Purpose: The relationship between the volumetric and histologic responses of metastatic cervical nodes to radiotherapy or chemotherapy in the oral and maxillofacial region is unclear. In this study, we evaluated the correlation between the initial volume and regression rate of metastatic nodes with their histologic response to preoperative radiotherapy or radiochemotherapy.
Patients and methods: The volume of 54 metastatic nodes in 32 patients with squamous cell carcinoma in the oral and maxillofacial region was measured by ultrasonography before and after preoperative therapy, and the rate of the volume change was calculated. All surgically removed nodes were histologically classified as poor, good, or complete response according to their histologic features.
Results: There was no significant difference in initial volume among the 3 response groups. Good and complete response nodes showed a significant increase in regression rate compared with poor response nodes. All 11 nodes showing no regression were poor response nodes, and 7 with a regression rate of more than 90% were good or complete response nodes. The remaining 36 nodes (regression rate, 0% to 90%) represented all 3 types of histologic response. Of these, 7 of 9 complete response nodes were found in 5 patients who received combination chemotherapy consisting of 5-fluorouracil, leucovorin, and cisplatin.
Conclusions: The initial nodal volume before therapy is not a good indicator for the response to radiotherapy and/or chemotherapy. A regression rate of more than 90% may be a useful predictor of the effectiveness of preoperative treatments, but it was difficult to define the cutoff values in regression rates for differentiating types of histologic response.