T1 T2 GLOTTIC CANCER MANAGED BY EXTERNAL-BEAM RADIOTHERAPY - THE INFLUENCE OF PRETREATMENT HEMOGLOBIN ON LOCAL-CONTROL/

Purpose: Pretreatment hemoglobin (Hb) level has been reported to be an important prognostic factor for local control and survival in various malignancies. However, in many settings, the adverse effect of a low Hb may be related to more advanced disease. The purpose of this analys is was to assess the influence of pretreatment Hb on local control in a large series of patients with a localized cancer (T1/T2 glottic canc er, AJCC 1992) treated in a standard fashion. Materials and Methods: B etween January 1981 and December 1989, 735 patients (median age 63; 65 7 males, 78 females) with T1/T2 glottic cancer were treated with radia tion therapy (RT). The standard RT prescription was 50 Gy in 20 fracti ons over 4 weeks (97% of patients). Factors studied for prognostic imp ortance for local failure included pretreatment Hb, age, sex, T catego ry, anterior commissure involvement, subglottic extension, and tumor b ulk (presence of visible tumor vs. subclinical disease). Results: With a median follow up of 6.8 years (range 0.2-14.3), 131 patients have l ocally relapsed for an actuarial 5-year relapse-free rate of 81.7%. Th e 5-year actuarial survival was 75.8%. The mean pretreatment hemoglobi n level was 14.8 g/dl and was similar in all prognostic categories. On multivariate analysis, using the Cox proportional hazards model, pret reatment Hb predicted for local failure after RT. The hazard ratio (HR ) for relapse was calculated for various Hb levels. For example, the H R for a Hb of 12 g/dl vs, a Hb of 15 g/dl was 1.8 (95% confidence inte rval 1.2-2.5). Previously established factors, including gender, T cat egory, subglottic extension, as well as tumor bulk, were also prognost ically important for local control. Conclusions: This analysis, in a l arge number of similarly treated patients, indicates that pretreatment Hb is an independent prognostic factor for local control in patients with T1/T2 carcinoma of the glottis treated with RT. The underlying bi ology of this observation needs to be explored, and using this informa tion, it may be possible to develop strategies to improve treatment ou tcome. (C) 1998 Elsevier Science Inc.