Role of chest CT scanning in the management of patients presenting with head and neck cancer.

BACKGROUND

The detection of synchronous tumors, whether they be second primaries or distant metastases, in patients with head and neck carcinoma drastically affects prognosis and may alter management. Computerized tomographic (CT) scanning of the chest is an effective screening investigation in this group of patients, both in the detection of synchronous second primary tumors, the incidence of which in this study is 15%, and for accurate staging of metastatic pulmonary disease. The incidence of synchronous tumors in patients who are initially seen with head and neck squamous cell carcinoma (HNSCC) has been reported in large retrospective studies as being between 1% and 3%. These may be either second primary tumors or metastases, and the lung is the commonest site for both.

METHODS

Eighty-one head and neck cancer patients (67 primary and 14 secondary referrals) treated at the Royal Liverpool University Hospital between 1994 and 1996 underwent CT scanning of the chest with ultrasound of the liver as part of their routine staging. The results were compared with standard chest x-rays also performed in each patient.

RESULTS

Fourteen patients had pulmonary tumors detected on the chest CT scan. In 67 patients, the scan was negative. Patients with negative scans tended not to have neck node metastases (64%), whereas patients with positive scans were much more likely to have neck node metastases with negative necks present in only 36% of patients. Where multivariate analysis was carried out, there was a correlation between neck node metastases and positive CT scans of the chest (estimate = 0.5755, standard error = 0.3066, chi2(1) = 6.73, p .047). The sensitivity of chest x-ray compared with CT scan was only 21 % and the specificity 99%. The positive predictive value of a chest x-ray was 75% and the negative predictive value 86%. Intra-abdominal lesions were detected in two patients, one in the liver and one in the adrenal gland. In the latter patient, this was an isolated lesion, but in the former, the chest scan was also positive. In the 67 patients, who were initially seen at the Royal Liverpool Hospital (primary referrals), the incidence of synchronous tumors was 15%.

CONCLUSIONS

Synchronous tumors, whether they be second primary tumors or distant metastases, are more common in patients initially seen with head and neck cancer than is realized, their incidence being significantly higher in those patients with cervical metastases. Computerized tomographic scanning of the chest is a more effective screening investigation than chest x-ray in this group of patients and is now used routinely in our department prior to undertaking major head and neck surgery.