[Effect of interferon alfa therapy on malignant melanoma of oral mucosa]

To evaluate the effect of two adjuvant therapy in patients with resected maxillary mucosal melanoma.

Survival analysis, retrospective study. There were 165 patients with resected maxillary mucosal malignant melanoma in the study, which were divided into three group: control group (50), interferon-alpha2b group (78) and interferon-alpha2b+dacarbazine group (37). All patients had stage II or III lesions according to AJCC(2000) staying system. Cox proportional hazards model was used to analyze the statistically significant prognostic factors. Kaplan-Meire method was used to calculate the cumulated survival rate with 3 different treatments and Log-rank method for comparison of the distribution of the different survival rates in 3 groups.

The overall 3-year survival rate was 4%, with 3.0% in the control group, 4.5% in interferon-<2b group and 5.7% in interferon-alpha2b+dacarbazine group, respectively. The significant prognostic factors included thickness(P<0.001, RR=2.696), ulceration(P<0.001, RR=2.068), lymph node metastasis(P<0.001, RR=1.710) and the treatment method(P<0.001, RR=0.395). A beneficial effect in overall survival was observed in two experimental groups. But the effect appeared to become weakening after 2 years. The difference between the two experimental groups was not significant statistically.

The two conjunctive methods used in this study can improve the overall survival in patients with resected maxillary mucosal melanoma. But the beneficial effect would descend and disappear after 2 years. The effect of using interferon-alpha2b+dacarbazine was not better than that of using interferon-alpha2b alone.