Incomplete primary excision of cutaneous basal and squamous cell carcinomas in the Bay of Plenty

To investigate factors associated with pathologically reported incomplete primary excision of squamous and basal cell carcinomas.

All Medlab Bay of Plenty histology reports were obtained for all primarily excised cutaneous basal and squamous cell carcinomas of the skin for the Tauranga and Western Bay of Plenty regions covering the period 1 January through 30 June 2001. Data were analysed according to surgical training, site of lesion, pathology, and location of positive margin involvement.

1833 non-melanoma skin cancer excisions occurred during the 6-month study-including 1126 basal cell carcinomas, 705 squamous cell carcinomas, and 2 basosquamous carcinomas. 257 (14%) were reported as incompletely excised. There was no difference in rates of positive margin involvement for gender or histology. Proportionately, excisions from the nose and ear revealed the highest incomplete excision rates. General practitioners excised 1003 lesions, with a 16% incomplete excision rate. Consultant surgeons excised 695 lesions, with a 12% incomplete excision rate. Surgical registrars excised 123 lesions, incompletely excising 8%. These data are statistically significant (p <0.01). Tumour was most often found at lateral (rather than deep) margins.

The incidence of non-melanoma skin cancer is known to be very high in the Bay of Plenty. Pathologically reported incomplete excision rates are nevertheless comparable with other studies. Of all skin cancers, those on the head and neck are most commonly associated with incomplete excision. Trained surgeons have significantly higher complete excision rates.