IMMEDIATE FREE FLAP MANDIBULAR RECONSTRUCTION - SIGNIFICANCE OF ADEQUATE SURGICAL MARGINS

The pathologic records of 182 consecutive patients who had mandible re sections were reviewed to determine the incidence of positive margins in the bone specimens and the risk factors associated with positive ma rgins. Of the 182 cases reviewed, 82 (45%) were found to have involvem ent of the mandible at the time of resection and four (2%) were found to have positive margins. The predominant tumor histology was squamous cell carcinoma, 148 of 182 (81%), followed in frequency by osteosarco ma 12 of 182 (7%), salivary gland tumors 13 of 182 (7%), and miscellan eous other tumors (nine of 182 (5%). Of the four tumors with positive margins, two (50%) were squamous cell carcinomas, one (25%) was an ost eosarcoma, and one (25%) was a salivary gland tumor. All four tumors w ere large tumors that had failed to respond to previous therapy. All o bviously involved the mandible at the time of presentation. This study demonstrates that the incidence of bone margin involvement after mand ibulectomy is rare and predictable and that clinical selection of cand idates for immediate reconstruction is reliable in preventing inapprop riate use of free bone flaps in patients at risk for positive bone mar gins.