Dermatomyositis associated with malignant melanoma--a marker of poor prognosis?

Dermatomyositis (DM) is an inflammatory connective tissue disorder well recognized as a paraneoplastic syndrome in adults.

The objective of this study was to assess the prognosis of DM associated with malignant melanoma (MM).

We systematically searched databases (PubMed, MEDLINE, and WEB OF SCIENCE) for articles reporting the concurrence of DM and MM. For the literature study, time of onset of DM in relation to diagnosis of MM (before, concomitant with, or after), stage of MM after restaging (according to the American Joint Committee on Cancer [AJCC] guidelines, 2001), and survival time after diagnosis of DM were recorded. Survival time studies and univariate statistical analyses were performed. Furthermore, we present our own clinical case of a patient with DM concomitantly occurring with regional lymph node metastasis of MM.

In 5 cases DM occurred before, in 6 cases concomitantly with, and in 6 cases after progression of MM. Univariate analysis identified the AJCC stage of MM as a significant prognostic factor. Gender, age, and the time interval between onset of DM and progression of melanoma were unrelated. The 1-year actuarial survival rate was 0% for patients with DM when occurring with MM at stage IV and 60% when occurring with MM at stage III (P < .05). The estimated mean survival time was 6.6 months for patients with MM stage IV and 57 months for stage III.

The conclusions from this study are limited by the relatively small number of articles that reported the association of MM and DM.

DM occurring in patients with MM at stage IV is connected with an extremely poor prognosis, whereas the few reported patients with DM and MM at stage III, including our case, have a prognosis similar to stage III patients without DM.