Mycosis fungoides is a malignant tumor lesion of the lymphoid-reticular system, primarily of the skin, and later of the internal organs. Mycosis fungoides is a T-cell lymphoma. In the classic version, the disease goes through erythematous, plaque and tumor stages. Diagnosis of the disease in the first stage is difficult due to the similarity of the clinical picture with psoriasis, eczema and other dermatoses. The histological picture at this stage has no specific signs and only a thorough immunohistochemical examination helps in the timely diagnosis of the disease. It is of great importance, since treatment initiated at the erythematous stage allows prolonging the life of patients with mycosis fungoides.
C84.0 Mycosis fungoides
Mycosis fungoides is a fairly rare type of T-cell lymphoma of the skin, the disease is observed in 1 case per 345,000 population. In most cases (70-80%), people from 40 to 60 years old get sick. In men, the disease is somewhat more common than in women. Mycosis fungoides is based on the reproduction and malignant degeneration of T-lymphocytes. The exact reasons triggering this mechanism have not yet been determined. It is assumed that genetic factors and chronic antigenic stimulation play a certain role in persistent viral infection (herpes infection, HPV, etc.).
The classical form of Alibera-Bazin’s mycosis fungoides is characterized by 3 stages of the disease development: erythematous, plaque and tumor. In the erythematous stage, strongly itchy spots of red-cyanotic, red or yellowish-pink color appear on the skin. They range from a few millimeters in diameter to 15-20 cm. The spots have a flaky or wet surface. The location of elements on the trunk and extensor surfaces of the arms and legs is often noted, however, eruptions of mycosis fungoides can be of any localization. Itching sometimes precedes the appearance of spots. In most cases, it is a characteristic feature of mycosis fungoides, but it may also be absent.
The picture of rashes is identical to the picture of parapsoriasis, During’s herpetiform dermatitis, eczema or lichen planus. Therefore, some authors believe that the erythematous stage is one or another dermatosis, which then transforms into a mycosis fungoides.
The transition of the erythematous stage of classical form to plaque occurs after a different period of time: from several months to a dozen years. In the plaque stage, the spots of mycosis fungoides infiltrate, become dense and rise above the surface of the skin, transforming into plaques. The area of the plaque begins to grow, the color becomes purple or brick-red, the surface becomes fine-browned. Characterized by increased itching. Over time, plaques can undergo reverse development, which begins in their center. At the same time, the plaque continues to grow along the periphery, forming a ring. Plaques merging with each other with regression in the center form bizarre figures in the form of arcs and garlands on the skin.
In the tumor stage of mycosis fungoides, skin elements turn into tumor lesions that can reach the size of an orange and have a reddish-blue or reddish-yellow color. Along with such tumor formations on the skin, elements of the plaque stage are also observed. After a few weeks, the tumors disintegrate with the formation of deep ulcers covered with purulent-bloody discharge and masses of necrotic tissues. The patient has malaise, lack of appetite, weight loss. The tumor stage proceeds with the defeat of internal organs, in which formations similar to skin appear.
All stages of mycosis fungoides occur with an increase in lymph nodes, primarily inguinal and femoral. Body temperature rises and night sweats are possible. Almost 70% of patients with mycosis fungoides have trophic disorders: dystrophic changes in nails and hair, skin hyperpigmentation, sweating disorders, etc. Mucosal lesions are quite rare. Elements in such cases usually appear on the hard and soft palate. They quickly transform into extensive ulcers.
The Vidal-Broca form (decapitated mycosis fungoides) refers to reticulosarcomatosis of the skin. It is characterized by the absence of erythematous and plaque stages and the appearance of tumor formations on the skin of the trunk, face and limbs at once.
The erythrodermic form of Gallopo-Benier is characterized by the prevalence of redness throughout the skin, swelling, pronounced infiltration and peeling of the skin. The disease is accompanied by a high temperature reaction, a violation of general well-being.
At the beginning of mycosis fungoides in the blood, as a rule, there is an increase in leukocytes, lymphocytes and eosinophils. In the tumor stage and in the erythrodermic form, there is a decrease in the number of leukocytes and lymphocytes, an increase in ESR. To confirm the mycosis fungoides, an immunohistochemical study is performed.
The study of the skin elements of mycosis fungoides is preliminarily carried out by dermatoscopy and ultrasound of the skin neoplasm. Histological examination of the skin area taken from the pathological focus by biopsy, in the first stage of mycosis fungoides, reveals edema and acanthosis in the spiny layer of the epidermis (loss of connections between cells), accumulation of lymphocytes, fibroblasts, mast cells and eosinophils. In the plaque stage, acanthosis is pronounced sharply, nest-like clusters of histiocytes and lymphocytes are detected. In the tumor stage, the infiltrate spreads not only to all layers of the dermis, but also to the subcutaneous tissue, sometimes capturing the underlying tissues.
In the tumor stage, abdominal ultrasound and chest x-ray are performed to detect lesions of internal organs. Differentiate mycosis fungoides with Cesari syndrome and other lymphomas, systemic vasculitis, chronic dermatitis, psoriasis, etc.
In the treatment of mycosis fungoides, corticosteroids (dexamethasone, prednisone, etc.), antitumor antibiotics and cytostatics (methotrexate, sulfadiazine, cyclophosphamide, prospidine, dipin) are used. Combination therapy with drugs of these groups is more often used. It is possible to conduct phototherapy, radiotherapy, extracorporeal photochemotherapy. Locally, corticosteroid ointments are used to reduce itching.
The prognosis is unfavorable. Depending on the form and severity, the disease can last from 2 to 12 years. In many cases, timely diagnosis and initiation of treatment in the first two stages of mycosis fungoides can achieve long-term remission and prolong the life of patients.