The impact of routine CT of the chest on the diagnosis and management of newly diagnosed squamous cell carcinoma of the head and neck.

OBJECTIVE: The purpose of the study was to ascertain how often additional malignant neoplasms are detected on CT scans of the thorax in patients with newly diagnosed squamous cell carcinoma of the head and neck and to determine how often these findings are evident on conventional radiographs of the chest. SUBJECTS AND METHODS: One hundred eighty-nine patients with newly diagnosed squamous cell carcinoma of the head and neck were prospectively examined in a 5-year period. At the time of the initial diagnosis, each patient underwent both chest radiography (posteroanterior and lateral radiographs in 95%, anteroposterior in 5%) and thoracic CT to assess the prevalence of additional primary or metastatic malignant neoplasms of the thorax and upper abdomen. RESULTS: Of the 189 patients studied, 66 showed a total of 73 significant abnormalities on thoracic CT scans of which only 17 abnormalities (23%) were detected on chest radiographs alone. Of these 66 patients, 36 (55%) were found to have one or more primary or metastatic neoplasms. These 36 patients manifested a total of 41 additional primary or secondary malignant neoplasms including 24 cases in which one or more pulmonary nodules were detected, six cases of lymphadenopathy, three hepatic lesions, three bone lesions, two pleural masses, two esophageal masses and one adrenal mass. Of these 41 malignant tumors, 13 (32%) were synchronous primary tumors and 28 were metastases. Only 12 (29%) of the 41 malignant tumors detected by thoracic CT were seen on the chest radiographs. In all patients in which an additional malignant tumor was diagnosed, clinical management was significantly affected, resulting in a modification of the planned surgery or the addition of chemotherapy, radiation therapy, or both. CONCLUSION: A relatively large percentage of patients (19%) with newly diagnosed squamous cell cancer of the head and neck was found to have additional malignant tumors, 32% of which were synchronous primary tumors. The discovery of these additional neoplasms had a major effect on both the therapy and the prognosis of these patients. The combination of a relatively poor detection rate for conventional chest radiography, with only 29% of the malignant tumors detected on CT scans of the chest being seen on chest radiographs, and the high prevalence of disease in this population support the routine inclusion of thoracic CT in these patients.