Basal cell carcinoma (BCC) is the most common skin cancer worldwide and represents 75% of cutaneous malignancies (1). The mortality rate from BCCs is <1% and metastases rarely occur (0.0028% to 0.5%) (2-6). Achieving clear margins, particularly with the more aggressive histological subtypes of BCC and in recurrent tumours, can prove challenging. In these scenarios, the visible clinical margin frequently underestimates the true extent of the tumour. This phenomenon is often referred to as subclinical tumour growth with fingerlike extensions. It is particularly common in the danger zone of the face (H zone), where BCCs often behave more aggressively and recur more frequently (7,8).Before reconstruction, it is imperative that the entire BCC be removed with negative pathological margins. Incomplete resection of primary and recurrent tumours can lead to substantial morbidity and even mortality (9). The majority of BCCs can be treated using standard techniques including conventional surgical excision, curettage, cryotherapy and radiotherapy. The recurrence rates for each of these techniques has been reported to be 3% to 42% following surgical excision (10-12), 3% to 9% with curettage (13,14), 4% to 17% following cryotherapy (10) and 7% to 10% after radiation (15).Mohs micrographic surgery (MMS) or frozen section have been recommended for difficult tumours such as recurrent tumours, tumours located in anatomically sensitive areas, aggressive histological subtypes, perineural invasion or large tumours >2 cm in size (7). Cure rates with MMS has proven better than with other treatment modalities, with low overall five-year recurrence rates of 0.6% to 3% for primary BCC, and 6% to 10% for recurrent . Disadvantages of MMS include the fact that it can be very time consuming, expensive and the reconstruction may be deferred if the Mohs surgeon is not comfortable with more involved reconstructive procedures.We evaluated the effectiveness of a surgeon-directed 'en face' frozen section technique that immediately evaluates the entire peripheral and deep margins during BCC resection and potentially offers a more efficient and equally effective alternative to MMS.
METHODS PatientsThe study group comprised 50 patients who were treated by a single plastic surgeon (TH) in a tertiary centre. Fifty-three BCCs were evaluated. All tumours excised from the face over a five-year period (2002 to 2006) were retrospectively reviewed. The indications for 'en face' frozen section were recurrent tumours, tumours located in anatomically sensitive areas, aggressive histological subtypes, perineural invasion or large tumours >2 cm. The 'en face' method is a technique that permits examination of the entire tumour margin (20). The sections for the 'en face' method are cut very thin to enable maximal tissue preservation. Basal cell carcinomas (BCCs) of the head and neck treated by conventional techniques of surgical excision, curettage, cryotherapy and radiation therapy have recurrence rates of up to 42%. Mohs micrographic surgery (MMS) decreases the r...