Estimating the cure proportion of malignant melanoma, an alternative approach to assess long term survival: a population-based study.
OBJECTIVE
A large proportion of patients with cutaneous malignant melanoma (CMM) do not experience excess mortality due to their disease. This group of patients is referred to as the cure proportion. Few studies have examined the possibility of cure for CMM. The aim of this study was to estimate the cure proportion of patients with CMM in a Swedish population.


METHODS
We undertook a population-based study of 5850 CMM patients in two Swedish health care regions during 1996-2005. We used flexible parametric cure models to estimate cure proportions and median survival times (MSTs) of uncured by stage, sex, age and anatomical site.


RESULTS
Disease stage at diagnosis was the most important factor for the probability of cure, with a cure proportion of approximately 1.0 for stage IA. While the probability of cure decreased with older age, the influence of age was smaller on the MST of uncured. Differences in prognosis between males and females were mainly attributed to differences in cure as opposed to differences in MST of uncured.


CONCLUSIONS
This population-based study showed approximately 100% cure among stage IA disease. Almost 50% of patients had stage IA disease and the high cure proportion for this large patient group is reassuring.
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. Electronic address: therese.m-l.andersson@ki.se.
Therese M-L
TM
Andersson
Department of Medicine, Unit of Dermatology, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden; Department of Oncology-Pathology, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden.
Hanna
H
Eriksson
Department of Oncology-Pathology, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden.
Johan
J
Hansson
Department of Oncology-Pathology, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden.
Eva
E
Månsson-Brahme
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Paul W
PW
Dickman
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Sandra
S
Eloranta
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; Regional Cancer Centre, Uppsala University Hospital, Uppsala, Sweden.
Mats
M
Lambe
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; University of Leicester, Department of Health Sciences, Leicester, UK.
Paul C
PC
Lambert
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008545:Melanoma / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology*; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012042:Registries; D012737:Sex Factors; D012878:Skin Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology*; D016019:Survival Analysis; D013548:Sweden / Q000453:epidemiology; D016896:Treatment Outcome; D055815:Young Adult
Cure; Flexible parametric model; Malignant melanoma; Population-based; Relative survival; Survival