Earlier diagnosis of second primary melanoma confirms the benefits of patient education and routine postoperative follow-up.

Abstract

Rising health care costs have caused providers to question the benefit of regular follow-up after treatment for patients with early stage cutaneous melanoma. The authors hypothesized that routine reassessment and careful education of these patients would facilitate earlier diagnosis of a subsequent second primary melanoma, as reflected by reduced thickness of that lesion. A prospective melanoma data base was used to identify patients who developed a second primary melanoma after treatment for American Joint Committee on Cancer (AJCC) Stage I or II cutaneous melanoma. After excision of the initial primary melanoma, all patients underwent routine biannual follow-up for new primary lesions. Follow-up consisted of a questionnaire and a complete skin examination by a physician. In addition, patients were regularly educated regarding the increased risk of developing a second melanoma. A paired t test was used to examine AJCC stage, thickness, and level of invasion of the initial melanoma compared with the second primary melanoma. Of 3310 patients with AJCC Stage I or II melanoma, 114 patients (3.4%) developed a second primary melanoma. AJCC staging of both first and second melanomas was available in 82 patients (72%). When the AJCC stages of first and second melanomas were compared, 39 of 82 patients (48%) had lower stage second primary lesions, and 41 (50%) had same-stage second primary lesions. The mean tumor thickness was 1.32 +/- 1.02 mm for the initial melanoma, decreasing to 0.63 +/- 0.52 mm for the second melanoma; in fact, tumor thickness increased in only 4 of 51 patients (8%) whose records contained data for both first and second melanomas. Similarly, the level of invasion decreased in 60% of patients, remained the same in 27% of patients, and increased in only 13% of patients. By paired t test, the differences in AJCC stage, tumor thickness, and level of invasion between first and second melanomas were each highly significant (P = 0.0001). In this study, the second primary melanoma in patients with a prior cutaneous melanoma was significantly thinner than the initial primary lesion. This is evidence that careful follow-up and patient education allow earlier diagnosis. All patients diagnosed with cutaneous melanoma should be counseled regarding the risks of second melanoma and should undergo lifelong follow-up at biannual intervals.