Merkel cell carcinoma: A new radiation-induced cancer?

Jan 2013

[Article in French]

Bertrand M, Mirabel X, Desmedt E, Vercambre-Darras S, Martin de Lassalle E, Bouchindhomme B, Guerreschi P, Martinot V, Mortier L.

Source

Service de dermatologie, hôpital Claude-Huriez, CHRU de Lille, rue Michel-Polonovski, 59037 Lille cedex, France. Electronic address: marie_bertrand13@yahoo.fr.

Abstract

BACKGROUND:

Merkel cell carcinoma (MCC), a rare and aggressive neuroendocrine tumour, appears primarily on sun-exposed areas in light-skinned elderly subjects. UV exposure and profound immunosuppression (particularly in a setting of solid organ transplantation, haematological malignancies, HIV) constitute the principal risk factors. The aetiopathogenesis of this cancer is not known, although a polyomavirus involved in the oncogenic process was recently discovered. The carcinogenic effect of ionizing radiation, while not clearly established, has been suspected in rare cases involving the onset of MCC in irradiated zones. We report a new case of case of MCC in a patient previously undergoing radiotherapy.

CASE REPORT:

A 59-year-old-man underwent radiotherapy for a Darier-Ferrand dermatofibrosarcoma on the left shoulder and developed MCC at the same site 38 years later.

DISCUSSION:

The time between radiotherapy and diagnosis of MCC, its site within the radiation field (radio-dermatitis), the description of similar cases in the literature concerning the onset of MCC in irradiated areas, and the known carcinogenic effects of ionizing radiation all militate strongly in favour of the radiation-induced nature of MCC.

PubMed

Merkel cell polyomavirus and trichodysplasia spinulosa-associated polyomavirus DNAs and antibodies in blood among the elderly

Merkel cell polyomavirus and trichodysplasia spinulosa-associated polyomavirus DNAs and antibodies in blood among the elderly

Merkel cell polyomavirus (MCPyV) and trichodysplasia spinulosa-associated polyomavirus (TSPyV) are recently found pathogens causing two rare skin disorders, Merkel cell carcinoma (MCC) and trichodysplasia spinulosa (TS). MCC is proportionally common in the elderly and most often is associated with immunosuppression.

TS is a folliculocentric infection seen in patients in an immunocompromised state. Little or no baseline information exists, however, on the prevalences of these two viruses among the elderly.

Epidemiologic data on this population could help in understanding their natural biology. We wished to determine the occurrences and blood levels of MCPyV and TSPyV DNAs among the elderly and any association between the prevalences of their corresponding antiviral IgG antibodies. 

Methods: From 394 hospitalized elderly individuals (age >=65 years) with respiratory symptoms, cardiovascular, and other diseases, we studied 621 serum samples by four different real-time quantitative (q) PCRs, two for the DNAs of MCPyV and two for TSPyV.

The IgG antibodies for both viruses among 481 serum samples of 326 subjects were measured with enzyme immunoassays (EIAs), using as antigen recombinant virus-like particles (VLPs). 

Results: Of the 394 patients, 39 (9.9%) were positive at least once for MCPyV DNA by the LT PCR, and 33 (8.4%) by the VP1 PCR, while 6 (1.5%) were positive by both PCR assays. In general, the viral DNA copy numbers were low.

In sharp contrast, no TSPyV DNA was detectable with qPCRs for the corresponding genomic regions. The IgG seroprevalence of MCPyV was 59.6% and of TSPyV, 67.3%. 

Conclusions: MCPyV DNA, unlike TSPyV DNA, occurs in low copy number in serum samples from a notable proportion of aging individuals.

Whether this reflects enhanced viral replication possibly due to waning immune surveillance, and is associated with increased MCC risk, deserves exploration.

Author: Mohammadreza SadeghiMatti AronenTingting ChenLaura JarttiTuomas JarttiOlli RuuskanenMaria Söderlund-VenermoKlaus Hedman
Credits/Source: BMC Infectious Diseases 2012, 12:383

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