormal cells in the cervical scrapes, except for an abnormal giant cell, had visible cytoplasmic pigment. The abnormal cells in the cervical scrape specimen were spindle-shaped, as were their nuclei, which is why the cytologic pattern was interpreted as that of a leiomyosarcoma. Evidence from this and previously reported cases shows that malignant melanoma must be considered as a possible source of exfoliated abnormal nonpigmented spindle-shaped cells in a cervicovaginal cell sample.     

Malignant melanoma and melanocortin 1 receptor

The conventional chemotherapeutic treatment of malignant melanoma still remains poorly efficient in most cases. Thus the use of specific features of these tumors for development of new therapeutic modalities is highly needed. Melanocortin 1 receptor (MC1R) overexpression on the cell surface of the vast majority of human melanomas, making MC1R a valuable marker of these tumors, is one of these features. Naturally, MC1R plays a key role in skin protection against damaging ultraviolet radiation by regulating eumelanin production. MC1R activation is involved in regulation of melanocyte cell division. This article reviews the peculiarities of regulation and expression of MC1R, melanocytes, and melanoma cells, along with the possible connection of MC1R with signaling pathways regulating proliferation of tumor cells. MC1R is a cell surface endocytic receptor, thus considered perspective for diagnostics and targeted drug delivery. A number of new therapeutic approaches that utilize MC1R, including endoradiotherapy with Auger electron and α- and β-particle emitters, photodynamic therapy, and gene therapy are now being developed.     

Malignant melanoma of the palpebral conjunctiva in a captive fallow deer.

A case of malignant melanoma in the conjunctiva of the eyelid of a captive 13-yr-old female fallow deer (Dama dama) was studied. The black tumor that protruded to the palpebral conjunctiva of the right lower eyelid consisted of an infiltrative growth of melanin-containing neoplastic cells with marked cytological atypia. The tumor involved the conjunctiva of the right lower eyelid and infiltrated to the conjunctival epithelial layer, but did not reach the palpebral skin. Numerous mitotic figures and lymphatic invasions were observed. This is a very rare case of a malignant melanoma arising from the palpebral conjunctiva in a wild ruminant.     

Malignant melanoma metastatic to the endometrium. Cytologic findings in a direct endometrial sample

A 38-year-old woman was hospitalized with uterine bleeding and a history of malignant melanoma. Endometrial biopsy had already documented the presence of rare uterine metastases from a cutaneous lesion surgically removed from the back 1.5 years previously. While a cervicovaginal smear was negative, smears of a sample obtained from the uterine cavity by the Mi-Mark endometrial helix showed the cytomorphologic features of melanoma, corresponding to those seen in the primary lesion. The finely granular cytoplasmic pigment seen in the smears was proven to be melanin by the use of potassium permanganate oxidation. The patient then underwent hysterectomy. This case demonstrates the potential utility of direct endometrial sampling in diagnosing difficult cases.     

Malignant melanoma in fine needle aspirates and effusions. An immunocytochemical study using monoclonal antibodies

The value of monoclonal antibodies (MAbs) for the immunodetection of keratin, vimentin and two melanoma-associated antigens recognized by NKI/C3 and NKI/Bteb for the diagnosis of malignant melanoma has been previously established on histologic preparations. In the present study, cytologic preparations from 20 fine needle aspirates and effusions from patients with malignant melanoma were evaluated using these antibodies. Twenty of 20 smears were negative for keratin, and 20 of 20 smears were positive for vimentin. Positivity for NKI/C3 was seen in 12 of 12 cases studied, and for NKI/Bteb in 12 of 13 cases. These results indicate that a panel of MAbs consisting of anti-keratin, anti-vimentin, NKI/C3 and NKI/Bteb is useful for a more accurate diagnosis of malignant melanomas on cytologic preparations. The expression of these antigens in melanoma cells in cytologic smears can be a valuable aid in the detection of primary (noncutaneous) and metastatic melanomas by fine needle aspiration.     

Malignant melanoma metastatic to the liver. A cytomorphologic comparative study to identify reproducible diagnostic criteria

OBJECTIVE: To establish cytomorphologic criteria that might facilitate the identification of malignant melanoma (MM) cells with epithelioid (nevoid) morphology, in fine needle aspiration biopsy material from the liver. STUDY DESIGN: Aspirated material from 18 cases of MM with epithelioid features and 24 cases of benign liver lesions (BLL) were examined. The cases were selected based on the availability of corresponding tissue biopsies, adequate cell block material or sufficient number of direct smears to perform immunocytochemical staining. The presence or absence of 7 cytologic criteria were reviewed, and the results were evaluated by multivariate regression analysis. RESULTS: All evaluated criteria were significant for identifying MM cells and differentiating them from reactive hepatocytes (P < .001). Uniform atypia, cell dyscohesion, eccentric nuclei and irregular nuclear membranes supported MM, whereas, monolayered sheets or cordlike arrangement; coarse, granular cytoplasm; and occasional transgressing endothelium in true tissue fragments were evidence of BLL. CONCLUSION: A systematic evaluation of the cytomorphologic features described in this study, in conjunction with the clinical and radiologic findings, can be used to render an immediate, confident and accurate diagnosis of MM metastatic to the liver.     

Malignant melanoma in a captive red deer (Cervus elaphus elaphus)

We report a case of malignant melanoma in a captive red deer (Cervus elaphus elaphus). The primary lesion was on the plantar aspect of the right pastern and infiltrated the surrounding skin, but not underlying tendons or bone. Diffuse metastasis to the regional lymph nodes had occurred. Histologically, lesions were characterized by large numbers of variably pigmented epithelioid cells with a high degree of nuclear atypia and many mitotic figures. This is the first reported case of this neoplasm in red deer.