Lymphocytoma cutis is a benign chronic dermatosis with a lesion of the lymphoreticular tissue. Clinically manifested by single or multiple polymorphic skin rashes, more often localized on the face. The primary element is a brown nodule the size of a pea with clear borders and a dense consistency. Slow growth and a tendency to self-resolution are characteristic. There are no subjective feelings. The diagnosis takes into account anamnesis, clinic, dermatoscopy data, serological tests, histology and immunophenotyping (the presence of polyclonal immunoglobulins). X-ray irradiation is considered a specific therapy.
Lymphocytoma cutis is a reactive benign dermatosis characterized by skin lymphoplasia, clinically and histologically resembling true lymphoma. The disease does not have a bright gender coloring, endemicity, age and racial differences. Information about the prevalence varies, which may be due to the lack of an unambiguous understanding of the term “lymphocytoma cutis”, which would suit all dermatologists.
The concept of “lymphocytoma” was introduced into dermatological practice by Kaufman in 1921, but for the first time this pathology was described in 1894 by the Austrian dermatologist Spiegler under the guise of sarcomatosis, metastases of a malignant tumor into the lymphoid system. In 1900, the German doctor Fendt managed to prove the goodness of pathological changes in this pathology. He called the disease a sarcoid, a cutaneous manifestation of sarcoidosis. It should be noted that later, in 1943, Swedish dermatologist Befverstedt united all benign lymphoreticular skin tumors into one group, which remains relevant at the present stage of dermatology development.
Lymphocytoma of the skin is considered a polyethological disease. One of the causes of this pathology, according to Ventolt (1953), Gotton (1960) and Rimbaud (1962), is a tick bite that causes the development of a reactive skin reaction at the site of the introduction of a tick toxin with a parallel spread of the pathological process through the circulatory and lymphatic system. Along with the above, there are many other theories of the origin and development of lymphocytoma. For example, in 1965, Pillsbury proposed dividing lymphocytoma cutis into single (local) and multiple (disseminated) and considering the former as benign lymphofollicular neoplasms, and the latter as a type of reticular cell lymphoma. A similar point of view was held by Piorini back in 1959, who opposed lymphocytoma cutis to malignant neoplasms of lymphoid tissue.
Since 1965, dermatology has generally accepted the point of view on lymphocytoma cutis as a kind of pseudolymph that can occur with any damage to the skin of an exo- and endogenous nature: a tick bite or another insect, injury, injection, tattooing, vaccination or acupuncture. Pathology can develop against the background of a tumor process, photodermatosis, acrosclerosis or skin diseases with the accumulation and proliferation of mast cells in tissues. In fact, a lymphocytoma cutis is a benign response of the body’s immune system and the reticular system of the skin in the form of proliferation of histiocytes, T- and B-lymphocytes to a pathological violation of the integrity of the skin.
As a protective reaction in response to any damaging onset, the mechanism of inflammation is activated, the ultimate goal of which is to destroy the pathogen and restore the integrity of the skin. Inflammation on the part of the immune system involves T-lymphocytes, which ensure the goodness of the process at the cellular level, and B-lymphocytes, which produce antibodies that are responsible for the humoral component of immunity. T- and B-lymphocytes stimulate the proliferation of atypical lymphocytes, which become one of the components of lymphocytoma cutis. The clinic, course and prognosis of the disease depend on which atypical lymphocytes predominate in the lymphocytoma cutis. On the part of the skin, macrophages are involved in inflammation, stimulating the process of hyperplasia and proliferation of dermal cells, which also become part of the pathological process. This is how an inflammatory infiltrate is formed in lymphocytoma cutis.
Since there is no consensus on the causes and development of lymphocytoma cutis, there is no generally accepted classification of this disease. Taking into account the known composition of lymphocytomas , it is customary to divide them into two groups:
- T-cell lymphocytomas of the skin, which are mainly based on T-lymphocytic infiltrate:
- Follicular lymphocytoma of the skin is a benign variant of skin lymphoma. It is characterized by damage to hair follicles under the influence of exo- and endogenous factors.
- Lymphocytoma of the skin in Lyme disease is a reactive response of the reticuloendothelial and lymphoid systems to a tick bite.
- Cesari lymphocytoma is a lymphocytic infiltration of the skin involving the bone marrow, a special type of disease, in some cases leading to chronic lymphocytic leukemia.
B-cell lymphocytomas of the skin, neoplasms with a predominance of B-cell lymphocytic infiltration:
- Benign skin lymphoplasia is the most common type of lymphocytoma, a reactive reaction of the skin and lymphoid system to pathogenic onset.
The variety of clinical manifestations of lymphocytoma cutis associated with the heterogeneity of nosological forms often entails untimely and incorrect diagnosis. A clear definition of the primary element of lymphocytoma cutis helps to reduce the number of diagnostic errors. Such an element is always a flat compacted brown knot of small size, located mainly on the skin of the face. The proportion of single neoplasms in relation to multiple ones in the clinic of lymphocytoma cutis is 2:1. Over time, the nodules change their color, which is probably due to the deposition of hemosiderin particles. There is a slow growth of elements, the tendency of nodes to self-resolution is noted. Subjective sensations in lymphocytoma cutis are absent, regional lymph nodes are not involved in the process.
Clinically, there are two variants of the course of T- or B-lymphocytoma of the skin: superficial infiltrative and tumor. The first is characterized by a rash of brown disc-shaped surface smooth infiltrates surrounded by small flaky nodular elements. A distinctive feature of the second variety are the primary elements in the form of flat semi-dense brown nodules the size of beans protruding above the surface of the dermis. The elements are localized in the deep layers of the skin and subcutaneous fat. The nodes are compressed with the skin, but they easily shift when palpating the surrounding tissues. Lymphocytoma cutis has a long course with a possible self-resolution of the process, after which, in contrast to long light intervals, a rapid relapse occurs against the background of specific therapy.
The symptoms of Cesari lymphocytoma differ from the manifestations of other types of lymphocytomas. This variety is accompanied by a constantly progressive T-helper lymphocytic infiltration of the skin against the background of itching and peeling of the epidermis. Over time, infiltration is replaced by tumor-like growths not only on the face, but also on the back and shins. Skin manifestations usually precede leukemization of the process, combined with the penetration of lymphocytes into the bloodstream. Less often, there is a simultaneous occurrence of skin manifestations and leukemia. A typical picture of the flowering of Cesari lymphocytoma includes itching, generalized erythroderma with swelling in the ankles, diffuse alopecia, nail dystrophy and infiltration of the skin of the face.
The diagnosis is carried out on the basis of anamnesis, clinical manifestations, dermatoscopy data (hemosiderin grains are visible), electron microscopy and laboratory examination (biochemistry, clinical blood tests). The final diagnosis is made after mandatory histological confirmation. Histopathology of lymphocytoma cutis is represented by intradermal large-focal lymphocytic-reticular infiltrates separated by a collagen layer from the basal layer of the epidermis. Histologically, the lymphocytoma of the skin resembles the follicles of the lymph nodes. There are several histological varieties of the disease: with infiltration from plasma cells and cells of reticular tissue, with granulomatous, lymphocytic or near-follicular infiltration.
If necessary, serological tests are carried out, identifying specific antibodies by RSC and RIGA methods, and the results of myelogram and immunophenotyping are analyzed. Lymphocytoma is differentiated with pseudolymphomas, systemic lupus erythematosus, sarcoidosis, tuberculosis of the skin, eosinophilic granuloma of the face, lymphosarcoma and leukemides of the skin.
Therapy is carried out collectively with the participation of a dermatologist, oncologist, infectious disease specialist and surgeon. A specific method of treatment is considered to be X-ray irradiation of lymphocytoma cutis followed by radical removal and a maintenance dose of postoperative radiation to prevent relapse. In some cases, cryodestruction is used. Corticosteroids are injected into the lesion. When borreliosis is established, antibiotics (ceftriaxone) are prescribed. The prognosis is favorable, constant monitoring by a dermatologist is necessary in order to exclude the transformation of a lymphocytoma cutis into a malignant neoplasm.