Survival rates for lentigo maligna (LM) melanoma-type melanomas vary. Acral lentiginous melanoma has a significantly worse survival rate than other melanoma subtypes with race appearing to play a role. Another factor may be poor awareness.
Survival rates for lentigo maligna (LM) melanoma-type melanomas vary with the melanoma’s thickness.
“It is thought to have a higher recurrence rate than other subtypes,” Jennifer Stein, M.D., Ph.D., associate professor, New York University School of Medicine, New York, NY, says.
A study1 found that following the management of LM with staged excision with an average follow-up of 57 months showed that 95% of patients had no recurrence. Three patients had local recurrence and no patients had evidence of metastasis. The cure rate is greater than that reported for standard excision and is similar to that for other margin-control techniques, says Clara Curiel-Lewandrowski, M.D., associate professor of medicine and dermatology, and clinical director, Cutaneous Oncology Program, Skin Cancer Institute, University of Arizona, Tucson, Ariz. The overall survival rate for melanoma in situ (MIS) LM type is 100%.
Acral lentiginous melanoma (ALM), in comparison, has a significantly worse survival rate than other melanoma subtypes. In the case of ALM, a difference in survival according to race has been reported. One study2 showed the proportion of ALM among all melanoma subtypes was greatest in blacks (36%).
ALM had 5- and 10-year melanoma-specific survival rates of 80.3% and 67.5%, respectively, which were less than those for all cutaneous malignant melanomas overall (91.3% and 87.5%, respectively). It’s uncertain why ALM has a worse prognosis than other melanoma subtypes.2
The ALM 5- and 10-year melanoma-specific survival rates were highest in non-Hispanic whites (82.6% and 69.4%), intermediate in blacks (77.2% and 71.5%) and lowest in Hispanic whites (72.8% and 57.3%) and Asian/Pacific Islanders (70.2% and 54.1%).2 Factors such as increased tumor thickness and more advanced stage at presentation are the most likely explanations, Dr. Curiel-Lewandrowski says.
Another study3 performed at New York University showed that 49% of ALMs recurred, compared to 30% in a similarly matched population of non-ALMs.
ALM recurs more frequently than other subtypes of melanoma. In this instance, this may be related to the difficulty in margin control with ALM, Dr. Stein says.
It’s uncertain why ALM has a worse prognosis than other melanoma subtypes. “One possibility is that it is detected later because of poor awareness about ALM,” Dr. Stein concludes.
1 Bub JL, Berg D, Slee A, Odland PB. Management of lentigo maligna and lentigo maligna melanoma with staged excision. Arch Dermatol. 2004;140:552-558.
2 Bradford PT, Goldstein AM, McMaster ML, Tucker MA. Acral lentiginous melanoma: incidence and survival patterns in the United States, 1986-2005. Arch Dermatol. 2009 Apr;145(4):427-434. doi: 10.1001/archdermatol.2008.609.
3 Gumaste PV, Fleming NH, Silva I, et al. Analysis of recurrence patterns in acral versus nonacral melanoma: should histologic subtype influence treatment guidelines? J Natl Compr Canc Netw. 2014 Dec;12(12):1706-1712.