Oligometastatic cancer in elderly patients: the "blitzkrieg" radiotherapy approach : SBRT in oligometastatic elderly patients

Stereotactic Radiosurgery with Volumetric Modulated Arc Radiotherapy: Final Results of a Multi-arm Phase I Trial (DESTROY-2)

AIMS

To present the final results of a phase I trial on stereotactic radiosurgery (SRS) delivered using volumetric modulated arc therapy (VMAT) in patients with primary or metastatic tumors in different extracranial sites.

MATERIALS AND METHODS

The DESTROY-2 trial, planned as a prospective dose escalation study in oligometastatic (one to five lesions) cancer patients relied on the delivery of a single high dose of radiation utilizing high-precision technology. The primary study endpoint was the definition of the maximum tolerated dose (MTD) of SRS-VMAT. The secondary objectives of the study were the evaluation of safety, efficacy, and long-term outcomes. All patients consecutively observed at our radiotherapy unit matching the inclusion criteria were enrolled. Each enrolled subject was included in a different phase I study arm, depending on the tumor site and the disease stage (lung, liver, bone, other), and sequentially assigned to a particular dose level.

RESULTS

Two hundred twenty seven lesions in 164 consecutive patients (male/female: 97/67, median age: 68 years; range: 29-92) were treated. The main primary tumors were: prostate cancer (60 patients), colorectal cancer (47 patients), and breast cancer (39 patients). The maximum planned dose level was achieved in all study arms, and the MTD was not exceeded. 34 Gy, 32 Gy, 24 Gy, and 24 Gy were established as the single-fraction doses for treating lung, liver, bone, and other extracranial lesions, respectively. The prescribed BED 2Gyα/β:10 to the planning target volume ranged from 26.4 Gy to 149.6 Gy. Twenty-seven patients (16.5%) experienced grade 1-2 and only one grade 3 acute toxicity, which was a pulmonary one. In terms of late toxicity, we registered only 5 toxicity>G2: a G3 gastro-intestinal one, three G3 bone toxicity, and a G3 laryngeal toxicity. The overall response was available for 199 lesions: 107 complete response (53.8%), 50 partial response (25.1%), and 31 stable disease (15.6%), leading to an overall response rate of 94.5%. Progression was registered only in 11 cases (5.5%). The overall response rate in each arm ranged from 88.6% to 96.4%. The overall two-year local control, distant metastasis free survival, disease free survival, and overall survival were 81.7%, 33.0%, 25.4%, and 78.7% respectively.

CONCLUSION

In conclusion, the planned doses of 34 Gy, 32 Gy, 24 Gy, and 24 Gy were successfully administered as single-fractions for the treatment of lung, liver, bone, and other extracranial lesions, respectively, in a prospective SRS dose-escalation trial. No dose-limiting toxicities were registered, and minimal acute and late toxicity were reported. New indications for SRS are currently being studied in oligoprogressive patients receiving targeted drugs or in combination with immunotherapy. The DESTROY-2 trial represents, in our opinion, a credible starting point for future modern radiosurgery trials.

Stereotactic Body Radiotherapy and Immunotherapy for Older Patients with Oligometastases: A Proposed Paradigm by the International Geriatric Radiotherapy Group

The standard of care for metastatic disease is systemic therapy. A unique subset of patients with limited metastatic disease defined as distant involvement of five anatomic sites or less (oligometastases) have a better chance of remission or improved survival and may benefit from local treatments such as surgery or stereotactic body radiotherapy (SBRT). However, to prevent further spread of disease, systemic treatment such as chemotherapy, targeted therapy, and hormonal therapy may be required. Older patients (70 years old or above) or physiologically frail younger patients with multiple co-morbidities may not be able to tolerate the conventional chemotherapy due to its toxicity. In addition, those with a good performance status may not receive optimal chemotherapy due to concern about toxicity. Recently, immunotherapy with checkpoint inhibitors (CPI) has become a promising approach only in the management of program death ligand 1 (PD-L1)-positive tumors. Thus, a treatment method that elicits induction of PD-L1 production by tumor cells may allow all patients with oligometastases to benefit from immunotherapy. In vitro studies have demonstrated that high dose of radiotherapy may induce formation of PD-L1 in various tumors as a defense mechanism against inflammatory T cells. Clinical studies also corroborated those observations. Thus, SBRT, with its high precision to minimize damage to normal organs, may be a potential treatment of choice for older patients with oligometastases due to its synergy with immunotherapy. We propose a protocol combining SBRT to achieve a minimum radiobiologic equivalent dose around 59.5 Gy to all tumor sites if feasible, followed four to six weeks later by CPI for those cancer patients with oligometastases. All patients will be screened with frailty screening questionnaires to identify individuals at high risk for toxicity. The patients will be managed with an interdisciplinary team which includes oncologists, geriatricians, nurses, nutritionists, patient navigators, and social workers to manage all aspects of geriatric patient care. The use of telemedicine by the team may facilitate patient monitoring during treatment and follow-up. Preliminary data on toxicity, local control, survival, and progression-free survival may be obtained and serve as a template for future prospective studies.

A systematic review and meta-analysis on non-metastatic castration resistant prostate cancer: The radiation oncologist's perspective

Prostate cancer is the second most common cause of cancer-related mortality in men. In patients undergoing a failure after radical treatment, one of the therapeutic option is androgen deprivation: despite initial response rates, a progression to a state of castration resistance is observed in most of the patients. In the present article, we conducted a systematic review and meta-analysis of all clinical trials assessing treatment for nmCRPC with next-generation androgen receptor inhibitors. We performed a review and meta-analysis of phase III randomized controlled trials comparing new agents (apalutamide, enzalutamide, darolutamide) with placebo as control arm, in the setting of nmCRPC. Patients treated with next-generation ARIs had a 26% reduction in the risk of death compared with placebo; compared with other ARIs, darolutamide had the lowest rate of grade 3 and 4 AEs and the lowest therapy discontinuation rate due to any grade AEs. This meta-analysis shows that treatment with new ARIs is safe and significantly reduces the risk of death and of metastasis onset in nmCRPC patients. Under way studies on new biomarkers such as genomic classifiers will probably allow the stratification in more specific subsets of disease. New imaging modalities such as PSMA-PET have shown greater sensibility and specificity than conventional imaging in metastases detection. All patients were randomized in a 2:1 fashion, with a total of 2,694 who underwent next-generation ARIs (806 apalutamide, 955 darolutamide, 933 enzalutamide) and 1,423 in the placebo arm.

SBRT for elderly oligometastatic patients as a feasible, safe and effective treatment opportunity

The constantly increasing life expectancy is raising the issue of treating oncological older patients, who were traditionally candidates to best supportive care or palliative treatments. Several literature data support SBRT in the treatment of the oligometastatic patient as a potentially curable therapeutic option. However, data on older patients are lacking. This study presents the outcomes of a cohort of 61 oligometastatic patients over the age of 80 years who received SBRT, that was proposed to all patients with a minimum Karnofsky Performance Status ≥ 70 and a life expectancy of at least 6 months, with up to five oligometastatic lesions. Radiotherapy was delivered in 3-10 fractions with VMAT-IGRT technique. Toxicity was retrospectively collected according to CTCAE v4.0. Data were retrospectively collected and analyzed. Univariate and multivariate analysis were performed for assessing any potential predictive factor for clinical outcomes. A total of 90 oligometastases were treated in 61 patients with median age 82 years (range, 80-90). The most frequent histology was colorectal cancer (27% of cases). Median follow-up was 20 months (range, 2-63). Local control rates at 1- and 2-years were 98.8% and 88.2%, with colorectal histology being associated with worse LC rates (p = 0.014) at univariate analysis. Progression-free survival rates at 1- and 2-years were 48.6% and 30.5%. Oligorecurrent lesions and single oligometastases were associated with better PFS rates (respectively, p = 0.04 and p = 0.011). Overall survival rates were 75% and 60.5%, polymetastatic spread being predictive of worse survival outcomes at multivariate analysis (p = 0.012). No G2 or higher adverse events were recorded. Our study supports the role of SBRT for the treatment of elderly oligometastatic patients, highlighting the possibility to further explore this therapeutic option in the management of older oncological patients.

Percutaneous thermal ablation of lung metastases from thyroid carcinomas. A retrospective multicenter study of 107 nodules. On behalf of the TUTHYREF network

PURPOSE

To determine efficacy and safety of thermal ablation (TA) for the local treatment of lung metastases of thyroid cancer.

METHODS

We retrospectively studied 47 patients from 10 centers treated by TA (radiofrequency, microwaves, and cryoablation) over 10 years. The endpoints were overall survival (OS), local efficacy, complications (CTCAE classification), and factors associated with survival. OS curves after first TA were built using the Kaplan-Meier method and compared with the log-rank test.

RESULTS

A total of 107 lung metastases during 75 sessions were treated by radiofrequency (n = 56), microwaves (n = 9), and cryoablation (n = 10). Median follow-up time after TA was 5.2 years (0.2-13.3). OS was 93% at 2 years (95% confidence interval (CI): 86-94) and 79% at 3 years (95% CI: 66-91). On univariate and multivariate analysis with a Cox model, histology was the only significant factor for OS. OS at 3 years was 94% for follicular, oncocytic, or papillary follicular variant carcinomas, compared to 59% for papillary, medullary, insular or anaplastic carcinomas (P = 0.0001). The local control rate was 98.1% at 1 year and 94.8% at 2, 3, 4, and 5 years. Morbidity was low with no major complications (grade 4 and 5 CTCAE) and no complications in 29 of 75 sessions (38.7%).

CONCLUSIONS

TA is a useful, safe and effective option for local treatment of lung metastases from thyroid carcinoma. Prolonged OS was obtained, especially for lung metastases from follicular, oncocytic, or papillary follicular variant carcinomas. Achieving disease control with TA delays the need for systemic treatment.

Oligometastatic Cancer: Key Concepts and Research Opportunities for 2021 and Beyond

Traditionally, clinicians distinguished three forms of cancer outgrowth [...].

Stereotactic ablative radiotherapy in castration-resistant prostate cancer patients with oligoprogression during androgen receptor-targeted therapy

OBJECTIVES

To report outcomes of stereotactic body radiotherapy (SBRT) in metastatic castration-resistant prostate cancer (mCRPC) patients with oligoprogression (≤ 5 metastases) during first-line treatment with androgen receptor-targeted therapy (ARTT).

PATIENTS AND METHODS

Retrospective multi-institutional analysis of mCRPC patients treated with SBRT to oligoprogressive lesions during ARTT. End-points were time to next-line systemic treatment (NEST), radiological progression-free survival (r-PFS) and overall survival (OS). Toxicity was registered according to Common Terminology Criteria for Adverse Events (CTCAE) v4.0. Survival analysis was performed using the Kaplan-Meier method, univariate and multivariate analysis (MVA) were performed.

RESULTS

Data from 34 patients were analyzed. Median NEST-free survival, r-PFS, and OS were 16.97, 13.47, and 38.3 months, respectively. At MVA, factors associated with worse NEST-free survival and r-PFS were polymetastatic burden at diagnosis of metastatic hormone-sensitive disease (hazard ratio [HR] 3.66, p = 0.009; HR 3.03, p = 0.034), PSA ≤ 7 ng/ml at mCRPC diagnosis (HR 0.23, p = 0.017; HR 0.19, p = 0.006) and PSADT ≤ 3 months at mCRPC diagnosis (HR 3.39, p = 0.026; HR 2.79, p = 0.037). Polymetastatic state at mHSPC diagnosis was associated with a decreased OS (HR 4.68, p = 0.029). No patient developed acute or late grade ≥ 2 toxicity.

CONCLUSION

Our results suggest that SBRT in oligoprogressive mCPRC is safe, effective and seems to prolong the efficacy of the ongoing systemic treatment positively affecting disease progression. Prospective trials are needed.

Systematic review of stereotactic body radiotherapy for nodal metastases

The aim of this analysis was to assess the efficacy of stereotactic body radiotherapy (SBRT) in terms of local control (LC) and progression-free survival (PFS) in patients with lymph node metastases (NMs) from solid tumors. A systematic literature search from the earliest date to July 25th, 2019 was performed following PRISMA guidelines. Papers reporting LC and/or PFS of NMs using SBRT (< 10 fractions) were selected. The clinical outcomes rates were pooled by means of a random or fixed-effect model. Twenty-nine studies were eligible (969 patients: 938 (LC) and 698 (PFS)). LC and PFS results were reported in 28 and 18 papers, respectively. Heterogeneity was observed in terms of patient and treatment characteristics. Pooled 2-year LC reported in 11 studies was 79.3% (95%CI, 72.8%-85.7%) with substantial heterogeneity between studies (Q2 test: p = 0.0083; I2 = 57.9%), while pooled 2-year PFS reported in 8 studies was 35.9% (95%CI, 22.1%-49.7%) with very high heterogeneity between studies (Q2 test: p < 0.0001; I2 = 86.1%). Grade ≥ 3 and Grade 5 toxicity rates were 2.0% and 0.2%, respectively. SBRT of NMs seems to be safe and effective in terms of LC. However, due to the marked heterogeneity of the included series, prospective studies are required.

Whole breast external beam radiotherapy in elderly patients affected by left-sided early breast cancer: a dosimetric comparison between two simple free-breathing techniques

BACKGROUND

Elderly breast cancer patients are frequently affected by significant comorbidities that make sophisticated radiotherapy treatments particularly challenging.

AIMS

We dosimetrically analyzed two different simple free-breathing external beam radiotherapy (EBRT) techniques for the hypofractionated treatment of the left breast in elderly patients with a low compliance, to compare target coverage, and heart and left anterior descending coronary artery (LADCA) sparing.

METHODS

We developed radiation plans for 24 elderly patients using 3D conformal (3DCRT) field-in-field tangential technique and intensity-modulated (IMRT) tangential beam technique. Dose-Volume-Histograms (DVHs) were used to provide a quantitative comparison between plans.

RESULTS

The median breast volume was 645 cm³. IMRT and 3DCRT plans comparison demonstrated no significant differences in terms of organ sparing for the heart. Regarding LADCA, mean dose (10.3 ± 9.5 Gy vs 11.9 ± 9.6 Gy, p = 0.0003), maximum dose (26.1 ± 16.1 Gy vs 29.1 ± 16.1 Gy, p = 0.004) and V_{17 Gy} (21.5% ± 26.9% vs 25.0% ± 27.2%, p = 0.002) significantly decreased using IMRT compared with 3DCRT. IMRT plans showed a better target coverage compared with 3DCRT (0.91 ± 0.05 vs 0.93 ± 0.04, p = 0.05).

DISCUSSION

Comparing the two different EBRT techniques, we demonstrated few, although substantial, dosimetric differences in terms of doses to the organs at risk characterized by a statistically significant dose reduction of LADCA in the IMRT plans.

CONCLUSIONS

Elderly patients with a low compliance to treatment might benefit from 3DCRT with field-in-field tangential arrangement or from a simple IMRT approach. IMRT should be preferred.

Challenges and advances in cervix cancer treatment in elder women

With population ageing, cancer treatments in elder patients is becoming a true public health care issue. There is an authentic dilemma between patient's frailty, residual life expectancy and the toll that take anticancer treatments. Since elder patients are almost always excluded from clinical trials, it is hard to get robust scientific data on the tolerability of oncologic treatments and to set in place recommendations. Cervix cancer is traditionally diagnosed in younger women but it has a 2nd incidence peak between 60 and 70 years old. Cervix cancer in elder patients is a subject to many questions in terms of screening and is a therapeutic challenge. This article reviews literature data on these different aspects, from screening to surgery, from radiotherapy to brachytherapy, from chemotherapy to supportive care, from immunotherapy to geriatric assessment. We tried to show how modern therapeutic innovations may benefit elder patients. Expected benefits in terms of efficacy and toxicity may overcome the long-lasting tendency to undertreatment in elder patients and improve their quality of life after cancer treatment. In 2020, there seems to be less and less reasons justifying that elder women with cervix cancer may not receive the appropriate treatment.

Physician And Patient Barriers To Radiotherapy Service Access: Treatment Referral Implications

Radiotherapy is one of the mainstays of cancer treatment, and about 60% of cancer patients receive this type of treatment during their course of treatment. An evident gap between optimal and actual radiotherapy utilization proportions has recently been reported, which has been ascribed to lack of referral to radiation oncology. There are many factors influencing the radiotherapy referral, including patient anxiety about toxicity, wrong perception of efficacy and side effects by physicians and patients, insufficient knowledge of referral process. These factors, defined as barriers can be categorized in health system barriers, physician and patient barriers. In the present brief narrative review, we discussed barriers to radiotherapy referral focusing on physician and patient barriers.