The effect of chemotherapy in head and neck cancer patients who had local rests or local recurrence after radiation therapy or with distant metastasis: The effect of chemotherapy was investigated in 54 patients with head and neck cancer who had local residual disease or recurrences after radiation therapy or with distant metastasis. The objective response was found only in ten (% 18.5) patients, with complete remission only in 6 (% 11.7) patients. Five patients (% 19.2) with residual disease and one patient (% 14.2) with distant metastasis had complete response. There was no complete response on patients with local recurrence. As examined for anatomic sites, five patients with nasopharyngeal cancer and one patient with tonsil cancer had complete response. Two patients with laryngeal cancer only had partial response, there was no response in patients with other anatomic locations. The interesting point was the tumors were all undifferentiated in all patients who had complete response. We conclude that chemotherapy is ineffective in head and neck cancer patients who had local rests or local recurrences after radiation therapy or with distant metastasis, but there is little effect in those who have undifferentiated histology.