Prognostic factors for loco/regional control and metastasis and the impact on survival

Abstract

For the identification of predictive factors for local (head and neck) control and metastases and impact on survival in squamous cell cancer of the head and neck, we have used data from over 2000 patients from the Patterns of Care Study (PCS) and the Radiation Therapy Oncology Group (RTOG) studies. Complete local response (C.R.) is significantly related to T stage, N stage, general performance status (Karnofsky), and site of primary tumor. There is a strong association between T and N stage. T1N0 tumors showed a C.R. of 99%, whereas, TIN' had a C.R. of 57%. T4N0 showed a C.R. of 75%, but this went down to 31% in the T4N3 lesions. Glottic tumors showed a C.R. of 96% versus the other sites, which ranged from 81% for the nasopharynx to 59% for the hypopharynx. Patients with a performance status (KPS) of less than 90% showed a C.R. of 60% versus 88% for AKPS 90% or higher. Absence of local recurrence after C.R. is significantly related to T stage, N stage, and the site of primary tumor (glottis versus the rest). The appearance of distant metastases is significantly related only to N stage and primary site. This relationship persists in control of loco/regional tumors. In Stages III & IV in non-glottic head and neck cancer, metastases as the cause of death play an increasingly important role. This can be as high as 30%. The appearance of new malignant tumors and death unrelated to cancer, that is, death related to lifestyle, assumes an important role in patients with advanced head and neck cancer. The number of advanced glottic larynx was too small to examine this question. The use of a surgical procedure in carcinomas of the anterior tongue and floor of the mouth was associated with a smaller percentage of infield recurrences at 2 years, than when radiation therapy alone was used (27% versus 88% p < .01). The same observation was noted at 3 years in the glottic and supraglottic Stage III & IV tumors ( p < .01).