Background: The aim of this retrospective study was to identify reliable predictive factors for local control of hypopharyngeal cancer (HPC) treated by radiotherapy.
Methods: A cohort of 38 patients with HPC treated by radical radiotherapy at the National Cancer Center Hospital East between 1992 and 1999 were selected as subjects for the present study. Paraffin-embedded pre-therapy biopsy specimens from these patients were used for immunostaining to evaluate the relationships between local tumor control and expression of the following previously reported predictive factors for local recurrence of head and neck cancer treated by radiotherapy: Ki-67, Cyclin D1, CDC25B, VEGF, p53, Bax and Bcl-2. The predictive power of microvessel density (MVD) in biopsy specimens and of clinicopathologic factors (age, gender and clinical tumor-node-metastasis stage) was also statistically analyzed.
Results: Twenty-five patients developed tumor recurrence at the primary site. Univariate analysis indicated better local control of tumors with high microvessel density [MVD >or= median (39 vessels/field)] than with low MVD (< median, P = 0.042). There were no significant associations between local control and expression of Ki-67 (P = 0.467), Bcl-2 (P = 0.127), Bax (P = 0.242 ), p53 (P = 0.262), Cyclin D1 (P = 0.245), CDC25B (P = 0.511) or VEGF (P = 0.496). Clinicopathologic factors were also demonstrated to have no significant influence on local control (age, P = 0.974; gender, P = 0.372; T factor, P = 0.602; N factor, P = 0.530; Stage, P = 0.499).
Conclusion: Microvessel density in biopsy specimens was closely correlated with local control of HPC treated by radiotherapy.