Malignant melanoma is epidemic in the State of Florida and a significant public health problem. Conditional survival (CS) estimates are more meaningful for patients as they progress in their follow-up from a cancer diagnosis.
Methods: A retrospective query of a prospective database was used to abstract patients diagnosed with invasive malignant melanoma during the years 1988-2016. Patients were stratified by Stage of Disease at diagnosis. Data was generated based on 5 year disease-free survival (DFS) and overall survival (OS) from the date of diagnosis, as well as 5 year DFS and OS if patients survive 1,2,3 and 4 years without recurrence or death (Conditional Survival). All deaths in the series were from metastatic melanoma. The best prognosis group, Stage I melanoma, was compared to life tables of survival for the normal US population.
Results: There were a total of 7531 melanoma patients in the study who received their care at the University of South Florida, Lakeland Regional Cancer Center and Moffitt Cancer Center. 59% of the population was male and the mean age of the group was 57.18 years. A full 25.1% of the patients were greater than 70 years of age and 6.6% were less than the age of 30. The distribution of patients according to the Stage of disease at diagnosis was for Stage I, II, III and IV melanoma, 53.4%, 32.5%, 11.1% and 3% respectively.
For all stages of disease as patients with melanoma were followed without recurrence or death, the prognosis improved. For stage I patients 5 -year DFS calculated from diagnosis increased from 61.7% to 93.2% if patients survive up to 4 years without recurrence. Similar trends were noted for Stage II -IV disease. 5-year OS from date of diagnosis for Stage I patients also increased from 88.8% to 98.6% if patients survived 4 years. 5-year OS at any period of time during the recurrence free follow-up period was similar for patients with Stage I (88.8%, 87.2%, 86.2%, 86.4%, 86.2%) and II (66.7%, 62%, 62.8%, 64.2%, 66.1%) disease but improved significantly for Stage III (50.7%, 50.2%, 56.5%, 59.8%, 71.4%) and IV patients (27.6%, 34.9%, 48.3%, 50.0%, 68.7%) as patients survived 1,2,3 and 4 years from diagnosis. For example, if Stage III patients survive 4 years, the 5-year OS increases from 50.7% to 70.4%. The best prognostic group, those patients with Stage I melanoma who survive without recurrence for the first 4 years of follow-up continued to have an increased death rate compared to the normal population. The CS data for patients with Stage I, II and III melanoma do not substantiate any medical/legal causation arguments as long as patients do not have a recurrence in the first 4 years of follow-up.
Conclusion: Prognosis improves for melanoma patients if they survive during the follow-up period without recurrence. This was observed for all stages of disease. This data provides more meaningful recurrence and survival information for patients and their families, for clinicians, for lawyers in the medical/legal system and for the insurance industry.