The role of cytological examination in the early diagnosis of non-pigmented skin melanoma: two clinical cases

Background. Cutaneous melanoma, originating from epidermal melanocytes, is one of the most aggressive tumors that metastasizes both via lymphatic and hematogenous routes. The tumor is brown or black in color, as melanoma cells continue to synthesize the pigment melanin. However, in some cases, the pigment is not detected in the tumor or is present in small amounts, and the melanoma becomes amelanotic, resembling a hemangioma or papilloma. Economical removal of such a formation is fraught with recurrence and a worsening prognosis. In these cases, cytological examination of a scraping or fine-needle aspirate of the formation can establish the correct diagnosis. However, many oncologists are hesitant to use this method, as they believe that trauma can accelerate tumor growth. At the P. A. Herzen Moscow Research Oncology Institute, cytological examination of melanoma scraping or aspirate has been used since the early 1970s. Practice has shown that minor trauma does not affect the disease prognosis. In 1974, methodological guidelines titled "The Use of the Cytological Method in the Diagnosis of Skin Melanomas" were published. The aforementioned method is also used at the N. N. Petrov National Medical Research Center of Oncology, but no impact on prognosis has been observed. Currently, it is established that two factors influence melanoma prognosis: tumor thickness and the level of dermal invasion. Other factors are insignificant. Fiveyear survival rates are 95% for tumors less than 1 mm thick and 45% for tumors 4 mm or thicker.

Conclusion. Two clinical cases are presented where cytological examination of small amelanotic lesions allowed for the early detection of melanoma. In the first case, the melanoma thickness was 0.7 mm and the invasion level was 3. In the second case, the thickness was 0.68 mm and the invasion level was 2. In the first case, the patient was examined 4 years and 11 months after treatment, and in the second case, 10 months after treatment, with no signs of recurrence detected. The conclusion is drawn about the necessity of applying the cytological diagnostic method in the daily practice of surgeons, dermatologists, and oncologists for the early detection of amelanotic melanoma of the skin.

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