Melanoma of anorektalny area
Melanoma of anorektalny area – the malignant new growth which is developing from melanotsit and localized in nizhneampulyarny department of a rectum or in various areas of an anorektalny zone. It is shown by bleedings, pains, feeling of a foreign matter in the field of back pass, locks, tenezma and an anal itch. It is inclined to early limfogenny and hematogenic metastasis, malfunction of various bodies because of defeat by metastasises can become the first clinical symptom of a tumor. The diagnosis is established on the basis of complaints, the anamnesis, data of the general and rectal survey, studying of dabs prints and other researches. Treatment is quick.
Melanoma of anorektalny area
Melanoma of anorektalny area – the malignant melanotsitarny tumor located in the lower departments of a rectum or area of an anus. Makes 2-3% of total of melanomas and 0,25-1,8% of total of malignant new growths of a rectum. Average age of patients – comes to light 45 years in different age groups. Equally often strikes men and women. As well as other malignant tumors coming from melanotsit differs in bystry progressing and metastasis.
Because of external similarity to other diseases, frequent lack of a pigment or insufficient pigmentation the melanoma of anorektalny area can incorrectly be diagnosed that worsens the forecast even more. Frequency of diagnostic mistakes at primary address reaches 35%. Patients can receive treatment concerning polyps of a rectum, hemorrhoids, an anal crack, a paraproktit, cancer of a rectum and other diseases. In some cases clinical manifestations are absent, the tumor is found when carrying out inspection in other occasion. Treatment is performed by experts in the field of oncology and a proktologiya.
The melanoma can arise in ampulyarny department of a rectum, area of the anal channel or (more rare) than an ampulyarny ring. Usually grows ekzofitno, on appearance reminds gemorroidalny knot or a polyp on a narrow leg or the wide basis. Endofitny growth with formation of izjyazvlenny infiltrates is less often observed. Sometimes the saucer-shaped melanomas of anorektalny area externally similar to carcinomas surrounded with accurately expressed roller meet. The size of a new growth can fluctuate from 1 to 8 cm. In 20% of cases multiple tumors come to light. Color of a melanoma can be black, dark brown, cherry or claret. "Motley" new growths meet the zones alternating pigmented and not pigmented. In 50% of cases of a melanoma of anorektalny area are deprived of pigmentation.
Taking into account features of a histologic structure distinguish four types of tumors: epiteliopodobny, veretenokletochny, kruglokletochny and polimorfnokletochny. At a research of epiteliopodobny melanomas of anorektalny area solid nests around which argirofilny membranes settle down come to light. When studying veretenokletochny new growths individual opleteniye of cages are found. Single round cages of the small size are characteristic of kruglokletochny tumors, argirofilny fibers are absent. "Pure" new growths meet seldom, in the majority of a melanoma of anorektalny area consist of sites of fabric with various structure.
Symptoms of a melanoma of anorektalny area
In most cases (more than 80%) blood impurity in Calais becomes the first symptom of a tumor. Because of a low arrangement of a melanoma hemoglobin does not manage to turn into muriatic hematin therefore blood remains the kalovy masses, bright red, well noticeable on a surface. More than a half of patients complain of pains in the field of an anus. Among less widespread displays of a melanoma of anorektalny area – feeling of a foreign matter, tenezma, feeling of incomplete depletion of intestines, locks and an itch in the field of back pass. Some patients report about existence of opukholevidny education in the field of an anus. Sometimes the melanoma drops out of a rectum during defecation, and patients set it a hand.
In a zone of a rectum a large number of blood and lymphatic vessels settles down, it causes tendency of a melanoma of anorektalny area to early metastasis. At the time of primary address metastasises come to light almost at 20% of patients, in the subsequent arise more than at a half of patients. The melanoma of anorektalny area usually spreads in inguinal lymph nodes, bones, lungs, a liver and skin. Sometimes metastasises or the related dysfunction of internals become the first clinical display of a disease. The expressed infiltrative growth with defeat of the next bodies is observed less often. The melanoma can sprout big vulvar lips, a vagina, a root of a scrotum, a basin wall etc.
Diagnostics and treatment of a melanoma of anorektalny area
The diagnosis is established taking into account complaints, the anamnesis, results of the general survey, rectal survey and a research of dabs prints. Rectal survey is carried out very carefully, without using a mirror. Carrying out a biopsy at suspicion of a melanoma of anorektalny area is contraindicated. In doubtful cases the express biopsy is shown during surgical removal of a malignant new growth. For identification of metastasises of patients direct to a thorax X-ray analysis, a X-ray analysis and a stsintigrafiya of bones, ultrasonography of a liver and other researches.
The melanoma of anorektalny area is differentiated with trombirovanny gemorroidalny knot, a good-quality and malignizirovanny adenomatozny polyp, cancer of a rectum, limfosarkomy, kartsinoidy and malignant shvannomy. Due to the lack of specific symptomatology, external similarity of a melanoma of anorektalny area to other new growths and frequent lack of pigmentation differential diagnostics on the basis of clinical signs causes essential difficulties. The main method is the microscopy of dabs prints. Use the special methods of coloring of samples allowing to reveal pro-melanin. Pay attention to existence of signs of oppositional growth at the edges of a new growth.
The main method of treatment of a melanoma of anorektalny area is surgical intervention. Whenever possible carry out a bryushnoanalny extirpation of a rectum. At metastasis in inguinal lymph nodes carry out their removal. Palliative operations are inefficient and even in combination with other techniques (chemotherapy, radiotheraphy) have no significant effect on life expectancy of patients.
Because of an asymptomatic or malosimptomny current, the late address to the oncologist and difficulties of diagnostics treatment of melanomas of anorektalny area, as a rule, begins when the tumor already reached the considerable sizes and got deeply into the subject fabrics. The melanomas of any localization revealed at this stage differ in extremely adverse current. According to the Russian oncologists, now average five-year survival at a melanoma of anorektalny area fluctuates within 12 - 22%.