Background

Oral squamous cell carcinoma (OSCC) is the 15th most common cause of cancer-related mortality worldwide and approximately one oral cancer-related death occurs for every two new diagnoses. Death-due-to-disease is usually ascribed to inoperable primary tumours, treatment complications, second primary tumours arising due to field cancerization, or locoregional recurrence and distant metastases.

Methods

A retrospective review of OSCC patients treated over a 19-year period, betweenOctober 1st, 2000 and October 1st, 2019. Patient demographic records were collected from consecutively treated adult patients with clinical subtypes corresponding to ICD-10 C00-C06, C09 and C10 were retrieved from the database. Patients who had suffered three or more recurrences after diagnosis of the primary tumour are defined as multiple-recurrent patients.

Results

A total of 467 OSCC patients were treated during the study period. One hundred and fifty-five patients developed recurrent OSCC, amongst which 22 were designated as multiple cases. The time between initial OSCC diagnosis and first tumour recurrence varied from 3 to 276 months. Nine of the 22 multiple patients (41%) were diagnosed with buccal mucosal SCC as the primary tumour, which is significantly higher than the average prevalence (or 4.4, 95% CI (1.8, 10.8), p < 0.001) for buccal tumours within the cohort.

All patients were treated initially by surgical tumour excision. There were no demonstrable differences in adjuvant chemo-radiotherapy regimes in any of the study groups.

Conclusion

Multiple OSCC development may occur either synchronously or metachronously during the course of oral cancer disease and poses an important management problem in contemporary oncology practice.