PHARYNGOGRAPHY AFTER HEAD AND NECK IRRADIATION - DIFFERENTIATION OF POSTIRRADIATION EDEMA FROM RECURRENT TUMOR

OBJECTIVE. In patients previously irradiated for head and neck carcino mas, persistent soft-tissue thickening in the larynx and pharynx makes it difficult to distinguish between postirradiation edema and recurre nt epidermoid carcinoma. The goal of this work was to characterize the standard double-contrast pharyngographic appearance after irradiation and to differentiate this appearance from that of recurrent or residu al neoplasms. MATERIALS AND METHODS. The posttreatment pharyngograms i n 43 patients treated with radiotherapy for malignant tumors of the he ad and neck were retrospectively reviewed. The pharynx had been includ ed in the radiation field in each case. We characterized the postthera py appearance and identified radiographic signs that could be used to distinguish normal postirradiation edema from recurrent tumor. RESULTS . Soft-tissue thickening of normal laryngeal and pharyngeal structures and laryngotracheal aspiration were common nonspecific findings on po sttherapy pharyngograms, each occurring in 39 of 43 patients. Epiglott ic enlargement and laryngotracheal aspiration did not correlate with t he presence of residual or recurrent neoplasm. Asymmetric swelling was more common ipsilateral to the original neoplasm and did not necessar ily indicate a malignant tumor. Mucosal irregularity, ulceration, and a demonstrable focal mass were the only significant predictors of recu rrent or residual tumor; at least one of the three findings was presen t in 17 of 19 patients with neoplasm correctly identified by pharyngog raphy. CONCLUSION. Double-contrast pharyngography is a useful means of diagnosing pharyngeal tumors in patients who have had radiation thera py. Radiographic signs of neoplasm (ulcer, mucosal irregularity, and a focal mass) can be used to distinguish recurrent tumor from nonmalign ant changes after irradiation.