Frequency of Microsatellite Metastases, Satellite Metastases, and Residual Tumor in Thin Melanomas: A Retrospective Cohort Study

Ebba Wennberg; Rudy Bittar; Helena Svensson; John Paoli

doi:10.5826/dpc.1502a5157

Frequency of Microsatellite Metastases, Satellite Metastases, and Residual Tumor in Thin Melanomas: A Retrospective Cohort Study

Authors

Ebba Wennberg Department of Dermatology and Venereology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden AND Department of Dermatology and Venereology, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden https://orcid.org/0009-0005-9871-2675
Rudy Bittar Department of Dermatology and Venereology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
Helena Svensson Department of Dermatology and Venereology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden AND Department of Dermatology and Venereology, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden https://orcid.org/0000-0001-6332-430X
John Paoli Department of Dermatology and Venereology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden AND Department of Dermatology and Venereology, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden https://orcid.org/0000-0003-1326-8535

Keywords:

Microsatellite metastases, satellite metastases, residual melanoma, thin melanoma, Wide local excision, invasive melanoma, dermatologic surgery

Abstract

Introduction: Thin invasive melanomas (Breslow thickness ≤1.0 mm) are increasing in incidence in Sweden, but also notably have a favorable prognosis. Treatment typically involves complete diagnostic excision followed by wide local excision (WLE) to eliminate potential microsatellite and satellite metastases, along with residual melanoma.

Objectives: This study aimed to investigate the frequency of microsatellite and satellite metastases in diagnostic excision specimens and residual melanoma in WLE specimens from thin melanomas.

Methods: This was a retrospective cohort study including consecutively collected primary thin melanomas excised at Sahlgrenska University Hospital between January 2014 and December 2020.

Results: Among 1,012 cases, no microsatellites were observed in the diagnostic excisions. Meanwhile, macroscopic satellite metastases were only present in 0.2% of the cases (n=2). Among 887 melanomas undergoing WLE with available data (87.6%), no microsatellites or satellite metastases were found in the extra tissue removed. Of the completely excised melanomas (n=936, 92.5%), only 0.2% (n=2) exhibited residual melanoma in the WLE.

Conclusions: Our findings align with previous studies suggesting that WLE may result in excessive and unnecessary treatment for completely excised thin melanomas. The requirement of performing WLEs following complete excision of thin melanomas needs to be reevaluated.

References

Regional Cancer Centres in Sweden [National Guidelines Malignant Melanoma]. Updated June 11, 2024. Accessed October 1, 2024. https://kunskapsbanken.cancercentrum.se/diagnoser/melanom/vardprogram/.

The Swedish Cancer Registry of the National Board of Health and Welfare. [Cancer statistics database]. Updated December 19, 2022. Accessed October 1, 2024. https://www.socialstyrelsen.se/statistik-och-data/statistik/alla-statistikamnen/cancer/.

Gershenwald JE, Scolyer RA, Hess KR, et al. Melanoma staging: Evidence-based changes in the American Joint Committee on Cancer eighth edition cancer staging manual. CA Cancer J Clin. 2017;67(6):472-92. DOI: 10.3322/caac.21409. PMID: 29028110.

Isaksson K, Mikiver R, Eriksson H, et al. Survival in 31 670 patients with thin melanomas: a Swedish population-based study. Br J Dermatol. 2021;184(1):60-7. DOI: 10.1111/bjd.19015. PMID: 32133615.

Zijlker LP, Eggermont AMM, van Akkooi ACJ. The end of wide local excision (WLE) margins for melanoma? Eur J Cancer. 2023;178:82-87. DOI: 10.1016/j.ejca.2022.10.028. PMID: 36423526.

McGoldrick RB, Ng D, Sawyer A, Mackey S, Vadodaria S, Powell BW. Malignant melanoma re-excision specimens: is there a need for histopathological analysis? J Plast Reconstr Aesthet Surg. 2008;61(8):983-4. DOI: 10.1016/j.bjps.2007.11.051. PMID: 18458016.

de Waal AC, Vossen R, Aben KK, Kiemeney LA, van Rossum MM, Blokx WA. Limited role for histopathological examination of re-excision specimens of completely excised melanomas. Virchows Arch. 2014;465(2):225-31. DOI: 10.1007/s00428-014-1595-5. PMID: 24869787.

Bolshinsky V, Lin MJ, Serpell J, et al. Frequency of residual melanoma in wide local excision (WLE) specimens after complete excisional biopsy. J Am Acad Dermatol. 2016;74(1):102-7. DOI: 10.1016/j.jaad.2015.08.065. PMID: 26601566.

Lau KL, Bradish T, Rannan-Eliya S. 'Primum non nocere': how harmless is routine wide local excision for AJCC stage IA melanoma? Ann R Coll Surg Engl. 2020;102(7):483-7. DOI: 10.1308/rcsann.2020.0050. PMID: 32233852.

Riquelme-Mc Loughlin C, Sandoval-Clavijo A, Blanco de Tord M, et al. Prognostic role of microsatellites in melanoma and implications in the American Joint Committee on Cancer classification system: A cohort study. J Am Acad Dermatol. 2023;88(2):338-47. DOI: 10.1016/j.jaad.2022.10.027. PMID: 36265824.

Kelly JW, Sagebiel RW, Calderon W, Murillo L, Dakin RL, Blois MS. The frequency of local recurrence and microsatellites as a guide to reexcision margins for cutaneous malignant melanoma. Ann Surg. 1984;200(6):759-63. DOI: 10.1097/00000658-198412000-00015. PMID: 6508406.

Azimi F, Scolyer RA, Rumcheva P, et al. Tumor-infiltrating lymphocyte grade is an independent predictor of sentinel lymph node status and survival in patients with cutaneous melanoma. J Clin Oncol. 2012;30(21):2678-83. DOI: 10.1200/JCO.2011.37.8539. PMID: 22711850.

Shaikh L, Sagebiel RW, Ferreira CM, Nosrati M, Miller JR, 3rd, Kashani-Sabet M. The role of microsatellites as a prognostic factor in primary malignant melanoma. Arch Dermatol. 2005;141(6):739-42. DOI: 10.1001/archderm.141.6.739. PMID: 15967920.

Day CL, Jr., Harrist TJ, Gorstein F, et al. Malignant melanoma. Prognostic significance of "microscopic satellites" in the reticular dermis and subcutaneous fat. Ann Surg. 1981;194(1):108-12. DOI: 10.1097/00000658-198107000-00019. PMID: 7247529.

Jackett LA, Satgunaseelan L, Roper E, Lo SN, Thompson JF, Scolyer RA. Residual melanoma in wide local excision specimens after 'complete' excision of primary cutaneous in situ and invasive melanomas. Pathology. 2022;54(1):71-8. DOI: 10.1016/j.pathol.2021.05.094. PMID: 34392983.

Weyers W. "Personalized Excision" of Malignant Melanoma-Need for a Paradigm Shift in the Beginning Era of Personalized Medicine. Am J Dermatopathol. 2019;41(12):884-96. DOI: 10.1097/DAD.0000000000001450. PMID: 31490196.

Haniff J, de Vries E, Claassen AT, Looman CW, van Berlo C, Coebergh JW. Non-compliance with the re-excision guidelines for cutaneous melanoma in The Netherlands does not influence survival. Eur J Surg Oncol. 2006;32(1):85-9. DOI: 10.1016/j.ejso.2005.09.009. PMID: 16289645.

Hanson J, Demer A, Liszewski W, Foman N, Maher I. Improved overall survival of melanoma of the head and neck treated with Mohs micrographic surgery versus wide local excision. J Am Acad Dermatol. 2020;82(1):149-55. DOI: 10.1016/j.jaad.2019.08.059. PMID: 31473297.

Demer AM, Hanson JL, Maher IA, Liszewski W. Association of Mohs Micrographic Surgery vs Wide Local Excision With Overall Survival Outcomes for Patients With Melanoma of the Trunk and Extremities. JAMA Dermatol. 2021;157(1):84-9. DOI: 10.1001/jamadermatol.2020.3950. PMID: 33084853.

Wennberg E, Claeson M, Olofsson Bagge R, Polesie S, Paoli J. Wise or wide (WoW) study protocol: a national, multicentre, prospective, randomised and controlled, parallel group, non-inferiority study to compare single-staged versus two-staged excisions of thin invasive (≤1.0 mm) melanoma. BMJ Open. 2025;15; e094544. DOI: 10.1136/bmjopen-2024-094544. PMID: 40180392.