Evaluation Of Primary Treatment Technique For Squamous Cell Carcinoma Of The Buccal Mucosa: A Single-Center Experience

Squamous cell carcinoma of the buccal mucosa is an uncommon oral cancer with a high rate of local recurrence. The purpose of this analysis is to review an institutional policy favoring primary radiation for thick/advanced tumors on functional and cosmetic grounds. We retrospectively reviewed the charts of patients treated for buccal mucosa cancer with curative intent at a single tertiary care cancer center between January 1990 and April 2013 under an IRB approved protocol. Patients were assessed using univariate and multivariate analyses. Local regional control (LRC), progression-free survival (PFS), and overall survival (OS) were analyzed utilizing the Kaplan-Meier method. Fifty-five patients met the inclusion criteria, 32 (58%) of whom were treated with primary surgery. Twenty-three (42%) were treated initially with radiation therapy (RT). Neither age (p = 0.30), stage (p = 0.99), ≥ 10-pack year smoking history (p = 0.44), nor use of chronic mouth irritants (betel nut/alcohol use > 7 drinks a week/smokeless tobacco) differed (p = 0.78) among treatment groups. Half (n = 16, 50%) of patients treated with primary surgery received adjuvant radiation (median 60, range 34 - 68.25 Gy) according to conventional indications. Patients treated with primary radiation with curative intent received a median dose of 70 (range 34 - 70) Gy, with radiosensitizing systemic therapy (n = 9, 39%), interstitial brachytherapy (n = 4, 17%), or external beam radiation alone (n = 10, 44%). LRC was not significantly influenced by treatment modality (primary surgery: 65%, primary radiation: 50%; p = 0.30), ≥ 10-pack year smoking history (p = 0.99), stage (p = 0.16), chronic mouth irritants (p = 0.40) or age (p = 0.55). By contrast, treatment with primary surgery had a significant PFS (p = 0.0024) and OS benefit (p = 0.05). Earlier stage had a similar PFS (p = 0.0003) and OS benefit (p = 0.0003). On multivariate analysis, the PFS benefit of treatment with primary surgery (p = 0.019) and for early stage tumors persisted (p = 0.003). The benefit of surgery was largely confined to patients with stage I/II disease, with a PFS of 100% at two years (p = 0.016). By contrast, the two year PFS of patients managed with primary surgery for stage III/IV tumors (33%), primary radiation for stage I/II tumors (46%), and primary radiation for stage III/IV tumors (18%) was poor. Most recurrences were local (24/26, 92%). Thirteen patients submitted to salvage surgery for recurrence survived 1.8 years (range 0.29 - 4.56). Select T1-T2 N0 buccal mucosa cancers do well when managed with primary surgery. By contrast, advanced tumors (Stage III/IV) requiring combined modality therapy and Stage I/II tumors managed with primary RT did not do well.