Lip-split Mandibulectomy Versus Lip-mandible Preservation Technique for Oral and Oropharyngeal Cancer: a Systematic Review and Meta-analysis of Comparative Studies.

Background: Many studies have compared lip-splitting mandibulotomy (LSM) and lip-mandible preservation (LMP) techniques in oral and oropharyngeal cancer (OOPC) patients with inconsistent conclusions. Evidence-based recommendations for the optimal surgical approach for treating OOPC are lacking.

Methods: The Cochrane Library, Pubmed, Embase, Web of Science, WAN-FANG, CQVIP, and China National Knowledge Infrastructure were systematically searched to identify studies that compared LSM versus LMP for OOPC. An additional search of the gray literature was performed using Google Scholar, OpenGrey and ProQuest Dissertations & Theses Global.Survival rate, recurrence rate, surgical margin, perioperative outcomes, postoperative complications and functional status were assessed. The standard mean difference (SMD) and odds ratio (OR) with a 95% CI were pooled using fixed-effect or random-effect models.

Results: Four randomized controlled trials, five case-control studies and twenty cohort studies including a total of 2622 patients were identified. The LSM approach significantly increased postoperative complications such as mandibular osteomyelitis/osteoradionecrosis (OR = 4.57; 95% CI = 1.20 ~ 17.39; p = 0.026), fistula (OR = 1.5; 95% CI = 1.05 ~ 2.15; p = 0.027), and flap infection (OR = 2.96; 95% CI = 1.49 ~ 5.87; p = 0.002), while LMP improved facial appearance (SMD = -0.65; 95% CI = -1.05 ~-0.25; p = 0.002). Meta-analyses showed no significant difference in survival rate (OR = 1.07; 95% CI = 0.83 ~ 1.38; p = 0.59), total recurrence (OR = 1.15; 95% CI = 0.87 ~ 1.52; p = 0.325), local recurrence (OR = 1.39; 95% CI = 0.88 ~ 2.19; p = 0.163), operation duration (SMD = 0.19; 95% CI = -0.75 ~ 1.13; p = 0.688), length of hospital stay (SMD = 0.48; 95% CI = -0.27 ~ 1.22; p = 0.208), volume of blood loss (SMD = 0.43; 95% CI = -0.17 ~ 1.03; p = 0.156), surgical margin (OR = 1.01; 95% CI = 0.72 ~ 1.41; p = 0.947), hematoma/seroma (OR = 1.01; 95% CI = 0.46 ~ 2.25; p = 0.972), wound infection (OR = 1.28; 95% CI = 0.92 ~ 1.79; p = 0.145), swallowing (SMD = -0.33; 95% CI = -0.91 ~ 0.24; p = 0.428) and speech (SMD = -0.14; 95% CI = -0.44 ~ 0.17; p = 0.381) between the LSM and LMP groups.

Conclusion: These findings suggest that LMP may be a safe and efficient alternative to LSM for treating OOPC patients with decreased mandibular osteomyelitis/osteoradionecrosis, fistula, flap infection, and a better aesthetic outcome.