Quality assessment of a large primary GP skin cancer service in Auckland, New Zealand.

AIM: Waitemata District Health Board has implemented a new approach to the management of skin cancers by triaging lesions to specialist-trained general practitioners (GPSI) with the aim of reducing patient wait times and treatment costs. The primary outcome was to determine positive margin rates for the GP surgeons, with secondary outcome being infection rates. METHOD: A retrospective audit was conducted on all excisions (n=2,705) performed between 1 January 2016 and 31 December 2016 by the 13 WDHB GPSIs. Electronic patient records were accessed to review data. Each lesion was classified into benign, in-situ (pre-malignant) and malignant categories. Surgical margins were analysed for non-melanotic skin cancers (NMSC) and determined as positive, close or negative. Infection rates determined by microbiology results and prescribing information and time to treat analyses were conducted. RESULTS: WDHB GPSIs performed 2,705 excisions, 1,887 (69.8%) of which were malignant lesions. Among the 1,486 NMSC excised, a positive surgical margin was observed in 51 (3.4%). There were 294 (10.9%) cases of infection in 2,705 excisions. Median time to treat was 31 days across all lesions. New Zealand papers from the last two decades estimate the NMSC positive margin rate among primary care physicians varies between 16-31%; most recent papers have published rates 6.8-9.5%.European publications describe positive margin rates ranging between 13.9-33.5%. CONCLUSION: This study validates the use of surgically trained GP surgeons and shows their integral role in managing the high volume of skin cancer in New Zealand.

Quantitative assessment of Langerhans cells in actinic keratosis, Bowen's disease, keratoacanthoma, squamous cell carcinoma and basal cell carcinoma.

The quantitative distribution of Langerhans cells (LC) was studied in a range of pre-neoplastic, in-situ and invasive neoplastic skin lesions using an antibody to S100 protein and the indirect immunoperoxidase technique. LC numbers were increased within the lesions of actinic keratosis, Bowen's disease, keratoacanthoma, squamous cell carcinoma and basal cell carcinoma. In all lesions except actinic keratosis the LC density was also significantly increased in the adjacent non-neoplastic epithelium. The increased LC density in neoplastic epithelium suggests either that LC are being retained within the abnormal epithelium for longer periods of time than normal or that increased numbers of LC are being actively attracted by factors produced by the neoplastic epithelium. While reduction of intraepithelial LC density may allow the initiation of neoplasia the increased density observed in this study suggests that at later stages of tumour growth LC may have a functional role in the host response to cutaneous neoplasia.