Digital Follow-up of Acral Melanocytic Nevi
Altamura D, Zalaudek I, Sera F, et al
Arch Dermatol. 2007;143:1372-1376
Although most dermatologists are experienced at differentiating benign pigmented melanocytic nevi from dysplastic melanocytic nevi and melanomas, acral melanocytic nevi (AMN) can be more challenging to assess. In part this may be because there is a paucity of published data outlining the typical dermoscopic patterns found in AMN. In an attempt to fill this void, Altamura and colleagues conducted a large retrospective review of common dermoscopic patterns and changes observed in a series of acquired acral melanocytic nevi (AAMN).
This study included digital dermoscopic images from 230 AAMN located on the soles (n = 149), fingers (n = 62), and palms (n = 19) of 230 white patients of Italian descent (mean age: 24.4 years; 58.7% male). Investigators reviewed digital dermoscopic images of AAMN taken at 6-, 12-, 18-, and 24-month intervals, making note of baseline dermoscopic patterns and any changes that occurred during follow-up. Investigators noted the following baseline dermoscopic features of benign AAMN, which have been previously described in both Asian and white patients:
During the follow-up period, dermoscopic changes were noted in 42 AAMN (18.3%), with patients younger than 14 years showing the greatest frequency of change (28.4%). In addition, nevi showing the parallel-furrow pattern showed greater variability over time (6 to 24 months) than did other dermoscopic patterns. Changes in dermoscopic patterns increased over time, with 32.1% of nevi showing changes after 24 months (vs only 8.5% of nevi after 6 months). Furthermore, AAMN in the pediatric population were most dynamic, showing changing dermoscopic patterns in 50% of nevi after a follow-up of 2 years. Seven of the acral nevi in the study showed decreased pigmentation over time, and 4 of these showed a light brown, "homogeneous" pattern, which the authors suggest is a feature of benign involution. No patients in the study population developed the "parallel ridge" or "diffuse irregular pigmentation" patterns characteristic of acral malignant melanoma, and histopathologic evaluation of 20 surgically excised AAMN showed benign features.
Dermoscopic analysis can be used to distinguish benign from suspicious AMN. In the above retrospective analysis, Altamura and colleagues describe common dermoscopic patterns of AAMN in a white Italian patient population, and confirm that these nevi are dynamic pigmented lesions that often change over time, especially in younger subjects. Care should be taken before generalizing the results from a fairly homogeneous white population, and future studies should explore whether the observations reported by Altamura and colleagues apply to other ethnic and racial groups. Nevertheless, the observations provide a useful template for assessing AAMN and should reassure clinicians that the observed pigment patterns are quite dynamic over time, especially in younger patients.
Abstract
Altamura D, Zalaudek I, Sera F, et al
Arch Dermatol. 2007;143:1372-1376
Although most dermatologists are experienced at differentiating benign pigmented melanocytic nevi from dysplastic melanocytic nevi and melanomas, acral melanocytic nevi (AMN) can be more challenging to assess. In part this may be because there is a paucity of published data outlining the typical dermoscopic patterns found in AMN. In an attempt to fill this void, Altamura and colleagues conducted a large retrospective review of common dermoscopic patterns and changes observed in a series of acquired acral melanocytic nevi (AAMN).
This study included digital dermoscopic images from 230 AAMN located on the soles (n = 149), fingers (n = 62), and palms (n = 19) of 230 white patients of Italian descent (mean age: 24.4 years; 58.7% male). Investigators reviewed digital dermoscopic images of AAMN taken at 6-, 12-, 18-, and 24-month intervals, making note of baseline dermoscopic patterns and any changes that occurred during follow-up. Investigators noted the following baseline dermoscopic features of benign AAMN, which have been previously described in both Asian and white patients:
Parallel-furrow pattern (48.7%);
Latticelike pattern (15.2%);
Fibrillar pattern (10.8%);
Nontypical pattern (10.8%);
Homogeneous pattern (4.8%);
Transition pattern (3.5%); and
Reticular pattern (2.6%).
During the follow-up period, dermoscopic changes were noted in 42 AAMN (18.3%), with patients younger than 14 years showing the greatest frequency of change (28.4%). In addition, nevi showing the parallel-furrow pattern showed greater variability over time (6 to 24 months) than did other dermoscopic patterns. Changes in dermoscopic patterns increased over time, with 32.1% of nevi showing changes after 24 months (vs only 8.5% of nevi after 6 months). Furthermore, AAMN in the pediatric population were most dynamic, showing changing dermoscopic patterns in 50% of nevi after a follow-up of 2 years. Seven of the acral nevi in the study showed decreased pigmentation over time, and 4 of these showed a light brown, "homogeneous" pattern, which the authors suggest is a feature of benign involution. No patients in the study population developed the "parallel ridge" or "diffuse irregular pigmentation" patterns characteristic of acral malignant melanoma, and histopathologic evaluation of 20 surgically excised AAMN showed benign features.
Dermoscopic analysis can be used to distinguish benign from suspicious AMN. In the above retrospective analysis, Altamura and colleagues describe common dermoscopic patterns of AAMN in a white Italian patient population, and confirm that these nevi are dynamic pigmented lesions that often change over time, especially in younger subjects. Care should be taken before generalizing the results from a fairly homogeneous white population, and future studies should explore whether the observations reported by Altamura and colleagues apply to other ethnic and racial groups. Nevertheless, the observations provide a useful template for assessing AAMN and should reassure clinicians that the observed pigment patterns are quite dynamic over time, especially in younger patients.
Abstract