Retrospective analysis of late rectal bleeding in prostate cancer patients treated with intensity modulated radiotherapy (IMRT)

AbstractAimTo quantify the relationship between the planning target volume (PTV) dose homogeneity and organs at risk (OARs) sparing in correlation with anatomical parameters in prostate intensity-modulated radiotherapy (IMRT).Materials and methodsNine IMRT plans with various target dose constraints’ priorities were created for 15 prostate cancer patients. Selected PTV and OARs parameters were calculated for the patients. A trade-off was assessed between homogeneity index (HI) and OAR sparing. Several anatomical parameters were evaluated to investigate their effects on the OAR sparing and HI.ResultsInverse exponential relationships were found between the OAR sparing and HI (average R 2 of 0·983 and 0·994 for bladder and rectum, respectively). Decreasing the priority led to more OARs sparing (normal tissue complication probability reduction: 97·6 and 74·5%; mean dose reduction: 16·3 and 11·3% for bladder and rectum, respectively) and worsening of the HI (0·095–0·322) but with no significant effect on tumour control probability. Furthermore, OARs volumes, distances between OARs and PTV and their joint volumes had stronger correlations with OARs’ mean doses.ConclusionEnforcement of target dose constraints was more effective on the improvement of HIs for the patients with initial high HI values at low dose constraints’ priorities. Reducing the priority had more effects on the OARs sparing compared to HI, especially for the patients with high OAR doses in high priority plans. This can be attributed to smaller distances or greater joint volumes between the OARs and PTV.

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Serum testosterone level after intensity-modulated radiotherapy in low-risk prostate cancer patients: does testicular dose correlate with testosterone level?

Journal of Radiation Oncology ◽

10.1007/s13566-012-0007-1 ◽

2012 ◽

Vol 1 (2) ◽

pp. 173-177 ◽

Cited By ~ 2

Author(s):

Hiromichi Ishiyama ◽

Bin S. Teh ◽

Arnold C. Paulino ◽

Subashini Yogeswaren ◽

Wei-yuan Mai ◽

...

Keyword(s):

Prostate Cancer ◽

Cancer Patients ◽

Testosterone Level ◽

Intensity Modulated Radiotherapy ◽

Serum Testosterone ◽

Low Risk ◽

Serum Testosterone Level ◽

Intensity Modulated ◽

Risk Prostate Cancer ◽

Low Risk Prostate Cancer

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Impact on Late Toxicity of using Transabdominal Ultrasound for Prostate Cancer Patients Treated with Intensity Modulated Radiotherapy

Technology in Cancer Research & Treatment ◽

10.1177/153303460500400115 ◽

2005 ◽

Vol 4 (1) ◽

pp. 115-120 ◽

Cited By ~ 4

Author(s):

Ashesh B. Jani ◽

John Gratzle ◽

Emil Muresan ◽

Mary K. Martel

Keyword(s):

Prostate Cancer ◽

Cancer Patients ◽

External Beam Radiotherapy ◽

Intensity Modulated Radiotherapy ◽

Late Toxicity ◽

Institutional Setting ◽

Regression Analyses ◽

Intensity Modulated ◽

Gu Toxicity ◽

Gi Toxicity

An analysis of the effects of using the B-mode ultrasound Acquisition and Targeting (BAT) system for positioning of prostate cancer patients receiving external beam radiotherapy (EBRT) on late gastrointestinal (GI) and genitourinary (GU) toxicity is provided. The records of 49 consecutive patients treated using the BAT were reviewed; additionally, a comparison (No-BAT) group treated in a similar manner was identified, consisting of 49 patients treated immediately prior to this BAT group. There were no other fundamental differences between the two groups. The daily BAT movements were charted and late toxicity was scored for all patients using established toxicity scales. The results demonstrated similar GU toxicity rates between the two groups, but slightly lower rates of GI toxicity in the BAT group vs. the No-BAT group. However, regression analyses revealed that no factors, including BAT use, were significantly correlated with late GI or GU toxicity. Further efforts, perhaps better undertaken in a multi-institutional setting, are needed to determine whether BAT use can significantly reduce late GI toxicity.

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