METHODS: This is a retrospective non-randomized study of outcomes and tumor recurrence of all patients diagnosed with mandibular ameloblastoma from August 1997 until August 2017 (20 years) requiring free fibula osteocutaneous flap reconstruction at a single institution. The patients were identified through an electronic operative database; subsequently, their medical records and photo documentation were retrieved.
RESULTS: Twenty-seven patients were included in this study. Eighteen patients were male, while nine were female. The majority of the patients (48.1%) were in their third decade of life when they were diagnosed with ameloblastoma. All of them underwent radical resection of the tumor with a surgical margin of 2 cm (hemimandibulectomy in cases with a large tumor) and immediate mandibular reconstruction with a free fibula osteocutaneous flap. Two patients required revision of a vascular anastomosis due to venous thrombosis postoperatively, while one patient developed a flap recipient site infection. The flap success rate was 100%. There was no tumor recurrence during a mean follow-up period of 5.6 years.
CONCLUSIONS: Mandibular ameloblastoma should be treated with segmental mandibulectomy (with a surgical margin of 2 cm) to reduce the risk of recurrence. Subsequent mandibular and adjacent soft tissue defects should be reconstructed immediately with a free fibula osteocutaneous flap.
METHODS: We conducted a comprehensive search of published articles in Cochrane Library, Pubmed, and Science-Direct to identify relevant randomized controlled trials (RCTs) and observational studies comparing IAC alone or combined with IVC versus IVC/BCG alone in NMIBC. The protocol of preferred reporting items for systematic review and meta-analysis (PRISMA) was applied to this study.
RESULTS: Four RCTs and 4 cohort observational studies were eligible in this study and 5 studies were included in meta-analysis. The risk ratio of tumor recurrence was reduced by 35% (RR = 0.65; 95% CI 0.49-0.87; p = 0.004) in IAC plus IVC, while recurrence-free survival (RFS) was prolonged by 45% (HR: 0.55; 95% CI, 0.44-0.69; p < 0.001). The risk of tumor progression was reduced by 45% (RR = 0.55; 95% CI 0.41-0.75; p = 0.002) and tumor progression-free survival (PFS) was also prolonged by 53% (HR: 0.47; 95% CI, 0.34-0.65; p<0.001). Some RCT's had high or unclear risk of bias, meanwhile 4 included cohort studies had overall low risk of bias, therefore the pooled results need to be interpreted cautiously. Subgroup analysis revealed that the heterogeneity outcome of tumour recurrence might be attributed to the difference in NMIBC stages and grades.
CONCLUSIONS: The IAC alone or combined with IVC following bladder tumor resection may lower the risk of tumor recurrence and progression. These findings highlight the importance of further multi institutional randomized controlled trials with bigger sample size using a standardized IAC protocol to validate the current results.