Environmental Risk Factors for Mycosis Fungoides

Abstract

The rising incidence rates of mycosis fungoides (MF) call for an explanation. Thus, environmental and lifestyle factors were speculated to play a role in the development of lymphoproliferative diseases. It is thought that continuous activation of skin T helper lymphocytes leads to malignant transformation of a specific clone. Possible risk factors that have been implicated are occupational chemical exposure, radiation, drugs and infections. The carcinogenic process is probably multifactorial and multistep, combining the genetic predisposition of the individual and his immune status with various exogenous factors. Using advanced and accurate exposure assessment tools, recent epidemiological data indicate that occupational exposure to chemicals, primarily to aromatic halogenated hydrocarbons, is a major risk factor to develop MF in men (odds ratio 4.6), while exposure to pesticides, a subgroup of the aromatic halogenated hydrocarbons, is a risk factor in both genders (odds ratio 6.8 for men and 2.4 for women). Apparently, concomitant infection with Staphylococcus aureus or with Borrelia species and chronic exposure to UVR are minor risk factors for the development of MF. Further assessment of occupational and environmental exposures is essential for the evaluation of their contribution to the etiology of MF. This will allow the application of preventive and surveillance measures along with adjustment of existing health policies.

Cutaneous T‐cell lymphoma: 2011 update on diagnosis, risk‐stratification, and management

“…Epidemiological studies have failed to consistently identify environmental or virally-associated risk factors for most CTCL subtypes, with the notable exception of human T-cell lymphotropic virus-1 (HTLV-1) infection in adult T-cell leukemia/lymphoma [8][9][10][11]. Rare reports of familial MF and the detection of specific HLA class II alleles in association with both sporadic and familial MF suggest that host genetic factors may contribute to MF development [12][13][14].…”

Whole-genome sequencing reveals oncogenic mutations in mycosis fungoides

“…1 Mycosis fungoides (MF), the most common form of CTCL, classically presents as patches and plaques on the skin with disease progression leading to skin tumors, and lymph node, blood, and visceral involvement. The etiology of MF is unknown, but is thought to include chronic antigenic stimulation through viral/bacterial exposure, 2,3 environmental exposures, 4 and altered microRNA (miRNA) expression. 5,6 A variety of genetic aberrations have been identified in MF.…”

Identification of geographic clustering and regions spared by cutaneous T‐cell lymphoma in Texas using 2 distinct cancer registries

“…16 These and similar findings triggered an extensive search for a viral, chemical, or occupational disease trigger, but failed to yield any conclusive etiologic agent. [17][18][19] Some patients with smoldering human T-cell lymphotropic virus 1-associated adult T-cell lymphoma present with MF skin lesions, 20,21 but based on other studies, viruses have not been identified in the vast majority of MF cases. 22,23 In the current study, we analyzed the demographic data regarding CTCL in Houston specifically and other areas of Texas using 2 distinct databases, The University of Texas MD Anderson Cancer Center (MDACC) CTCL clinic patient database and the statewide population-based Texas Cancer Registry (TCR), to demonstrate the existence of disease clustering in several communities in Texas.…”