Growth rate of melanoma in vivo and correlation with dermatoscopic and dermatopathologic findings

Jürgen Beer; Lina Xu; Philipp Tschandl; Harald Kittler

doi:10.5826/dpc.0101a13

Growth rate of melanoma in vivo and correlation with dermatoscopic and dermatopathologic findings

Authors

Jürgen Beer Department of Dermatology, Division of General Dermatology, Medical University of Vienna, Austria
Lina Xu Department of Dermatology, Division of General Dermatology, Medical University of Vienna, Austria
Philipp Tschandl Department of Dermatology, Division of General Dermatology, Medical University of Vienna, Austria
Harald Kittler Department of Dermatology, Division of General Dermatology, Medical University of Vienna, Austria

Keywords:

horizontal growth rate, melanoma in vivo, dermatoscopy

Abstract

Objectives: The aim of this study was to calculate the horizontal growth rate of melanoma in vivo and to correlate it with morphologic findings.

Patients and Methods: We searched our database for melanomas for which sequential dermatoscopic images and histopathologic slides were available. The final sample consisted of 50 melanomas of 48 patients (mean age: 50 ± 15 years, 62% females). We calculated the horizontal growth rate in mm2 per year by morphometric analysis of digital dermatoscopic images. Dermatoscopic and dermatopathologic findings were assessed according to predefined criteria and correlated with the horizontal growth rate.

Results: The median time interval between baseline and follow-up image was 12 months (range: 2-100 months). The majority of melanomas were in situ (n=28, 56%). The mean horizontal growth rate of all melanomas was 5.3 mm2/year (SD: ± 5.8 mm2/year). The histopathologic findings of numerous and large epidermal nests were associated with rapid growth. This histopathologic pattern corresponded to a pattern of clods (“globules”) dermatoscopically. From a dermatoscopic point of view, melanomas with a main pattern of clods grew significantly faster (mean horizontal growth rate: 10.4 mm2/year, 95% CI: 6.4-14.4 mm2/year) than melanomas with mainly a reticular pattern (4.8 mm2/year, 95% CI: 2.7-7.0 mm2/year) or with other patterns (2.6 mm2/year, 95% CI: -0.5-5.6 mm2/year, p=0.01).

Conclusion: Morphologic characteristics of melanoma are associated with biologic behavior. Large and numerous epidermal nests (corresponding to a pattern of clods dermatoscopically) indicate more rapid growth.

References

1. Clark WH Jr, From L, Bernardino EA, Mihm MC. The histogenesis and biologic behavior of primary human malignant melanomas of the skin. Cancer Res 1969;29(3):705-27.

2. Grob JJ, Richard MA, Gouvernet J, et al. The kinetics of the visible growth of a primary melanoma reflects the tumor aggressiveness and is an independent prognostic marker: a prospective study. Int J Cancer 2002;102(1):34-8.

3. Liu W, Dowling JP, Murray WK, et al. Rate of growth in melanomas: characteristics and associations of rapidly growing melanomas. Arch Dermatol 2006;142(12):1551-8.

4. Kittler H. Dermatoscopy: introduction of a new algorithmic method based on pattern analysis for diagnosis of pigmented skin lesions. Dermatopathology: Practical & Conceptual 2007;13(1):3.

5. Viros A, Fridlyand J, Bauer J, et al. Improving melanoma classification by integrating genetic and morphologic features. PLoS Med 2008;5(6):e120.

6. Argenziano G, Kittler H, Ferrara G, et al. Slow-growing melanoma: a dermoscopy follow-up study. Br J Dermatol 2010;162(2):267-73.