Marginal and segmental mandibulectomy in patients with oral cancer: a statistical analysis of 106 cases.
OBJECTIVE
The treatment of oral squamous cell carcinoma may require mandibular resection to secure adequate margin. This bone resection often is segmental or marginal mandibulectomy. The purpose of this work was to evaluate the local control and survival after surgical treatment of oral cancer, according to these 2 different mandibular resection procedures.


METHODS
We conducted a retrospective study of a 20-year cohort of 106 patients who underwent marginal or segmental mandibulectomy for oral cancer. All patients had a biopsy-confirmed diagnosis of squamous cell carcinoma involving either the floor of the mouth, mandibular gingiva, retromolar trigone, tongue, buccal mucosa, or oropharynx. The type of mandibular resection and treatment outcome were compared, using an univariate analysis by the Pearson chi(2) test, logistic regression model for multivariate analysis, and Kaplan-Meier method to determine survival.


RESULTS
The 5-year observed survival rate was 60.35%. The presence of histologic mandibular invasion increased the local recurrence rate. Early tumor stages (P =.02) were found to be associated with decreased local recurrence rates. Our findings indicate that tumor stage and size of mandibulectomy are more important than the type of mandibulectomy in predicting histologic bone involvement. The cases treated with a greater than 4 cm bone resection showed a lower survival rate than those treated with less than 4 cm mandibulectomy (P =.01). Patients in advanced stages (P =.006) and those with surgical margin (P =.0001) or the bone (P =.003) affected by the tumor showed a statistically significant lower survival rate. However, no statistically significant differences were found between patients treated by marginal or segmental mandibulectomy.


CONCLUSIONS
Among the prognostic factors studied, the status of the surgical resection margin, the bony involvement and the size of mandibulectomy affected the prognosis for oral carcinoma. Mandibular conservation surgery is oncologically safe for patients with squamous carcinoma in early stages. The marginal technique was not associated with worse prognosis.
Muñoz Guerra
Mario Fernando
MF
Department of Oral and Maxillofacial Surgery, University Hospital La Princesa, Autónoma University, C/General Ricardos no. 171, 2B, 28025 Madrid, Spain. maxmferm@excite.com
Naval Gías
Luis
L
Campo
Francisco Rodríguez
FR
Pérez
Jesús Sastre
JS
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002294:Carcinoma, Squamous Cell / Q000601:surgery*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008334:Mandible / Q000601:surgery*; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000601:surgery*; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009367:Neoplasm Staging; D010027:Osteotomy / Q000145:classification / Q000706:statistics & numerical data; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome