Clinical outcomes of helical tomotherapy for super-elderly patients with localized and locally advanced prostate cancer: comparison with patients under 80 years of age

Abstract

We investigated the clinical outcomes of helical tomotherapy in 23 patients aged ≥80 years with localized and locally advanced prostate cancer and compared the results with data from 171 patients under 80 years. All patients received helical tomotherapy in our hospital between September 2009 and October 2012. The median follow-up periods were 35 months in the aged group and 34 months in the younger group. The median prescribed dose in helical tomotherapy was 78 Gy in 39 fractions (range, 72-78 Gy). The 3-year overall survival and biochemical relapse-free rates were 92% and 96% in the aged group and 99.4% and 97.3% in the younger group, respectively. There was no significant difference between the two groups in the biochemical relapse-free rates. The 3-year cumulative incidences of late Grade 2 or higher rectal toxicity and urinary toxicity were 13% and 4.8% in the aged group and 7.0% and 1.2% in the younger group, respectively. There was no significant difference between the aged group and the younger group in the cumulative incidence rates of rectal toxicity or urinary toxicity. No patients exhibited Grade 4 or higher toxicity, and all patients improved with conservative therapy. Helical tomotherapy in super-elderly patients with localized and locally advanced prostate cancer had good biochemical control rates without severe late toxicity. Definitive helical tomotherapy may be the treatment of choice for patients with localized and locally advanced prostate cancer, even in those older than 80 years of age.

Keywords: helical tomotherapy (TOMO); intensity-modulated radiotherapy (IMRT); prostate cancer; super-elderly patients.

Fig. 1.

Overall survival rates and biochemical relapse-free rates after TOMO. Solid lines show the overall survival rates, and dashed lines indicate the biochemical relapse-free rates after TOMO. Blue lines depict the rates for patients 80 years and older, and green lines illustrate rates for patients younger than 80 years old. There was a significant difference in the overall survival rates.

Fig. 2.

Cumulative occurrence rates of late Grade 2 or higher rectal and urinary toxicities after TOMO. The solid lines show the cumulative occurrence rates of rectal toxicity, and dashed lines indicate the cumulative occurrence rates of urinary toxicity. Blue lines illustrate rates for patients 80 years and older, and green lines show the rates for patients younger than 80 years old. There was no significant difference in the cumulative incidence rate or rectal or urinary toxicity.