Abstract
Introduction
In 2009, the American Joint Committee on Cancer (AJCC) incorporated the tumor mitotic rate in the melanoma pathological TNM staging system. To investigate the effect of this change on the pT1 substaging of primary cutaneous melanomas, we reclassified the cases collected by a cancer registry according to the 6th and the 7th editions of AJCC melanoma staging.
Methods
Patients with pathological T1 melanoma diagnosed in the period 2000–2008 were selected from Tuscan Cancer Registry. The histological reports were reviewed and pT1 melanomas classified according to both the 6th and the 7th editions of the AJCC staging system. The shift of melanomas between pT1 substages was analyzed.
Results
Among the 242 pT1 melanomas collected in the study period and with mitotic index available, there were 202 (83 % of all pT1) and 175 (72 %) pT1a, according to the 6th and the 7th editions of the AJCC melanoma staging, respectively. When the 7th edition was used, 20 % of all pT1a melanomas shifted to pT1b, and 32 % of all pT1b melanomas shifted to pT1a. A poor level agreement between the two TNM staging systems, measured by the Cohen’s kappa coefficient, was found (K = 0.37).
Conclusions
The addition of mitotic activity to the pathological staging resulted in an increase in pT1b proportion and in a change in the classification of some cases. This modification could influence the clinical approach, with a different use of the sentinel lymph node biopsy, and underlines the role of mitosis evaluation in the management of thin melanoma patients.
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References
Azzola MF, Shaw HM, Thompson JF, Soong SJ, Scolyer RA, Watson GF, Colman MH, Zhang Y (2003) Tumor mitotic rate is a more powerful prognostic indicator than ulceration in patients with primary cutaneous melanoma: an analysis of 3661 patients from a single center. Cancer 97:1488
Balch CM, Gershenwald JE, Soong SJ, Thompson JF, Atkins MB, Byrd DR, Buzaid AC, Cochran AJ, Coit DG, Ding S, Eggermont AM, Flaherty KT, Gimotty PA, Kirkwood JM, McMasters KM, Mihm MC Jr, Morton DL, Ross MI, Sober AJ, Sondak VK (2009) Final version of 2009 AJCC melanoma staging and classification. J Clin Oncol 27:6199
Balch CM, Gershenwald JE, Soong SJ, Thompson JF (2011) Update on the melanoma staging system: the importance of sentinel node staging and primary tumor mitotic rate. J Surg Oncol 104:379–385
Burton AL, Egger ME, Gilbert JE, Stromberg AJ, Hagendoorn AJ, Martin RC, Scoggins CR, McMasters KM, Callender GG (2012) Assessment of mitotic rate reporting in melanoma. Am J Surg 204(6):969–974
Caudle AS, Ross MI, Prieto VG (2010) Mitotic rate predicts sentinel lymph node involvement in melanoma: impact of the 7th edition AJCC Melanoma Staging System. Ann Surg Oncol 17(suppl 1):S8
Chu VH, Tetzlaff MT, Torres-Cabal CA, Prieto VG, Basset R Jr, Gershenwald JE, McLemore MS, Ivan D, Wang WL, Ross MI, Curry JL (2013) Impact of the 2009 (7th Edition) AJCC melanoma staging system in the classification of thin cutaneous melanomas. Biomed Res Int. doi:10.1155/2013/898719
de Waal AC, van Harten-Gerritsen AS, Aben KKH, Kiemeney LALM, van Rossum MM, Blokx WAM (2014) Impact of mitotic activity on the pathological substaging of pT1 cutaneous melanoma. Br J Dermatol 170:874–877
Dickinson PV, Gershenwald E (2011) Staging and prognosis of cutaneous melanoma. Surg Oncol Clin N Am 20(1):1–17
Eggermon AMM, Spatz A, Robert C (2014) Cutaneous melanoma. Lancet 383:816–827
Gimotty PA, Elder DE, Fraker DL, Botbyl J, Sellers K, Elenitsas R, Ming ME, Schuchter L, Spitz FR, Czerniecki BJ, Guerry D (2007) Identification of high-risk patients among those diagnosed with thin cutaneous melanomas. J Clin Oncol 25:1129–1134
Hieken TJ, Grotz TE, Comfere NI, Inselman JW, Habermann EB (2015) The effect of the AJCC 7th edition change in T1 melanoma substaging on national utilization and outcomes of sentinel lymph node biopsy for thin melanoma. Melanoma Res 25(2):157–163
Ivan D, Prieto VG (2011) An update on reporting histopathologic prognostic factors in melanoma. Arch Pathol Lab Med 135:825–829
Knezevich SR, Barnhill RL, Elder DE, Piepkorn MW, Reisch LM, Pocobelli G, Carney PA, Elmore JG (2014) Variability in mitotic figures in serial sections of thin melanomas. J Acad Dermatol. doi:10.1016/j.jaad.2014.07.056
Mozzillo N, Pennacchioli E, Gandini S, Caracò C, Crispo A, Botti G, Lastoria S, Berberis M, Verrecchia F, Testori A (2013) Sentinel node biopsy in thin and thick melanoma. Ann Surg Oncol 20(8):2780–2786. doi:10.1245/s10434-012-2826-0
Murali R, Haydu LE, Quinn MJ, Saw RP, Sahnnon K, Spillane AJ, Stretch JR, Thompson JF, Scolyer RA (2012) Sentinel lymph node biopsy in patients with thin primary cutaneous melanoma. Ann Surg 255(1):128–133. doi:10.1097/SLA.0b013e3182306c72
Scolyer RA, Shaw HM, Thompson JF, Li LX, Colman MH, Lo SK, McCarthy SW, Palmer AA, Nicoll KD, Dutta B, Slobedman E, Watson GF, Stretch JR (2003) Interobserver reproducibility of histopathologic prognostic variables in primary cutaneous melanomas. Am J Surg Pathol 27:1571–1576
Sekul Gibbs SA, Shearer MA (2011) Sentinel lymph node biopsy should be offered in thin melanoma with mitotic rate greater than one. Dermatol Surg 37:1080–1088
Thompson JF, Soong SJ, Balch CM, Gershenwald JE, Ding S, Coit DG, Flaherty KT, Gimotty PA, Johnson T, Johnson MM, Leong SP, Rossmi Byrd DR, Cascinelli N, Cochran AJ, Eggermot AM, McMasters KM, Mihm MC Jr, Morton DL, Sondak VK (2011) Prognostic significance of mitotic rate in localized primary cutaneous melanoma: an analysis of patients in the multi-institutional American joint committee on cancer melanoma staging database. J Clin Oncol 29:2199–2205
Wong L, Brady MS, Busam KJ, Coit DG (2006) Results of sentinel lymph node biopsy in patients with thin melanoma. Ann Surg Oncol 13(3):302–309
Acknowledgments
The authors thank the ITT-MelaPat group (Tuscan pathologists dedicated to melanoma pathology).
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Caldarella, A., Fancelli, L., Manneschi, G. et al. How staging of thin melanoma is changed after the introduction of TNM 7th edition: a population-based analysis. J Cancer Res Clin Oncol 142, 73–76 (2016). https://doi.org/10.1007/s00432-015-2007-1
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DOI: https://doi.org/10.1007/s00432-015-2007-1