Characteristics, treatment and outcomes of 589 melanoma patients documented by 27 general practitioners on the Skin Cancer Audit Research Database

Abstract

Background and objective: General practitioners manage more melanomas than dermatologists or surgeons in Australia. Previously undescribed, the management and outcomes of melanoma patients treated by multiple Australasian general practitioners are examined.

Methods: The characteristics, management and outcomes of 589 melanoma patients, managed by 27 Australasian general practitioners and documented on the Skin Cancer Audit Research Database (SCARD), were analysed.

Results: Most patients (58.9%) were males with mean age at diagnosis of 62.7 years (range 18-96), and most melanomas were in situ or thin-invasive. Patients aged under 40 years had fewer melanomas, but a higher proportion (the majority) were invasive, compared with older patients (P < 0.0001). Most (55.9%) melanomas were diagnosed following elliptical excision biopsy, the rate of unintended involved margins being eightfold higher for shave biopsies. Wide re-excision was performed by the treating general practitioner for most (74.9%) melanomas, with thick melanomas preferentially referred to surgeons. The average Breslow thickness of invasive melanomas re-excised by general practitioners was 0.67 mm compared with 1.99 mm for those referred to other specialists (P < 0.0001). Of 205 patients with invasive melanoma, 14 progressed to metastatic disease, 50% of these being associated with nodular melanoma. Nine patients progressed to melanoma-specific death. The 5-year survival rate for patients with invasive melanoma was 95.2% (95% CI: 91.2-98.5%).

Conclusions: Diagnostic and therapeutic management of a series of melanoma patients by Australasian general practitioners were closely aligned with current guidelines and 5-year survival with respect to invasive melanoma was at least as favourable as national population-based metrics.

Keywords: SCARD; general practice; general practitioner; melanoma; melanoma 5-year survival; melanoma management; melanoma outcomes; primary care.

Figure 1

Numbers of in situ and invasive melanomas by age. Exact counts are shown on corresponding bar segments. A single primary invasive melanoma with unknown thickness was excluded from this analysis. Statistical analysis to compare proportion of invasive and in situ melanomas for those aged under 40, or 40 and over, were performed using a Fisher's exact test. [Colour figure can be viewed at wileyonlinelibrary.com]

Figure 2

Practitioners providing the definitive treatment (secondary wide excision) of in situ and invasive melanomas. Exact counts are shown above the corresponding bar. A single primary invasive melanoma with unknown thickness was excluded from this analysis. Abbreviations: GP, general practitioner; WLE, wide local excision. [Colour figure can be viewed at wileyonlinelibrary.com]

Figure 3

Details of outcomes for 205 patients with at least one primary invasive melanoma in 2013. Details of each segment are presented in adjacent text. One patient with a primary invasive melanoma of unknown Breslow thickness was excluded from analysis (sentinel lymph node biopsy negative, negative for metastases and surviving). Abbreviations: SLNB, sentinel lymph node biopsy; LNMet, lymph node metastasis; DMet, distant metastasis; IntransitMet, in‐transit cutaneous metastasis. [Colour figure can be viewed at wileyonlinelibrary.com]