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Subsequent Cancer Risk in Prostate Cancer

Lancet Oncol; ePub 2019 Mar 15; Mohamad, et al

Patients with localized prostate cancer and treated with carbon ion radiotherapy may have a lower risk of subsequent primary cancers than those treated with photon radiotherapy, a new study suggests. Eligible patients in the retrospective cohort study had histologically confirmed localized prostate cancer and a minimum follow-up of at least 3 months. Researchers found:

  • Of 1,580 patients who received carbon radiotherapy for prostate cancer, 1,455 (92%) patients met eligibility criteria.
  • Of 38,584 patients identified with prostate cancer, 1,983 (5%) patients treated with photon radiotherapy and 5,948 (15%) treated with surgery were included.
  • 234 subsequent primary cancers were diagnosed in the carbon ion radiotherapy cohort.
  • In propensity score-weighted analyses, carbon ion radiotherapy was associated with a lower risk of subsequent primary cancers vs photon radiotherapy (HR 0.81) or surgery (HR 0.80), whereas photon radiotherapy was associated with a higher risk of subsequent primary cancers vs surgery (HR 1.18).


Mohamad O, Tabuchi T, Nitta Y, et al. Risk of subsequent primary cancers after carbon ion radiotherapy, or surgery for localised prostate cancer: A propensity score-weighted, retrospective, cohort study. [Published online ahead of print March 15, 2019]. Lancet Oncol. doi:10.1016/S1470-2045(18)30931-8.