Incidence of lentigo maligna in Olmsted County, Minnesota, 1970 to 2007

Abstract

Background The incidence of lentigo maligna (LM) may be increasing, but no population-based epidemiologic studies have been performed. Objective To determine the incidence of LM in Olmsted County, Minnesota, as well as overall and recurrence-free survival. Methods Using the Rochester Epidemiology Project, we identified all adult residents of Olmsted County, Minnesota, with a first lifetime diagnosis of LM between 1970 and 2007. Medical records were reviewed to determine demographic, clinical, and surgical data, and incidence and survival were calculated. Results Among 145 patients identified, median (range) age at diagnosis of LM was 70 (33-97) years. Treatment changed over time, with Mohs micrographic surgery becoming available after 1986. No patients died of LM; 5 had local recurrence. Estimated local recurrence-free survival at 5, 10, 15, and 20 years after diagnosis was 98%, 96%, 92%, and 92%, respectively. Overall age- and sex-adjusted incidence of LM among adults was 6.3 per 100,000 person-years, increasing from 2.2 between 1970 and 1989 to 13.7 between 2004 and 2007. Limitations Retrospective study; homogeneous population. Conclusion The incidence of LM increased significantly among residents of Olmsted County, Minnesota, over an extended time frame, with incidence being significantly higher among men than women and increasing with age.

A Retrospective Cohort Study on Patients with Lentigo Maligna Melanoma

“…The gender distribution of LMMs was controversial in previous studies [12, 20]. In the current study, only a slight tendency to male sex (56%) was observable.…”

“…Further, the head and neck region was the location with the highest incidence rate [12, 20, 21]. Since the sun-exposed body areas were more frequently affected, it seems quite evident that sun exposure is required for the progression of this type of tumor [22].…”

Imiquimod 5% cream as primary or adjuvant therapy for melanoma in situ, lentigo maligna type

“…[14][15][16] In an institutional analysis of the VAPAHCS Tumor Registry data from 2003 through 2013, LM accounted for 75.5% (237/314) of subtyped MIS cases and LMM for 46.2% (147/318) of invasive melanomas. Management of LM is complicated by its typical location on the head and neck in older individuals, in whom surgical options may be limited, and histologic difficulty in differentiating actinic melanocytic hyperplasia in chronically sun-damaged skin from true LM.…”

Lentigo Maligna and Lentigo Maligna Melanoma: Contemporary Issues in Diagnosis and Management

“…The mean age at diagnosis is 70 years [7]. Risk factors for the development of LM include history of sun exposure, light skin and propensity toward development of lentigines.…”

“…Risk factors for the development of LM include history of sun exposure, light skin and propensity toward development of lentigines. LM is most commonly found on the cheek (estimated at 26-48% of lesions) [7][8][9]. Unlike superficial spreading melanoma, LMM is more strongly associated with previous development of lentigines and skin cancer history, and is not associated with pre-existing nevi or propensity toward development of nevi [10,11].…”