Multi-variable models of large International Prostate Symptom Score worsening at the end of therapy in prostate cancer radiotherapy

doi:10.1016/j.radonc.2015.11.036

Radiotherapy and Oncology

Volume 118, Issue 1, January 2016, Pages 92-98

https://doi.org/10.1016/j.radonc.2015.11.036 Get rights and content

Abstract

Purpose/objective

Prospectively assessing clinical/dosimetry factors affecting the acute worsening of urinary functionality after radiotherapy for prostate cancer.

Material/methods

DUE01 population was considered, including patients treated with conventional or moderate hypo-fractionation (2.2–2.7 Gy/fr). Relevant clinical factors were collected, urinary symptoms were self-reported through the International Prostate Symptom Score (IPSS) before and at the end of radiotherapy; while absolute weekly dose–surface histograms (DSH_w) were chosen as dosimetry descriptors.

An IPSS increase of at least 10 and 15 points (ΔIPSS ⩾ 10 and ΔIPSS ⩾ 15) were chosen as endpoints. Patients with baseline IPSS > 20 were excluded. Relevant factors were chosen through a bootstrap-based in silico methodology.

Results

Complete information was available for 380 patients: 77/380 (20%) and 28/380 (7%) with ΔIPSS ⩾ 10 and ΔIPSS ⩾ 15, respectively.

Neoadjuvant hormone was protective (OR = 0.49 and 0.69). DSH_w at 8.5 Gy/week and 12 Gy/week were risk factors, with additional risk for patients who use cardiovascular drugs and anti-hypercholesterolemia drugs.

In the hypo-fractionated subgroup (n = 209) the role of cardiovascular drugs (OR = 2.16) for ΔIPSS ⩾ 10 and anti-hypercholesterolemia drugs (OR = 2.80) for ΔIPSS ⩾ 15, together with DSH_w (10 Gy/week and 12.5 Gy/week, respectively), was confirmed.

Conclusion

Current study shows a dose–surface/volume effect for acute large worsening of urinary functionality; several clinical variables largely impact the risk and especially all the factors related with vascular diseases.

Section snippets

The DUE01 study

DUE01 is a prospective multicenter study aimed at developing predictive models of urinary toxicity and erectile dysfunction after radical high-dose RT for prostate cancer.

Patients were enrolled between April 2010 and December 2014, after the approval of Ethics Committees of all the participating Institutes.

Details of the study may be found elsewhere [11], [12]. In summary, relevant clinical and planning data were prospectively collected for each patient. The continuous clinical parameters

Patient characteristics

The final data set consisted of a total of 539 enrolled patients, 457 had full planning data and, among them, 392 patients had both baseline and end RT IPSS available at the time of analysis.

380/392 (97%) patients had baseline IPSS ⩽ 20, while 209/380 (55%) were treated with HYPO.

Table 1 shows the patient characteristics included in the analysis. No significant difference in the variable proportions between the whole and hypo populations was found (z proportion tests resulted in p > 0.14 for all

Discussion

Despite the recognition that urinary toxicity is a major issue in modern radiotherapy for prostate cancer, few investigations dealt with the development of predictive models based on pre-treatment parameters, including dose–volume information [2], [3], [4], [5], [6], [7]. The main reason for this lack is probably due to the difficulty in following, for a long time, a sufficiently large number of patients whose clinical and dosimetry data need to be individually and prospectively collected with

Conflict of interest statement

None.

Acknowledgments

The study was supported by the Associazione Italiana Ricerca sul Cancro (AIRC-IG13090 and IG16087). Fondazione Italo Monzino is acknowledged for supporting clinical and research activities on prostate cancer. We also thank Cinzia Bianconi and Fabio Badenchini for data management.

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¹: Currently at Radiotherapy, Centro AKTIS Diagnostica e Terapia SpA, Marano di Napoli, Italy.

²: Currently at Nuovo Ospedale, ASL Biella, Biella, Italy.

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Quality of life in prostate cancerMulti-variable models of large International Prostate Symptom Score worsening at the end of therapy in prostate cancer radiotherapy

Abstract

Purpose/objective

Material/methods

Results

Conclusion

Section snippets

The DUE01 study

Patient characteristics

Discussion

Conflict of interest statement

Acknowledgments

Int J Radiat Oncol Biol Phys

Int J Radiat Oncol Biol Phys

Radiother Oncol

Radiother Oncol

Int J Radiat Oncol Biol Phys

Int J Radiat Oncol Biol Phys

Radiother Oncol

Quality of life in prostate cancer
Multi-variable models of large International Prostate Symptom Score worsening at the end of therapy in prostate cancer radiotherapy