Acute side effects after definitive stereotactic body radiation therapy (SBRT) for patients with clinically localized or locally advanced prostate cancer: a single institution prospective study

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.

Predictors of Early Hospice or Death in Patients With Inoperable Lung Cancer Treated With Curative Intent

INTRODUCTION

Treatment for inoperable stage II to III non-small cell lung cancer (NSCLC) involves chemo-radiotherapy (CRT). However, some patients transition to hospice or die early during their treatment course. We present a model to prognosticate early poor outcomes in NSCLC patients treated with curative-intent CRT.

METHODS AND MATERIALS

Across a statewide consortium, data was prospectively collected on stage II to III NSCLC patients who received CRT between 2012 and 2019. Early poor outcomes included hospice enrollment or death within 3 months of completing CRT. Logistic regression models were used to assess predictors in prognostic models. LASSO regression with multiple imputation were used to build a final multivariate model, accounting for missing covariates.

RESULTS

Of the 2267 included patients, 128 experienced early poor outcomes. Mean age was 71 years and 59% received concurrent chemotherapy. The best predictive model, created parsimoniously from statistically significant univariate predictors, included age, ECOG, planning target volume (PTV), mean heart dose, pretreatment lack of energy, and cough. The estimated area under the ROC curve for this multivariable model was 0.71, with a negative predictive value of 95%, specificity of 97%, positive predictive value of 23%, and sensitivity of 16% at a predicted risk threshold of 20%.

CONCLUSIONS

This multivariate model identified a combination of clinical variables and patient reported factors that may identify individuals with inoperable NSCLC undergoing curative intent chemo-radiotherapy who are at higher risk for early poor outcomes.

Second Chance for Cure: Stereotactic Ablative Radiotherapy in Oligometastatic Disease

PURPOSE

Local ablative therapy, such as radiotherapy or surgery, plays a key role in treatment of patients with oligometastatic disease. Stereotactic ablative body radiotherapy (SABR) comes to the fore as a safe and effective treatment for patients with a limited number of metastases, even those located in hard-to-reach body sites. Many researchers have suggested that metastatsis-directed therapy could improve long-term progression-free survival (PFS) and overall survival (OS) in patients with oligometastases.

PATIENTS AND METHODS

This was a retrospective, single-arm, observational study conducted between July 2015 and February 2022. In our institute, 60 patients with controlled primary tumors and one to five metastases were treated with SABR. Prescribed radiation doses ranged from 12 to 60 Gy administered in one to seven fractions. We aimed to determine whether metastatic-directed therapy using SABR for all oligometastases affects OS and PFS and whether the primary tumor or metastatic site influences OS/PFS.

RESULTS

The most common primary malignancy types were prostate (n = 14), colorectal (n = 10), lung (n = 7), and breast cancers (n = 6). The median follow-up was 30 months, ranging from 9 to 79. The 1-, 3-, and 5-year PFS and OS rates were 54.9%, 37.0%, and 37.0% and 98.3%, 84.4%, and 73.8%, respectively, and the median time to first progression was 15 (range, 2-32) months. Twenty-four (40%) patients had no recurrence. In our analysis, primary tumor site was not an independent prognostic factor. The metastatic site may influence on patient outcome in cases of localized bone and liver metastases.

CONCLUSION

In our retrospective analysis, SABR was associated with favorable levels of PFS and OS in patients with oligometastases. The limitations of our study were lacking high-level evidence, and randomized studies to compare SABR and palliative standard of care are mandatory.