High weekly integral dose and larger fraction size increase risk of fatigue and worsening of functional outcomes following radiotherapy for localized prostate cancer

Whole-body integral dose and post-radiotherapy lymphocytopaenia in solid tumours

Objective

Since modern radiotherapy techniques such as intensity-modulated radiotherapy (IMRT) pivot on a strategy of dose redistribution, it may increase integral dose and consequently worsening of lymphocytopaenia. In this study, our objective was twofold: first to validate the correlation between integral body dose and post-treatment lymphocytopaenia in a cohort of patients treated with curative-intent radiotherapy and second to validate its prognostic impact.

Methods and analysis

Patients treated with curative intent radiotherapy with complete blood counts were included in the study. Data on the following variables were collected: treatment site, prescribed dose, use of concurrent chemotherapy, mean body dose, mean body volume, treatment technique and disease-free survival.

Results

A total of 116 patients were included for analysis. There was a significant decline in lymphocyte counts after radiotherapy (2.2×109/L vs 0.8×109/L; p<0.001). Multivariate linear regression analysis of post-treatment lymphocytopaenia revealed a significant correlation with pretreatment lymphocyte counts, integral body dose, use of IMRT and use of concurrent radiosensitising chemotherapy. Univariate survival analysis was performed in 37 patients with squamous cell carcinoma of the head and neck. In the Cox proportional hazards model, post-treatment lymphocyte count was statistically significant as a continuous variable (Hazard Ratio=0.998, p=0.01) and as a dichotomous variable.

Conclusion

The negative correlation between integral body dose and post-treatment lymphocytopaenia was validated, and post-treatment lymphocytopaenia is an adverse prognostic factor in patients with head and neck cancer treated with curative-intent radiotherapy.

Photon vs proton hypofractionation in prostate cancer: A systematic review and meta-analysis

BACKGROUND

High-level evidence on hypofractionated proton therapy (PT) for localized and locally advanced prostate cancer (PCa) patients is currently missing. The aim of this study is to provide a systematic literature review to compare the toxicity and effectiveness of curative radiotherapy with photon therapy (XRT) or PT in PCa.

METHODS

PubMed, Embase, and the Cochrane Library databases were systematically searched up to April 2022. Men with a diagnosis of PCa who underwent curative hypofractionated RT treatment (PT or XRT) were included. Risk of grade (G) ≥ 2 acute and late genitourinary (GU) OR gastrointestinal (GI) toxicity were the primary outcomes of interest. Secondary outcomes were five-year biochemical relapse-free survival (b-RFS), clinical relapse-free, distant metastasis-free, and prostate cancer-specific survival. Heterogeneity between study-specific estimates was assessed using Chi-square statistics and measured with the I2 index (heterogeneity measure across studies).

RESULTS

A total of 230 studies matched inclusion criteria and, due to overlapped populations, 160 were included in the present analysis. Significant lower rates of G ≥ 2 acute GI incidence (2 % vs 7 %) and improved 5-year biochemical relapse-free survival (95 % vs 91 %) were observed in the PT arm compared to XRT. PT benefits in 5-year biochemical relapse-free survival were maintained for the moderate hypofractionated arm (p-value 0.0122) and among patients in intermediate and low-risk classes (p-values < 0.0001 and 0.0368, respectively). No statistically relevant differences were found for the other considered outcomes.

CONCLUSION

The present study supports that PT is safe and effective for localized PCa treatment, however, more data from RCTs are needed to draw solid evidence in this setting and further effort must be made to identify the patient subgroups that could benefit the most from PT.

Patient-reported persistent symptoms after radiotherapy and association with quality of life for prostate cancer survivors

PURPOSE

To evaluate the persistence of symptoms after radiotherapy (RT) for localised prostate cancer (PCa) and the association with quality of life (QOL).

MATERIALS AND METHODS

Prospective patient-reported outcome (PRO) from a multi-institutional study on PCa treated with radical RT (2010-2014) was analysed. Data was collected at baseline (BL) and follow-ups (FUPs) up to 5 years. Patients with BL and ≥3 late FUPs (≥6 months) were analysed. PRO was scored by means of the IPSS and ICIQ-SF (urinary), LENT-SOMA (gastrointestinal [GI]), and EORTC-C30 (pain, insomnia, fatigue, and QOL) questionnaires. Symptoms were defined 'persistent' if the median score over FUPs was ≥3 (urinary) or ≥2 (GI, pain, insomnia, and fatigue), and worse than BL. Different thresholds were chosen to have enough events for each symptom. QOL was linearly transformed on a continuous scale (0-100). Linear-mixed models were used to identify significant differences between groups with and without persistent symptoms including age, smoking status, previous abdominal surgery, and diabetes as confounders. Mean QOL differences between groups were evaluated longitudinally over FUPs.

RESULTS

The analysis included 293 patients. Persistent urinary symptoms ranged from 2% (straining) to 12% (weak stream, and nocturia). Gastrointestinal symptoms ranged from 7% (rectal pain, and incontinence) to 30% (urgency). Proportions of pain, insomnia, and fatigue were 6, 13, and 18%. Significant QOL differences of small-to-medium clinical relevance were found for urinary incontinence, frequency, urgency, and nocturia. Among GI symptoms, rectal pain and incontinence showed small-to-medium differences. Fatigue was associated with the largest differences.

CONCLUSIONS

The analysis showed that symptoms after RT for PCa occur with different persistence and their association with QOL varies in magnitude. A number of persistent urinary and GI symptoms showed differences in a comparable range. Urinary incontinence and frequency, rectal pain, and faecal incontinence more often had significant associations. Fatigue was also prevalent and associated with largely deteriorated QOL.