Nasopharyngeal carcinoma with dermatomyositis. Analysis of 12 cases.

OBJECTIVES

To evaluate the incidence rate of nasopharyngeal carcinoma with dermatomyositis, the influence of dermatomyositis on clinical course, and complications and survival of patients with nasopharyngeal carcinoma after radiotherapy.

DESIGN

A retrospective study of 12 patients with nasopharyngeal carcinoma associated with dermatomyositis, with a maximum follow-up of 228 months.

SETTING

Academic tertiary referral center.

PATIENTS

There were 6441 new patients with nasopharyngeal carcinoma who were seen at the National Taiwan University Hospital, Taipei, during the period from 1970 through 1993. Twelve patients were found to have dermatomyositis.

MAIN OUTCOME MEASURE

Clinical manifestations of nasopharyngeal carcinoma with dermatomyositis.

RESULTS

Twenty-seven (26%) of 104 patients with dermatomyositis had an associated malignancy. Twelve of these patients were diagnosed as having nasopharyngeal carcinoma. The typical skin manifestation of dermatomyositis was found in all 12 patients. Myopathy occurred in 10 patients. Three patients died of recurrence of nasopharyngeal carcinoma, one died of a second malignancy, one died of upper gastrointestinal bleeding, and one became unavailable for follow-up. The other six patients have had disease-free survival, with a mean follow-up period of 100.5 months (range, 5 to 228 months). The 1-year survival rate was 83.8%, and the 5-year survival rate was 69.4%.

CONCLUSIONS

In Taiwan, dermatomyositis is associated with an increased incidence rate of nasopharyngeal carcinoma. A search for nasopharyngeal carcinoma in patients with dermatomyositis should be performed in areas prevalent for nasopharyngeal carcinoma. If present, nasopharyngeal carcinoma can precede, occur concurrently with, or follow the diagnosis of dermatomyositis. Treatment of nasopharyngeal carcinoma may affect myositic or cutaneous disease. The prognosis and survival rates of nasopharyngeal carcinoma remained unaffected by dermatomyositis. No complications were noted owing to the radiotherapy used to treat dermatomyositis.