Interim analysis of a Phase III trial showed that Navidea Biopharmaceuticals' imaging agent Lymphoseek was able to accurately detect cancerous lymph nodes in 38 of 39 patients with head and neck cancer. Use of the agent allowed for the removal of fewer lymph nodes -- an average of four per patient, compared with 38 under standard care. In light of the findings, a safety monitoring committee has advised that the trial be halted early, the company said. Navidea is planning to seek approval of the expanded use of the agent later this year. Lymphoseek was approved last month for lymphatic mapping in people who have breast cancer or melanoma.