Vitamin D deficiency is associated with greater tumor size and poorer outcome in Merkel cell carcinoma patients.
BACKGROUND
Merkel cell polyomavirus has been recognized to be associated with Merkel cell carcinoma (MCC), but the evolution of this cancer probably depends on various factors. Vitamin D deficiency, defined by serum 25-hydroxyvitamin D levels <50 nmol/L, seems to influence cancer behavior and progression, but has never been assessed in MCC patients.


OBJECTIVE
First, to evaluate whether vitamin D deficiency was associated with tumor characteristics and prognosis in a cohort of MCC patients. Second, to assess expression of the vitamin D receptor (VDR) in MCC tumors.


METHODS
Clinical findings, Merkel cell polyomavirus markers and vitamin D status were assessed in a cohort of French MCC patients. The study was limited to the 89 patients for whom the serum sample had been collected within 3 years after the diagnosis of MCC. Correlation between vitamin D deficiency and MCC characteristics and outcome were determined in regression analyses. VDR expression in MCC tumours was assessed by immunohistochemistry.


RESULTS
Vitamin D deficiency was noted in 65.1% of the patients and was independently associated with greater tumor size at diagnosis (P = 0.006) and with metastasis recurrence (HR, 2.89; 95% CI, 1.03 to 8.13; P = 0.043), but not with death from MCC, although there was a trend (HR, 5.28; 95% CI, 0.75 to 36.96; P = 0.093). VDR was found to be strongly expressed in all 28 MCC tumor specimens investigated.


CONCLUSIONS
The association between vitamin D deficiency and MCC characteristics and outcome, together with detection of the VDR in MCC cells, suggest that vitamin D could influence the biology of MCC.
INRA ISP, UMR 1282, Tours, France; Université François Rabelais, Tours, France; CHRU de Tours, Service de Dermatologie, Tours, France.
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Samimi
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Touzé
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Laude
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Le Bidre
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F
Arnold
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Carpentier
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C
Gardair
A
A
Carlotti
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E
Maubec
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N
Dupin
F
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Aubin
M F
MF
Avril
F
F
Rozenberg
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Avenel-Audran
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Guyetant
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Lorette
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Machet
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Coursaget
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015266:Carcinoma, Merkel Cell / Q000150:complications* / Q000473:pathology / Q000628:therapy; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018167:Receptors, Calcitriol / Q000378:metabolism; D012878:Skin Neoplasms / Q000150:complications* / Q000473:pathology / Q000628:therapy; D016896:Treatment Outcome; D014807:Vitamin D / Q000097:blood; D014808:Vitamin D Deficiency / Q000150:complications* / Q000378:metabolism / Q000473:pathology
D018167:Receptors, Calcitriol; D014807:Vitamin D