Correlation between dosimetric parameters and late rectal and urinary toxicities in patients treated with high-dose-rate brachytherapy used as monotherapy for prostate cancer.

Abstract

PURPOSE:

To evaluate the correlation between dosimetric parameters and late rectal and urinary toxicities in high-dose-rate brachytherapy (HDR-BT) used as monotherapy for prostate cancer.

METHODS AND MATERIALS:

The data of 83 patients treated with HDR-BT alone for prostate cancer from 2001 through 2005 at Osaka University Hospital were analyzed. Median follow-up time was 36 months (range, 18-70). The total prescribed dose was 54 Gy in nine fractions over 5 days. Correlation between dosimetric parameters and late toxicities was examined.

RESULTS:

The means of V30, V40, V50, V60, V70, D1cc, D2cc, D5cc, and D10cc of the rectum were significantly higher in 18 patients who presented with late rectal toxicity (Grades 1-3 rectal bleeding) than in the other 65 patients who did not. A significant difference was observed for D1cc-10cc but not for D5-90. The statistically most significant difference was observed for V40 and D5cc. Late rectal toxicity rate was significantly higher for patients with rectal V40 >or= 8 cc than those with the rectal V40 < 8 cc (42% vs. 8%; p < 0.001), as well as for patients with rectal D5cc >or= 27 Gy compared with those with rectal D5cc < 27 Gy (50% vs. 11%; p < 0.001). Dosimetric parameters of the urethra of 15 patients with late urinary toxicity were not significantly different from the 68 patients without toxicity.

CONCLUSION:

Rectal V40 < 8 cc and D5cc < 27 Gy may be dose-volume constraints in HDR-BT used as monotherapy for prostate cancer.

• Authors: Koji Konishi, Yasuo Yoshioka, Fumiaki Isohashi, Iori Sumida, Yoshifumi Kawaguchi, Tadayuki Kotsuma, Kana Adachi, Masahiro Morimoto, Shoichi Fukuda, Takehiro Inoue
• Journal: International journal of radiation oncology, biology, physics (Int J Radiat Oncol Biol Phys) Vol. 75 Issue 4 Pg. 1003-7 (Nov 15 2009) ISSN: 1879-355X [Electronic] United States
• PMID: 19345517 (Publication Type: Evaluation Study, Journal Article)

Chemical References

• Androgen Antagonists
• Prostate-Specific Antigen

Topics

• Adenocarcinoma (pathology, radiotherapy)
• Aged
• Androgen Antagonists
• Brachytherapy (adverse effects, methods)
• Follow-Up Studies
• Gastrointestinal Hemorrhage (etiology)
• Hematuria (etiology)
• Humans
• Male
• Middle Aged
• Neoplasm Staging
• Prostate-Specific Antigen (blood)
• Prostatic Neoplasms (blood, pathology, radiotherapy)
• Radiation Injuries (complications)
• Radiotherapy Dosage
• Radiotherapy Planning, Computer-Assisted
• Rectum (radiation effects)
• Tumor Burden (radiation effects)
• Urethra (radiation effects)
• Urination Disorders (etiology)