Oligometastases revisited

Impact of Progressive Site-Directed Therapy in Oligometastatic Castration-Resistant Prostate Cancer on Subsequent Treatment Response

Simple Summary

Local treatment for oligometastatic hormone-naive prostate cancer has been shown to be effective in phase II trials. As for the efficacy of targeted therapy for oligometastatic castration-resistant prostate cancer, the results of the phase trial are not yet available, but the number of reports showing efficacy by retrospective analysis is increasing. Progressive site-directed therapy has been shown to delay the next intervention and prolong progression-free survival, but its impact on subsequent treatment efficacy and contribution to overall survival has not been reported. The purpose of this retrospective study is to evaluate the impact of progressive site-directed therapy for oligometastatic castration-resistant prostate cancer on the subsequent treatment outcomes. We found that progressive site-directed therapy was associated with better response to subsequent androgen receptor axis-targeted drugs and better overall survival. Progressive site-directed therapy for oligometastatic castration-resistant prostate cancer may improve subsequent oncological outcomes.

Abstract

The purpose of this study was to evaluate the impact of progressive site-directed therapy (PSDT) for oligometastatic castration-resistant prostate cancer (OM-CRPC) on the efficacy of subsequent androgen receptor axis-targeted (ARAT) drugs, and to demonstrate the possibility of prolonging overall survival (OS). We performed a retrospective analysis of 15 OM-CRPC patients who underwent PSDT and subsequently received first-line ARAT drugs (PSDT group) and 13 OM-CRPC patients who were treated with first-line ARAT drugs without PSDT (non-PSDT group). PSDT was performed with the intention of treating all progressing sites detected by whole-body diffusion-weighted MRI with radiotherapy. Thirteen patients (86.7%) treated with PSDT had a decrease in PSA levels, which was at least 50% in 10 (66.7%) patients. The median PSA progression-free survival (PFS) for PSDT was 7.4 months. The median PSA-PFS for ARAT was 27.2 months in patients in the PSDT group and 11.7 months in the non-PSDT group, with a significant difference between the two groups (hazard ratio [HR], 0.28; p = 0.010). The median OS was not reached in the PSDT group and was significantly longer than 44.5 months in the non-PSDT group (HR, 0.11; p = 0.014). In OM-CRPC, PSDT may improve the efficacy of subsequent ARAT and OS.

Local consolidative therapy for synchronous oligometastatic non‐small cell lung cancer treated with first‐line pembrolizumab: A retrospective observational study

Background

Local consolidative therapy (LCT) has emerged as a treatment option in patients with oligometastatic non‐small cell lung cancer (NSCLC) undergoing chemotherapy or targeted therapy. However, the current literature lacks evidence as to whether LCT improves survival in NSCLC patients receiving immunotherapy. Our study aimed to assess whether LCT combined with pembrolizumab ± chemotherapy could improve the survival of patients with synchronous oligometastatic NSCLC.

Methods

Patients with NSCLC, without EGFR or ALK genetic aberrations, who were treated with first‐line pembrolizumab ± chemotherapy, were included in the study. Survival analysis of the LCT and non‐LCT groups was compared.

Results

A total of 231 patients were included in the study. The median follow‐up time was 15.24 months. Median progression‐free survival (PFS) and overall survival (OS) of the entire cohort were 12.00 and 23.43 months, respectively. Of the 231 patients included, 76 patients received LCT combined with pembrolizumab ± chemotherapy (LCT group) while 155 patients received pembrolizumab ± chemotherapy alone (non‐LCT group). Of note, the PFS of the LCT and non‐LCT groups was 13.97 and 10.08 months (p = 0.016), respectively. The OS were 30.67 and 21.97 months (p = 0.011), respectively. The PFS and OS were significantly improved with LCT for patients with brain or lung metastases but not bone metastases. No significant increase in treatment‐related toxicity was observed in the LCT group.

Conclusions

The present study shows that LCT to metastatic sites is an option for consideration in patients with synchronous oligometastatic NSCLC during first‐line pembrolizumab treatment, with significantly improved PFS and OS compared with systemic treatment alone.

Cost-effectiveness of treatment strategies for spinal metastases

PURPOSE

We analyze the cost-effectiveness of standard palliative external beam radiation (EBRT, 8 Gy in 1 fraction), stereotactic body radiation therapy (SBRT, 24 Gy in 2 fractions), and radiofrequency ablation (RFA) for painful spinal metastases. Single-fraction SBRT (delivering 24 Gy) is also assessed.

METHODS AND MATERIALS

A Markov state transition model was constructed. Key model parameters were derived from prospective clinical trial data. Strategies were compared using the incremental cost-effectiveness ratio (ICER), with effectiveness in quality-adjusted life years (QALYs) and a willingness-to-pay (WTP) threshold of $100,000 per QALY gained. Costs included both hospital and professional costs using 2020 Medicare reimbursement.

RESULTS

The base case demonstrated that 2-fraction SBRT was not cost-effective compared to single-fraction EBRT, with an ICER of $194,145/QALY gained. RFA was a dominated treatment strategy (more costly and less effective) in this model. Probabilistic sensitivity analysis demonstrated that EBRT was favored in 66% of model iterations. If median survival were improved after SBRT, two-fraction SBRT became cost-effective, with ICER of $80,394, $57,062, and $47,038 for 3, 6, and 9-month improvements in survival. Because two-fraction SBRT data reported 18% of patients with indeterminant pain response at 3 months, and two-fraction SBRT is infrequently used in clinical practice, single-fraction SBRT data was also assessed. Single-fraction SBRT delivering 24 Gy was cost-effective compared to single-fraction EBRT, with an ICER of $92,833/QALY gained.

CONCLUSIONS

For appropriately chosen patients, single-fraction SBRT is more cost-effective than conventional EBRT or RFA. Conventional EBRT remains a cost-effective treatment for patients with poor expected survival.

Phase II Prospective, Open-Label Randomized Controlled Trial Comparing Standard of Care Chemotherapy With and Without Sequential Cytoreductive Interventions for Patients with Oligometastatic Foregut Adenocarcinoma and Undetectable Circulating Tumor Deoxyribose Nucleic Acid (ctDNA) Levels

BACKGROUND

Metastatic adenocarcinomas of foregut origin are aggressive and have limited treatment options, poor quality of life, and a dismal prognosis. A subset of such patients with limited metastatic disease might have favorable outcomes with locoregional metastasis-directed therapies. This study investigates the role of sequential cytoreductive interventions in addition to the standard of care chemotherapy in patients with oligometastatic foregut adenocarcinoma.

METHODS

This is a single-center, phase II, open-label randomized clinical trial. Eligible patients include adults with synchronous or metachronous oligometastatic (metastasis limited to two sites and amenable for curative/ablative treatment) adenocarcinoma of the foregut without progression after induction chemotherapy and having undetectable ctDNA. These patients will undergo induction chemotherapy and will then be randomized (1:1) to either sequential curative intervention followed by maintenance chemotherapy versus routine continued chemotherapy. The primary endpoint is progression-free survival (PFS), and a total of 48 patients will be enrolled to detect an improvement in the median PFS in the intervention arm with a hazard ratio (HR) of 0.5 with 80% power and a one-sided alpha of 0.1. Secondary endpoints include disease-free survival (DFS) in the intervention arm, overall survival (OS), ctDNA conversion rate pre/post-induction chemotherapy, ctDNA PFS, PFS2, adverse events, quality of life, and financial toxicity.

DISCUSSION

This is the first randomized study that aims to prospectively evaluate the efficacy and safety of surgical/ablative interventions in patients with ctDNA-negative oligometastatic adenocarcinoma of foregut origin post-induction chemotherapy. The results from this study will likely develop pertinent, timely, and relevant knowledge in oncology.

Oncologic outcomes according to the level of disease burden in patients with metachronous distant metastases from uterine cervical cancer: a Korean Radiation Oncology Group study (KROG 18-10)

Objective

This study aimed to evaluate the oncologic outcomes according to disease burden in uterine cervical cancer patients with metachronous distant metastases.

Methods

Between 2005 and 2015, 163 patients with metachronous distant metastases from uterine cervical cancer after receiving a definitive therapy were evaluated at seven institutions in Korea. Low metastatic burden was defined as less than 5 metastatic sites, whereas high metastatic burden was others. Each metastasis site was divided based on the lymph node (LN) and organs affected. The overall survival (OS) and progression-free survival (PFS) were assessed. Cox proportional hazards models, including other clinical variables, were used to evaluate the survival outcomes.

Results

The median follow-up duration was 22.2 months (range: 0.3–174.8 months). Para-aortic LNs (56.4%), lungs (26.4%), supraclavicular LNs (18.4%), and peritoneum (13.5%) were found to be the common metastasis sites. Among 37 patients with a single metastasis, 17 (45.9%) had LN metastases and 20 (54.1%) had organ metastases. The 1- and 2-year OS rates were 73.9% and 55.0%, respectively, whereas the PFS rates were 67.2% and 42.9%, respectively. SCC Ag after recurrence and high metastatic burden were significant factors affecting the OS (p=0.004 and p<0.001, respectively). Distant organ recurrence, short disease-free interval (≤2 years), and high metastatic burden were unfavorable factors for PFS (p=0.003, p=0.011, and p=0.002, respectively).

Conclusion

A favorable oncologic outcome can be expected by performing salvage treatments in selected patients with a long disease-free interval, low metastatic burden, and/or lymphatic-only metastasis.

This multicenter study aimed to evaluate the oncologic outcomes according to disease burden in uterine cervical cancer patients with metachronous distant metastases. Long disease-free interval, low metastatic burden, and/or lymphatic-only metastasis are good prognostic factors for metachronous distant metastatic cervical cancer.

Identifying nasopharyngeal carcinoma patients with metachronous metastasis sensitive to local treatment: a real-world study

It is difficult for physicians to identify patients with metastatic nasopharyngeal carcinoma (NPC) who are sensitive to local treatment of metastases. Here, we aimed to establish a prognostic model for survival and individualize treatments for patients with metastatic NPC. Data were collated from 240 NPC patients diagnosed with metachronous metastasis between 2006 and 2020 who received palliative chemotherapy with or without local treatment. Multivariable Cox regression was implemented to construct a nomogram which had a concordance index of 0.764 when predicting 1-, 3-, and 5-year overall survival (OS). We then classified patients according to risk, creating low- and high-risk groups using the nomogram. Differences in OS between the two groups were significant (P<0.001). In the low-risk group, the OS for patients who received local treatment was longer than those without (P=0.009). This novel nomogram shows good performance in classifying patients according to risk and may also be a promising tool for determining who responds best to local treatment. Further validation using external center data is warranted.

A Systematic Review of Patients' Values, Preferences, and Expectations for the Treatment of Metastatic Prostate Cancer

CONTEXT

Advances in systemic agents have increased overall survival for men diagnosed with metastatic prostate cancer. Additional cytoreductive prostate treatments and metastasis-directed therapies are under evaluation. These confer toxicity but may offer incremental survival benefits. Thus, an understanding of patients' values and treatment preferences is important for counselling, decision-making, and guideline development.

OBJECTIVE

To perform a systematic review of patients' values, preferences, and expectations regarding treatment of metastatic prostate cancer.

EVIDENCE ACQUISITION

The MEDLINE, Embase, and CINAHL databases were systematically searched for qualitative and preference elucidation studies reporting on patients' preferences for treatment of metastatic prostate cancer. Certainty of evidence was assessed using Grading of Recommendation, Assessment, Development and Evaluation (GRADE) or GRADE Confidence in the Evidence from Reviews of Qualitative Research (CERQual). The protocol was registered on PROSPERO as CRD42020201420.

EVIDENCE SYNTHESIS

A total of 1491 participants from 15 studies met the prespecified eligibility for inclusion. The study designs included were discrete choice experiments (n = 5), mixed methods (n = 3), and qualitative methods (n = 7). Disease states reported per study were: metastatic castration-resistant prostate cancer in nine studies (60.0%), metastatic hormone-sensitive prostate cancer in two studies (13.3%), and a mixed cohort in four studies (26.6%). In quantitative preference elicitation studies, patients consistently valued treatment effectiveness and delay in time to symptoms as the two top-ranked treatment attributes (low or very low certainty). Patients were willing to trade off treatment-related toxicity for potential oncological benefits (low certainty). In qualitative studies, thematic analysis revealed cancer progression and/or survival, pain, and fatigue as key components in treatment decisions (low or very low certainty). Patients continue to value oncological benefits in making decisions on treatments under qualitative assessment.

CONCLUSIONS

There is limited understanding of how patients make treatment and trade-off decisions following a diagnosis of metastatic prostate cancer. For appropriate investment in emerging cytoreductive local tumour and metastasis-directed therapies, we should seek to better understand how this cohort weighs the oncological benefits against the risks.

PATIENT SUMMARY

We looked at how men with advanced (metastatic) prostate cancer make treatment decisions. We found that little is known about patients' preferences for current and proposed new treatments. Further studies are required to understand how patients make decisions to help guide the integration of new treatments into the standard of care.

Results of Radiation Therapy as Local Ablative Therapy for Oligometastatic Non-Small Cell Lung Cancer

Oligometastatic cancer is characterized by a limited number of metastatic deposits. Compared with lung cancer patients who have more widespread disease, oligometastatic lung cancer patients have more favorable survival outcomes. Therefore, it has been hypothesized that local ablative therapy (LAT) directed at the metastatic deposits in addition to standard-of-care systemic therapy may further improve survival outcomes in oligometastatic lung cancer patients. One LAT modality that has been utilized in oligometastatic lung cancer is radiation therapy. In particular, ultra-hypofractionated radiotherapy, also known as stereotactic body radiotherapy (SBRT), has been shown to provide excellent local control with a favorable safety profile. Here, we reviewed the retrospective studies and prospective trials that have deployed radiation therapy as LAT in oligometastatic lung cancer, including randomized studies showing benefits for progression-free survival and overall survival with the addition of LAT. We also discuss the impact of targeted therapies and immunotherapy on radiation as LAT.

Study protocol of an open-label, single arm phase II trial investigating the efficacy, safety and quality of life of neoadjuvant chemotherapy with liposomal irinotecan combined with Oxaliplatin and 5-fluorouracil/Folinic acid followed by curative surgical resection in patients with hepatic Oligometastatic adenocarcinoma of the pancreas (HOLIPANC)

BACKGROUND

According to current guidelines, treatment of patients with hepatic oligometastasis in pancreatic cancer is not reflected and systemic chemotherapy is recommended in those patients. Retrospective data suggest beneficial outcomes in patients with hepatic oligometastasis, though prospective data from clinical trials addressing this particular patient group is not available.

METHODS

In this single arm, phase-2 trial, survival data from patients receiving neoadjuvant chemotherapy followed by R0/R1 resection will be compared to historic data from patients with oligometastatic adenocarcinoma of the pancreas. The clinical trial will focus on a well-defined patient collective with metastatic load limited to the liver as target organ with a maximum of five metastases. The combination of liposomal irinotecan (nal-IRI), oxaliplatin (OX) and 5-fluouracil (5-FU)/folinic acid (FA) (nal-IRI + OX+ 5-FU/FA, NAPOX) was chosen as neoadjuvant chemotherapy; the choice was based on an ongoing clinical study in which NAPOX appeared manageable, with promising anti-tumor activity in first-line treatment of patients with metastatic pancreatic adenocarcinoma. In total 150 patients will be enrolled for this trial with an aim of 55 patients receiving a complete macroscopic synchronous tumor and metastatic resection.

DISCUSSION

This is the first clinical study to prospectively evaluate the value of multimodality therapy concepts in oligometastatic pancreatic cancer.

TRIAL REGISTRATION NUMBERS

EudraCT 2019-002734-37 ; NCT04617457 .

Metastasis-Directed Radiotherapy for Oligoprogressive or Oligopersistent Metastatic Colorectal Cancer

INTRODUCTION

Some patients with cancer may present with progressive or persistent disease at a limited number of sites following a period of treatment response. We evaluated the safety and effectiveness of metastasis-directed radiotherapy (MRT) for oligoprogressive or oligopersistent disease in patients receiving systemic treatment for metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

Patients with mCRC who received 5-fluorouracil, leucovorin, and oxaliplatin; 5-fluorouracil, leucovorin, and irinotecan; and/or capecitabine chemotherapy between 2011 and 2020 at a single institution were identified. Then, those who underwent MRT for five or fewer lesion sites while receiving systemic treatment for other metastases were categorized. The primary endpoint was time to change to systemic therapy. Secondary endpoints included MRT-related toxicity, overall survival, and local control.

RESULTS

Among 4157 patients included, 91 (2%) received MRT to limited lesion sites (55 oligoprogressive and 36 oligopersistent) during systemic treatment following a period of treatment response. The median time to change to next-line systemic therapy was 5 months in the overall cohort (measured from the current chemotherapy session) and 9.5 (range, 6.0-40.6) months in the MRT group (measured from the MRT session). No severe toxicity or systemic treatment interruption was observed following MRT. The 1-year local control and overall survival rates were 69% and 99%, respectively.

CONCLUSION

In patients with oligoprogressive or oligopersistent mCRC, MRT may be performed safely in conjunction with systemic treatment to maximize the benefit of systemic therapy and to prolong the time to change to systemic therapy. Further prospective studies should confirm these findings.

Metastatic prostate cancer men's attitudes towards treatment of the local tumour and metastasis evaluative research (IP5-MATTER): protocol for a prospective, multicentre discrete choice experiment study

INTRODUCTION

Systemic therapy with androgen deprivation therapy (ADT) and intensification with agents such as docetaxel, abiraterone acetate and enzalutamide has resulted in improved overall survival in men with de novo synchronous metastatic hormone-sensitive prostate cancer (mHSPC). Novel local cytoreductive treatments and metastasis-directed therapy are now being evaluated. Such interventions may provide added survival benefit or delay the requirement for further systemic agents and associated toxicity but can confer additional harm. Understanding men's preferences for treatment options in this disease state is crucial for patients, clinicians, carers and future healthcare service providers.

METHODS

Using a prospective, multicentre discrete choice experiment (DCE), we aim to determine the attributes associated with treatment that are most important to men with mHSPC. Furthermore, we plan to determine men's preferences for, and trade-offs between, the attributes (survival and side effects) of different treatment options including systemic therapy, local cytoreductive approaches (external beam radiotherapy, cytoreductive radical prostatectomy or minimally invasive ablative therapy) and metastases-directed therapies (metastasectomy or stereotactic ablative body radiotherapy). All men with newly diagnosed mHSPC within 4 months of commencing ADT and WHO performance status 0-2 are eligible. Men who have previously consented to a cytoreductive treatment or have developed castrate-resistant disease will be excluded. This study includes a qualitative analysis component, with patients (n=15) and healthcare professionals (n=5), to identify and define the key attributes associated with treatment options that would warrant trade-off evaluation in a DCE. The main phase component planned recruitment is 300 patients over 1 year, commencing in January 2021, with planned study completion in March 2022.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Health Research Authority East of England, Cambridgeshire and Hertfordshire Research Ethics Committee (Reference: 20/EE/0194). Project information will be reported on the publicly available Imperial College London website and the Heath Economics Research Unit (HERU website including the HERU Blog). We will use the social media accounts of IP5-MATTER, Imperial Prostate London, HERU and the individual researchers to disseminate key findings following publication. Findings from the study will be presented at national/international conferences and peer-reviewed journals. Authorship policy will follow the recommendations of the International Committee of Medical Journal Editors.

TRIAL REGISTRATION NUMBER

NCT04590976.

[Synchronous oligometastatic renal cell carcinoma-what is the role of surgery?]

BACKGROUND

Long-term remission can be achieved by surgery in patients with metastatic renal cell carcinoma (mRCC), without chronic toxicity due to systemic treatment. Data on metastasectomy are mostly based on observations of metachronous metastasis. However, it is unclear whether patients with synchronous oligometastasis may also benefit from surgery alone as an alternative to highly effective systemic treatment combined with resection of the primary tumor.

MATERIALS AND METHODS

The authors performed an unstructured literature search in PubMed including systematic reviews and meta-analyses. Results are discussed in regard of the current data and clinical practice.

RESULTS AND DISCUSSION

Although there is no uniform definition for oligometastasis in mRCC, cytoreductive nephrectomy in selected patients seems to be mandatory before metastasectomy is performed in primary oligometastatic RCC. In particular, in those patients with oligometastasis of the lung, bone, central nervous system, liver, adrenal gland, and thyroid, metastasectomy appears to be an important therapeutic option. Ultimately, among the therapeutic options, surgery is also an important therapeutic approach in primary oligometastatic mRCC. A balanced consideration between surgery, other local therapies, and modern systemic treatment demands interdisciplinary decision-making that takes into account the patients' preference.

Optimal Treatment for Patients with Oligometastatic Prostate Cancer

Oligometastatic prostate cancer (PCa) can be defined as cancer with a limited number of metastases, typically fewer than 5 lesions, and involves lesions contained within the axial versus the appendicular skeleton. Patients can present with de novo oligometastatic, oligorecurrent, or oligoprogressive PCa. Oligometastatic PCa patients demonstrate considerable improvements in survival outcomes, with a better prognosis than patients with extensive metastatic disease. However, the management of patients that present with nonsymptomatic oligometastatic PCa remains difficult. In the oligometastatic setting, the benefit of local therapies such as prostatectomy and radiotherapy on survival outcomes is an intriguing topic; however, their impact on oncological outcomes is still unknown.

Salvage lymph node dissection for prostate-specific membrane antigen (PSMA) positron emission tomography (PET)-identified oligometastatic disease

INTRODUCTION

The availability of prostate-specific membrane antigen (PSMA) positron emission tomography (PET)/computed tomography (CT) imaging, particularly in the setting of rising prostate-specific antigen (PSA) after definitive treatment, has led to oligometastatic prostate cancer being increasingly identified. Despite the enthusiasm surrounding treating oligometastatic disease, it has been relatively understudied. We sought to review our salvage lymphadenectomy experience in the PSMA PET/CT era.

METHODS

We retrospectively reviewed patients undergoing lymphadenectomy following curative-intent primary therapy with rising PSA who had undergone a PSMA PET/CT identifying oligometastatic disease (defined as ≤5 PSMA-avid lesions) between January 2016 and April 2020. The primary endpoint was complete response, defined as achieving a PSA <0.2 ng/ml without concomitant androgen deprivation therapy (ADT).

RESULTS

Twenty-two patients were included. Primary curative therapy included radical prostatectomy (86.4%) and brachytherapy (13.6%). Median PSA at salvage surgery was 1.72 ng/ml. Pelvic lymph node dissection was the most performed procedure (72.7%). Median node yield was 10.5, with a median of 1.5 positive nodes on pathology. Eight patients (36.4%) achieved PSA <0.2, with six (27.3%) remaining with PSA <0.2 after a median followup of 23.1 months. Nine (40.9%) had an initial PSA decline, but nadired ≥0.2, and in five (22.7%) the PSA rose immediately after surgery. Overall, ADT was started in seven patients (31.8%) at a median of 10.1 months post-salvage surgery.

CONCLUSIONS

In our series of salvage dissection for PSMA-PET-detected nodal oligometastases, approximately a third achieved PSA <0.2; yet, it was only durable in 27%. Prospective trials of salvage nodal radiation are ongoing, however, more prospective trials of salvage node dissection are needed.

Prognostic factors for bone metastases from head and neck squamous cell carcinoma: A case series of 97 patients

Although bone is the second-most frequent site of distant metastases of head and neck squamous cell carcinoma (HNSCC), variable prognostic factors in patients with bone metastases from HNSCC have not been fully investigated. The aim of the present study was to assess the prognostic factors affecting overall survival (OS) in these patients. The medical records of 97 patients at two institutions who developed bone metastases from HNSCC between January 2010 and December 2020 were retrospectively reviewed. A multivariate analysis using a Cox proportional hazards model was performed to identify potential clinical predictive factors for longer OS. The median OS was 7 months, and the 1- and 2-year OS rates for all patients were 35.4 and 19.2%, respectively. The independent predictive factors for longer OS were single bone metastasis, good performance status and administration of systemic chemotherapy. The median OS with each predictor was 10, 10 and 10.5 months, respectively. In a selected group of patients with these three factors, the OS was 14.5 months. In conclusion, single bone metastasis, a good performance status and systemic chemotherapy were independent predictors of longer OS in patients with HNSCC, but their contributions were limited.

The decreased platelet-to-lymphocyte ratio could predict a good prognosis in patients with oligometastatic colorectal cancer: a single-center cohort retrospective study

BACKGROUND

Inflammation markers have an important effect on tumor proliferation, invasion, and metastasis. Oligometastatic disease (OMD) is an intermediate state between widespread metastases and locally confined disease, where curative strategies may be effective for some patients. We aimed to explore the predictive value of inflammatory markers in patients with oligometastatic colorectal cancer (OMCC) and build a nomogram to predict the prognosis of these patients.

METHODS

Two hundred nine patients with OMCC were retrospectively collected in this study. The Kaplan-Meier survival curves and Cox regression analysis were used to estimate overall survival (OS) and progression-free survival (PFS). A multivariate Cox analysis model was utilized to establish the nomogram. The concordance index (C-index), calibration curve, and receiver operating characteristics (ROC) were established to verify the validity and accuracy of the prediction model.

RESULTS

According to the multivariate analysis, decreased platelet-to-lymphocyte ratio (PLR) might independently improve OS in patients with OMCC (HR = 2.396, 95% CI 1.391-4.126, P = 0.002). Metastases of extra-regional lymph nodes indicated poor OS (HR = 2.472, 95% CI 1.247-4.903, P = 0.010). While the patients with early N stage had better OS (HR = 4.602, 95% CI 2.055-10.305, P = 0.001) and PFS (HR = 2.100, 95% CI 1.364-3.231, P = 0.007). Primary tumor resection (HR = 0.367, 95% CI 0.148-0.908, P = 0.030) and lower fibrinogen (HR = 2.254, 95% CI 1.246-4.078, P = 0.007) could significantly prolong the OS in patients with OMCC. PLR, metastases of extra-regional lymph nodes, N stage, primary tumor resection, and fibrinogen were used to make up the nomogram. The C-index and area under the curve (AUC) of the ROC in nomogram were 0.721 and 0.772 respectively for OS, showed good consistency between predictive probability of OS and actual survival.

CONCLUSIONS

Decreased PLR could predict a good prognosis in patients with OMCC. The nomogram including inflammatory factors and clinicopathological markers was credible and accurate to predict survivals in patients with OMCC.

Survival impact of concurrent chemoradiotherapy for elderly patients with synchronous oligometastatic esophageal squamous cell carcinoma: A propensity score matching and landmark analyses

PURPOSE

To evaluate the potential benefits of concurrent chemoradiotherapy (CCRT), and to establish a nomogram for predicting survival outcomes of elderly patients with synchronous oligometastatic esophageal squamous cell carcinoma (SOEC).

MATERIALS AND METHODS

This study eventually enrolled 314 elderly patients who initially diagnosed with SOEC from two centers. Treatment responses and outcomes of 151 patients receiving CCRT and 163 patients undergoing chemotherapy alone (CT) were compared. Propensity score matching and landmark analyses were performed to control potential confounding factors. A nomogram was established on the basis of the Cox regression model.

RESULTS

After a median follow-up of 42.3 months, CCRT was superior to CT alone in objective response rate (ORR, 59.6% vs. 39.9%, P < 0.001), median progression-free survival (PFS, 10.0 vs. 7.2 months, P < 0.001), and median overall survival (OS, 18.5 vs. 15.6 months, P < 0.001). The propensity score matching (PSM) and landmark analyses redemonstrated the same trend (P < 0.01). On hierarchical analysis, patients with 1-3 metastatic lesions involving one organ displayed longer median PFS (9.0 vs. 7.8 months, P = 0.008) and OS (17.8 vs. 15.2 months, P < 0.001) than those with 4-5 metastatic lesions involving 2-3 organs. The major toxicities of grade III or higher for CCRT included leukocytopenia (23.2%), radiation esophagitis (7.3%), and radiation pneumonitis (8.6%). Cox multivariate analysis showed that the number of metastatic lesions (P = 0.012) and tumor response (P < 0.001) were independent prognostic factors associated with OS. A nomogram was established by incorporating the number of metastatic lesions and tumor response, with a concordance index of 0.743 after internal cross-validation. Calibration curves and decision curve analysis confirmed that nomogram had a favorable predictive value for individualized survival.

CONCLUSIONS

Compared with CT alone, CCRT exhibited superior efficacy and acceptable toxicity in the first-line treatment for elderly patients with SOEC. The current study supports the oligometastatic definition of ≤3 metastatic lesions involving one organ for esophageal cancer patients. The constructed nomogram can effectively predict the individualized survival.

Breast cancer patients with isolated bone metastases and oligometastatic bone disease show different survival outcomes

In this study, we planned to investigate the clinical course of patients with breast cancer with oligometastatic bone disease (OMBD). The patients were grouped according to the characteristics and the sites of metastases. Group I included 928 patients without metastasis. Group II, the OMBD group, included 68 patients. Group III, the widespread metastasis group, comprised 185 patients with multiple bone metastases and/or solid organ metastases. The mean overall survival of the groups was 16.7 ± 0.3 years in group 1, and 7.8 ± 0.8 and 5.9 ± 0.4 years in groups 2 and 3, respectively (p < 0.001 for the comparison of all three groups together; p < 0.001 for group 1 vs. 2 and 3) and (p = 0.037 for group 2 vs. group 3). In the subgroup survival analysis of patients in group 2 (OMBD), the mean and median survival was 5.5 ± 0.8 and 4.0 ± 0.8 years vs. 9.2 ± 0.98 and 9.0 ± 1.05 years in patients with more than one bone metastasis and single bone metastasis, respectively (p = 0.019). OMBD seems to be a different disease than breast cancer with isolated bone metastases. The high risk of developing OMBD, especially following locoregional recurrence, increases the importance of locoregional therapy in large T and N stage tumors.

Reirradiation With Stereotactic Radiosurgery After Local or Marginal Recurrence of Brain Metastases From Previous Radiosurgery

PURPOSE

Brain metastases represent a major indication for stereotactic radiosurgery (SRS), but further study is needed regarding repeat SRS (SRS2) after local or marginal recurrence after prior SRS (SRS1). We report local tumor control (LC) after SRS2 and identify predictors of radiation necrosis (RN) and symptomatic RN (SRN).

METHODS AND MATERIALS

Patients had biopsy-proven non-small cell lung cancer and at least 1 brain metastasis previously treated with SRS. SRS2 was performed from 2015 to 2020 and required overlap of the prescription isodose lines with those from SRS1. Patients treated with preoperative SRS were excluded. Primary endpoints were LC by Response Assessment in Neuro-oncology criteria, RN, and SRN.

RESULTS

From 8 institutions, 102 patients with 123 treated lesions were included. SRS2 was performed at a median 12 months after SRS1. SRS2 delivered a median 18 Gy (interquartile range [IQR], 16-18) margin dose to the 50% (IQR, 50%-70%) isodose line, maximum dose of 30.5 Gy (IQR, 25.0-36.0), and V12Gy of 3.38 cm³ (IQR, 0.83-7.64). One-year and 2-year LC were 79% and 72%, respectively. Local tumor control was improved with tumor volume ≤1 cm³ (P < .005). There were 25 (20%) cases of RN and 9 (7%) cases of SRN. For SRS1 and SRS2, SRN rates were higher with maximum doses ≥40 Gy or SRS2 V12Gy >9 cm³ (P < .025 for each). SRS1 and SRS2 maximum dose ≥40 Gy was also predictive of increased RN (P < .05 for each). Prior immunotherapy was not predictive of RN or SRN.

CONCLUSIONS

Repeat SRS afforded a high rate of local tumor control and a low rate of SRN. At SRS2, V12Gy ≤9 cm³ and maximum dose <40 Gy may reduce the risks of RN and SRN. These results are most applicable to lesions with approximately 1 cm³ volume and 1-year interval between SRS courses.

Diagnosis, biology and epidemiology of oligometastatic breast cancer

Does oligometastatic breast cancer (OMBC) deserve a dedicated treatment? Although some authors recommend multidisciplinary management of OMBC with a curative intent, there is no evidence proving this strategy beneficial in the absence of a randomized trial. The existing literature sheds little light on OMBC. Incidence is unknown; data available are either obsolete or biased; there is no consensus on the definition of OMBC and metastatic sites, nor on necessary imaging techniques. However, certain proposals merit consideration. Knowledge of eventual specific OMBC biological characteristics is limited to circulating tumor cell (CTC) counts. Given the data available for other cancers, studies on microRNAs (miRNAs), circulating tumor DNA (ctDNA) and genomic alterations should be developed Finally, safe and effective therapies do exist, but results of randomized trials will not be available for many years. Prospective observational cohort studies need to be implemented.

Investigation of the Definition of De Novo Oligometastatic Nasopharyngeal Carcinoma: A Retrospective Study

Background

The prognosis of metastatic nasopharyngeal carcinoma (mNPC) is highly heterogeneous. As a special stage of distant metastasis of mNPC, quite a few oligometastatic NPC (omNPC) patients can still achieve a long-term survival after treatment. However, there is no uniform standard for the definition of omNPC until now.

Methods

We retrospectively analyzed the survival data of 191 patients with de novo mNPC at the Affiliated Cancer Hospital and Institute of Guangzhou Medical University between 2010 and 2017 and specifically analyzed the clinical outcomes associated with the number of metastatic organs/lesions and tried to find a cohort with relatively better prognosis to define as omNPC.

Results

The median overall survival (OS) of the entire group of patients was 21.5 months (95% CI 15.0–28.0), and the 1-year, 2-year, and 3-year OS rates were 72.2%, 46.1%, and 34.3%, respectively. Multiple-organ metastases (P < 0.001) and >5 metastatic lesions (P < 0.001) were adverse influencing factors of prognosis, and the number of metastatic lesions (P < 0.001) was the independent factor influencing the prognosis of de novo mNPC. The overall survival (OS) and progression-free survival (PFS) of patients with ≤5 metastatic lesions were significantly better than those of patients with >5 metastatic lesions.

Conclusion

Patients with ≤5 metastatic lesions presented a better survival, and this criterion may be a definition standard for the de novo omNPC.

Classifying Oligometastatic Non-Small Cell Lung Cancer

An oligometastatic cancer state was first postulated in the 1990s by Hellman and Weichselbaum and described limited metastatic spread to a single or few sites of disease. It was hypothesized that this metastatic entity falls along a continuum of the natural history of cancer progression from a localized primary tumor to widespread metastases. Support for oligometastatic non-small cell lung cancer (NSCLC) has since been provided by multiple retrospective studies and then prospective randomized trials demonstrating better survival in this patient population after aggressive consolidative treatment. However, the lack of a universal definition of oligometastatic NSCLC has hindered a comparison between different studies and prevented well-defined recommendations for local consolidative treatment in this patient population. Attempts have been made to establish a common definition for use in clinical management and for the identification of inclusion criteria for future trials. In this review, we seek to summarize the current definitions of oligometastatic NSCLC based on recent expert consensus statements, previous randomized trials, and current treatment guidelines and to highlight the continued variability in current practice.

A priori quality assurance using a benchmark case of the randomized phase 2 GORTEC 2014-14 in oligometastatic head and neck cancer patients

PURPOSE

A Benchmark Case (BC) was performed as part of the quality assurance process of the randomized phase 2 GORTEC 2014-14 OMET study, testing the possibility of multisite stereotactic radiation therapy (SBRT) alone in oligometastatic head and neck squamous cell carcinoma (HNSCC) as an alternative to systemic treatment and SBRT.

MATERIAL AND METHODS

Compliance of the investigating centers with the prescription, delineation, planning and evaluation recommendations available in the research protocol was assessed. In addition, classical dosimetric analysis was supplemented by quantitative geometric analysis using conformation indices.

RESULTS

Twenty centers participated in the BC analysis. Among them, four major deviations (MaD) were reported in two centers. Two (10%) centers in MaD had omitted the satellite tumor nodule and secondarily validated after revision. Their respective DICE indexes were 0.37 and 0 and use of extracranial SBRT devices suboptimal There were significant residual heterogeneities between participating centers, including those with a similar SBRT equipment, with impact of plan quality using standard indicators and geometric indices.

CONCLUSION

A priori QA using a BC conditioning the participation of the clinical investigation centers showed deviations from good SBRT practice and led to the exclusion of one out of the twenty participating centers. The majority of centers have demonstrated rigorous compliance with the research protocol. The use of quality indexes adds a complementary approach to improve assessment of plan quality.

MYC levels regulate metastatic heterogeneity in pancreatic adenocarcinoma

The degree of metastatic disease varies widely amongst cancer patients and impacts clinical outcomes. However, the biological and functional differences that drive the extent of metastasis are poorly understood. We analyzed primary tumors and paired metastases using a multi-fluorescent lineage-labeled mouse model of pancreatic ductal adenocarcinoma (PDAC) - a tumor type where most patients present with metastases. Genomic and transcriptomic analysis revealed an association between metastatic burden and gene amplification or transcriptional upregulation of MYC and its downstream targets. Functional experiments showed that MYC promotes metastasis by recruiting tumor associated macrophages (TAMs), leading to greater bloodstream intravasation. Consistent with these findings, metastatic progression in human PDAC was associated with activation of MYC signaling pathways and enrichment for MYC amplifications specifically in metastatic patients. Collectively, these results implicate MYC activity as a major determinant of metastatic burden in advanced PDAC.

Palliative Radiation for Cancer Pain Management

Bone metastases are the most common cause of cancer-related pain. Radiation therapy (RT) is a very common and effective treatment to relieve pain. Conventionally fractionated RT typically consists of the following regimens: 8 Gy in a single treatment, 20 Gy in five fractions, 24 Gy in six fractions, or 30 Gy in ten fractions. All treatment regimens have similar rates of pain relief (range 50-80%), with single-fraction treatment often requiring retreatment. While many painful bony metastases can be managed with RT alone, some may be more complex, often requiring multidisciplinary management, including the need for surgical stabilization or augmentation prior to RT. There are multiple assessment tools including the neurologic, oncologic, mechanical, and systemic (NOMS) decision framework, which allows clinicians to assess the proper course of treatment for these patients. For patients with good prognosis, oligometastatic disease, or those presenting with more radioresistant tumors, stereotactic body radiotherapy (SBRT) may be another option, which offers ablative doses of radiation delivered over several treatments. This chapter reviews the fundamentals of RT for palliation.

Radiation Therapy Planning of Thoracic Tumors: A Review of Challenges Associated With Lung Toxicities and Potential Perspectives of Gallium-68 Lung PET/CT Imaging

Despite the introduction of new radiotherapy techniques, such as intensity modulated radiation therapy or stereotactic body radiation therapy, radiation induced lung injury remains a significant treatment related adverse event of thoracic radiation therapy. Functional lung avoidance radiation therapy is an emerging concept in the treatment of lung disease to better preserve lung function and to reduce pulmonary toxicity. While conventional ventilation/perfusion (V/Q) lung scintigraphy is limited by a relatively low spatial and temporal resolution, the recent advent of ⁶⁸Gallium V/Q lung PET/CT imaging offers a potential to increase the accuracy of lung functional mapping and to better tailor lung radiation therapy plans to the individual's lung function. Lung PET/CT imaging may also improve our understanding of radiation induced lung injury compared to the current anatomical based dose–volume constraints. In this review, recent advances in radiation therapy for the management of primary and secondary lung tumors and in V/Q PET/CT imaging for the assessment of functional lung volumes are reviewed. The new opportunities and challenges arising from the integration of V/Q PET/CT imaging in radiation therapy planning are also discussed.

Stepwise-Hierarchical Pooled Analysis for Synergistic Interpretation of Meta-analyses Involving Randomized and Observational Studies: Methodology Development

Background

The necessity of including observational studies in meta-analyses has been discussed in the literature, but a synergistic analysis method for combining randomized and observational studies has not been reported. Observational studies differ in validity depending on the degree of the confounders’ influence. Combining interpretations may be challenging, especially if the statistical directions are similar but the magnitude of the pooled results are different between randomized and observational studies (the ”gray zone”).

Objective

To overcome these hindrances, in this study, we aim to introduce a logical method for clinical interpretation of randomized and observational studies.

Methods

We designed a stepwise-hierarchical pooled analysis method to analyze both distribution trends and individual pooled results by dividing the included studies into at least three stages (eg, all studies, balanced studies, and randomized studies).

Results

According to the model, the validity of a hypothesis is mostly based on the pooled results of randomized studies (the highest stage). Ascending patterns in which effect size and statistical significance increase gradually with stage strengthen the validity of the hypothesis; in this case, the effect size of the observational studies is lower than that of the true effect (eg, because of the uncontrolled effect of negative confounders). Descending patterns in which decreasing effect size and statistical significance gradually weaken the validity of the hypothesis suggest that the effect size and statistical significance of the observational studies is larger than the true effect (eg, because of researchers’ bias).

Conclusions

We recommend using the stepwise-hierarchical pooled analysis approach for meta-analyses involving randomized and observational studies.

Oligometastatic Adenocarcinoma of the Esophagus: Current Understanding, Diagnosis, and Therapeutic Strategies

Esophageal adenocarcinoma is an aggressive cancer of increasing incidence and is associated with poor prognosis. The early recognition of synchronous and metachronous oligometastasis in esophageal adenocarcinoma may allow for prompt intervention and potentially improved survival. However, curative approaches to oligometastatic esophageal disease remain unproven and may represent an area of emerging divergence of opinion for surgical and medical oncologists. We sought to identify the current understanding and evidence for management of oligometastatic esophageal adenocarcinoma by performing a thorough review of the available literature.

Radiotherapy for oligometastatic non-small cell lung cancer: a narrative review

Preclinical and early clinical evidence suggest that radical radiotherapy of oligometastatic disease in non-small cell lung cancer (NSCLC) patients can impact outcomes with relatively limited toxicity. Whilst data from phase 2 randomized trials suggesting an improved overall survival (OS) with this treatment is promising, it has also illustrated the heterogeneity in this patient population and treatment. Oligometastatic disease in itself comprises a broad spectrum of patients, in terms of tumor load and location, stage of the disease and treatment history. This real-life variety in patient characteristics is often reflected in studies to a certain extent, hinting to the fact that all might benefit from radical radiotherapy to limited metastatic disease, yet leaving the question unanswered as to whom the ideal candidate is. Furthermore, differences between and within studies with regards to treatment modality, timing, radiation technique, and radiation dose are substantial. Also, preclinical and early clinical trials suggest that radiotherapy can work synergistically with checkpoint inhibitors by acting as an in situ cancer vaccine, therefore the combination of these two treatments in oligometastatic patients might entail the largest benefit. Ongoing randomized controlled phase 3 trials and prospective registry trials will further elucidate the true extent of benefit of this local treatment strategy and aid in identifying the ideal patient population and therapy. The current narrative review summarizes the clinical evidence on radiotherapy for oligometastatic NSCLC and highlights the remaining unknowns.

Oligometastatic prostate cancer: definition and the role of local and systemic therapy: a narrative review

The definition of oligometastatic prostate cancer (OMPC) includes a heterogenous group of disease states, mostly defined by the number and site of metastases, which seems to be biologically different to widespread tumors. Evidence suggests a substantial survival benefit for this subgroup of limited metastatic burden which is currently seen as a potentially curable disease and therefore with an increasing interest in the scientific community. As there is still no consensus on the definition of OMPC, commonly used criteria are based on the CHAARTED and LATITUDE trials. The management algorithms for these patients were rapidly changing in the past decade due to recent data with a paradigm shift to a multimodal intensification of the treatment by the availability of combinations of hormonal therapy with taxane-based chemotherapy and androgen-receptor-targeted agents leading to significant improvement of clinical outcomes. In addition, radiotherapy of the primary tumor is associated with significant survival benefit in patients with OMPC establishing a new arm in the multimodal treatment concept. Recent data on metastases directed therapy and cytoreductive prostatectomy showed promising results, while there is still a lack of prospective trials and therefore should be limited to experimental settings. The purpose of this review is to summarize and discuss the existing data on treatment of OMPC.

Narrative review: molecular and genetic profiling of oligometastatic non-small cell lung cancer

Objective

The objectives of this review are to discuss: the definition, clinical and biologic features of oligometastatic non-small cell lung cancer (NSCLC), as well as the concept of treating oligoprogression in oligometastatic NSCLC.

Background

A substantial proportion of patients diagnosed with lung cancer present with metastatic disease, and a large portion of patients who present with localized disease later develop metastases. Oligometastatic NSCLC is defined as an intermediate state between localized and widespread metastatic disease, where there may be a role for curative localized therapy approach by treating the primary tumor and all metastases with radiotherapy or surgery. Despite the increasing application of this approach in patients with lung cancer, the identification of patients who might benefit from this approach is yet to be well characterized.

Methods

After a systematic review of the literature, a PubMed search was performed using the English language and the key terms: oligometastatic, non-small cell lung cancer (NSCLC), localized consolidative treatment (LCT), biomarkers, biologic features, clinical features. Over 500 articles were retrieved between 1889–2021. A total of 178 papers discussing the definition, clinical and biologic factors leading to oligometastatic NSCLC were reviewed and included in the discussion of this paper.

Conclusions

Oligometastatic NSCLC is a unique entity. Identifying patients who have oligometastatic NSCLC accurately using a combination of clinical and biologic features and treating them with localized consolidative approach appropriately results in improvement of outcome. Further understanding of the molecular mechanisms driving the formation of oligometastatic NSCLC is an important area of focus for future studies.

Treatment Strategies for Oligometastatic Breast Cancer

OPINION STATEMENT

Oligometastatic breast cancer, typically defined as the presence of 1-5 metastases, represents an intermediate state between locally advanced and widely metastatic disease. Emerging research suggests that oligometastatic cancer has a unique molecular signature distinct from widely metastatic disease, and that it carries a superior prognosis. Owing to its more limited capacity for widespread progression, oligometastatic disease may benefit from aggressive ablative therapy to known metastases. Options for ablation include surgical excision, radiofrequency ablation, and hypofractionated image-guided radiotherapy (HIGRT). The phase II SABR-COMET trial, which enrolled patients with oligometastatic disease of multiple histologies and randomized them to HIGRT vs. standard of care, found a notable survival advantage in favor of HIGRT. Other data suggest that HIGRT may synergize with immunotherapy by releasing powerful cytokines that increase anti-tumor immune surveillance and by recruiting tumor infiltrating lymphocytes, helping to overcome resistance to therapy. There are many ongoing trials exploring the role of ablative therapy, most notably HIGRT, with or without immunotherapy, for the treatment of oligometastatic breast cancer.We believe that patients with oligometastatic breast cancer should be offered enrollment on prospective clinical trials when possible. Outside the context of a clinical trial, we recommend that select patients with oligometastatic breast cancer be offered treatment with a curative approach, including ablative therapy to all sites of disease if it can be safely accomplished. Currently, selection criteria to consider for ablative therapy include longer disease-free interval from diagnosis to metastasis (>2 years), fewer metastases, and fewer involved organs. Undoubtedly, new data will refine or even upend our understanding of the definition and optimal management of oligometastatic disease.

Increased biologically effective dose (BED) to the primary tumor is associated with improved survival in patients with oligometastatic NSCLC

PURPOSE

Local consolidative therapy (LCT) for oligometastatic non-small cell lung cancer (NSCLC) is an evolving treatment paradigm. We investigated whether the biologically effective dose (BED) of consolidative radiation therapy (RT) to the primary tumor predicted for improved local control, progression-free survival (PFS), and overall survival (OS) among NSCLC patients presenting with oligometastatic disease.

MATERIALS AND METHODS

Patients presenting to a single institution (2000-2017) with stage IV NSCLC, ≤3 synchronous metastatic lesions at diagnosis, and treated with RT to the primary tumor were identified. Univariate and multivariable Cox proportional-hazards regression modeling were performed to identify factors associated with local recurrence-free survival (LRFS), PFS, and OS.

RESULTS

One hundred twenty-four patients were identified meeting our inclusion criteria. With a median follow-up of 55.1 months, median PFS and OS for the entire cohort were 11.0 months and 25.3 months, respectively. The median BED (α/β = 10) of RT to the primary tumor was 74.3 Gy. On univariate analysis, increased BED to the primary tumor predicted for improved PFS (p < 0.001) and LRFS (p = 0.01), with a median PFS of 8.5 vs 12.8 months and median LRFS of 23.4 vs 58.4 months between patients treated with BED < 75 Gy and ≥75 Gy, respectively. Increased BED to the primary tumor was also associated with significantly improved OS (p = 0.02); patients treated with a BED of <75 Gy demonstrated a median OS of 22.9 months vs 27.5 months if treated with BED ≥ 75 Gy. On multivariable analysis, primary site BED remained a significant predictor of OS (p = 0.02) and PFS (p = 0.002).

CONCLUSIONS

We found that delivery of >75 Gy BED RT regimens to the primary lesion in patients with synchronous oligometastatic NSCLC is associated with improved local control, PFS, and OS. These data support results of recent prospective trials and other ongoing prospective efforts to characterize therapeutic benefits associated with this management strategy.

Effects of locoregional radiotherapy in de novo metastatic nasopharyngeal carcinoma: A real-world study

•

Locoregional radiotherapy can prolong OS for patients with de novo metastatic nasopharyngeal carcinoma.

•

Nasopharyngeal carcinoma patients with oligometastic disease can benefit from locoregional radiotherapy rather than polymetastatic disease.

Background

To evaluate the value of locoregional radiotherapy (LRRT) in de novo metastatic nasopharyngeal carcinoma (dmNPC) and identify predictive factors for additional LRRT after palliative chemotherapy (PCT).

Methods

Overall survival (OS) was the primary endpoint. Patients who underwent PCT and LRRT were categorized as the PCT+LRRT group; patients who only received palliative chemotherapy were categorized as the PCT group. Oligometastatic diseases (OMD) was defined as ≤5 metastatic lesions and ≤2 metastatic organs.

Results

A total of 168 patients were included for this study. The median OS of patients in the PCT+LRRT group was significantly higher than those in the PCT group (57 months vs. 22 months, P<0.001). Multivariate analyses (MVA) showed that LRRT (HR=0.533, 95% CI: 0.319–0.889, P = 0.016) and OMD (HR=0.548, 95% CI: 0.331–0.907, P = 0.019) were independent prognostic factors for dmNPC. Furthermore, Kaplan–Meier analyses showed that the 3-year OS of patients who received LRRT was significantly better than those who did not receive LRRT in the OMD subgroup (66.3% vs. 25.2%, P<0.001). While, the 3-year OS of patients who received LRRT and without LRRT was no different in the polymetastatic disease (PMD) subgroup (38.9% vs.11.5%, P = 0.115). MVA showed that LRRT was a favorable prognosticator in the OMD subgroup (HR=0.308, 95% CI: 0.159–0.598; P<0.001), and not a favorable prognosticator in the PMD subgroup (HR=0.510, 95% CI: 0.256–1.014, P = 0.055).

Conclusions

LRRT has the potential to prolong OS in NPC patients with de novo OMD. These results suggest that OMD is a potential indicator for filtering beneficiaries from LRRT.

Consolidating radiotherapy with immunotherapy

Radiotherapy and immunotherapy can be concomitantly or sequentially combined seeking synergistic effects in terms of control of irradiated tumors and abscopal effects on non-irradiated lesions. Clinical-trial testing of such combinations faces several obstacles to demonstrate efficacy and needs improvements in trial design, patient selection, evaluation of results and biomarker discovery.

Oligometastatic Lung Cancer Defined by Biology, Science, and Secondary Growths

Breast cancer was the first malignant tumor for which TNM classification was proposed by the International Union Against Cancer. Volume and distribution of tumor burden were considered clinically important in this cancer. Lung cancer is caused by excessive cigarette smoking. Prognosis is worst in small cell lung cancer and in non-small cell lung cancer measuring over 3 cm in size and having regional lymphatic spread. Metastatic spread from lung cancer is favored by lymphatic spread to the locoregional lymph nodes and blood-borne spread to 5 sites-lung, brain, bone, liver, and adrenal-all of which are unfavorable prognostic indicators.

Advances in radiotherapy in bone metastases in the context of new target therapies and ablative alternatives: A critical review

In patients with bone metastases (BM), radiotherapy (RT) is used to alleviate symptoms, reduce the risk of fracture, and improve quality of life (QoL). However, with the emergence of concepts like oligometastases, minimal invasive surgery, ablative therapies such as stereotactic ablative RT (SABR), radiosurgery (SRS), thermal ablation, and new systemic anticancer therapies, there have been a paradigm shift in the multidisciplinary approach to BM with the aim of preserving mobility and function survival. Despite guidelines on using single-dose RT in uncomplicated BM, its use remains relatively low. In uncomplicated BM, single-fraction RT produces similar overall and complete response rates to RT with multiple fractions, although it is associated with a higher retreatment rate of 20% versus 8%. Complicated BM can be characterised as the presence of impending or existing pathologic fracture, a major soft tissue component, existing spinal cord or cauda equina compression and neuropathic pain. The rate of complicated BM is around 35%. Unfortunately, there is a lack of prospective trials on RT in complicated BM and the best dose/fractionation regimen is not yet established. There are contradictory outcomes in studies reporting BM pain control rates and time to pain reduction when comparing SABR with Conventional RT. While some studies showed that SABR produces a faster reduction in pain and higher pain control rates than conventional RT, other studies did not show differences. Moreover, the local control rate for BM treated with SABR is higher than 80% in most studies, and the rate of grade 3 or 4 toxicity is very low. The use of SABR may be preferred in three circumstances: reirradiation, oligometastatic disease, and radioresistant tumours. Local ablative therapies like SABR can delay change or use of systemic therapy, preserve patients' Qol, and improve disease-free survival, progression-free survival and overall survival. Moreover, despite the potential benefit of SABR in oligometastatic disease, there is a need to establish the optial indication, RT dose fractionation, prognostic factors and optimal timing in combination with systemic therapies for SABR. This review evaluates the role of RT in BM considering these recent treatment advances. We consider the definition of complicated BM, use of single and multiple fractions RT for both complicated and uncomplicated BM, reirradiation, new treatment paradigms including local ablative treatments, oligometastatic disease, systemic therapy, physical activity and rehabilitation.

Stereotactic Body Radiotherapy for Patients with Lung Oligometastatic Disease: A Five-Year Systematic Review

For several years, oligometastatic disease has represented an intermediate state between localized disease accessible to local treatment and multimetastatic disease requiring systemic therapy. The lung represents one of the most common metastatic locations. Stereotactic body radiation therapy (SBRT) appears to be the treatment of choice for these patients. There are few data defining the place of radiotherapy and reporting outcome after SBRT in lung metastases. This 5-year review aimed to determine areas of SBRT usefulness and methods for the management of pulmonary metastasis in oligometastatic patients. A search for articles on PubMed allowed selection of the most relevant studies. Eighteen articles were selected according to pre-established criteria for this purpose. The analysis concludes that SBRT is an effective and safe treatment in selected patients when the disease remains localized from one to three organs.

Clinical impact of PET/MRI in oligometastatic colorectal cancer

BACKGROUND

Oligometastatic colorectal cancer (CRC) is potentially curable and demands individualised strategies.

METHODS

This single-centre retrospective study investigated if positron emission tomography (PET)/magnetic resonance imaging (MR) had a clinical impact on oligometastatic CRC relative to the standard of care imaging (SCI). Adult patients with oligometastatic CRC on SCI who also underwent PET/MR between 3/2016 and 3/2019 were included. The exclusion criterion was lack of confirmatory standard of reference, either surgical pathology, intraoperative gross confirmation or imaging follow-up. SCI consisted of contrast-enhanced (CE) computed tomography (CT) of the chest/abdomen/pelvis, abdominal/pelvic CE-MR, and/or CE whole-body PET/CT with diagnostic quality (i.e. standard radiation dose) CT. Follow-up was evaluated until 3/2020.

RESULTS

Thirty-one patients constituted the cohort, 16 (52%) male, median patient age was 53 years (interquartile range: 49-65 years). PET/MR and SCI results were divergent in 19% (95% CI 9-37%) of the cases, with PET/MR leading to management changes in all of them. The diagnostic accuracy of PET/MR was 90 ± 5%, versus 71 ± 8% for SCI. In a pairwise analysis, PET/MR outperformed SCI when compared to the reference standard (p = 0.0412).

CONCLUSIONS

These findings suggest the potential usefulness of PET/MR in the management of oligometastatic CRC.

Current Evidence for Stereotactic Body Radiotherapy in Lung Metastases

Lung metastases are the second most common malignant neoplasms of the lung. It is estimated that 20–54% of cancer patients have lung metastases at some point during their disease course, and at least 50% of cancer-related deaths occur at this stage. Lung metastases are widely accepted to be oligometastatic when five lesions or less occur separately in up to three organs. Stereotactic body radiation therapy (SBRT) is a noninvasive, safe, and effective treatment for metastatic lung disease in carefully selected patients. There is no current consensus on the ideal dose and fractionation for SBRT in lung metastases, and it is the subject of study in ongoing clinical trials, which examines different locations in the lung (central and peripheral). This review discusses current indications, fractionations, challenges, and technical requirements for lung SBRT.

Definitive radiotherapy for extracranial oligoprogressive metastatic renal cell carcinoma as a strategy to defer systemic therapy escalation

OBJECTIVE

To study whether delivering definitive radiotherapy (RT) to sites of oligoprogression in metastatic renal cell carcinoma (mRCC) enabled deferral of systemic therapy (ST) changes without compromising disease control or survival.

PATIENTS AND METHODS

We identified patients with mRCC who received RT to three or fewer sites of extracranial progressive disease between 2014 and 2019 at a large tertiary cancer centre. Inclusion criteria were: (1) controlled disease for ≥3 months before oligoprogression, (2) all oligoprogression sites treated with a biologically effective dose of ≥100 Gy, and (3) availability of follow-up imaging. Time-to-event end-points were calculated from the start of RT.

RESULTS

A total of 72 patients were identified (median follow-up 22 months, 95% confidence interval [CI] 19-32 months), with oligoprogressive lesions in lung/mediastinum (n = 35), spine (n = 30), and non-spine bone (n = 5). The most common systemic therapies before oligoprogression were none (n = 33), tyrosine kinase inhibitor (n = 23), and immunotherapy (n = 13). At 1 year, the local control rate was 96% (95% CI 87-99%); progression-free survival (PFS), 52% (95% CI 40-63%); and overall survival, 91% (95% CI 82-96%). At oligoprogression, ST was escalated (n = 16), maintained (n = 49), or discontinued (n = 7), with corresponding median (95% CI) PFS intervals of 19.7 (8.2-27.2) months, 10.1 (6.9-13.2) months, and 9.8 (2.4-28.9) months, respectively. Of the 49 patients maintained on the same ST at oligoprogression, 21 did not subsequently have ST escalation.

CONCLUSION

Patients with oligoprogressive mRCC treated with RT had comparable PFS regardless of ST strategy, suggesting that RT may be a viable approach for delaying ST escalation. Randomised controlled trials comparing treatment of oligoprogression with RT vs ST alone are needed.

Durvalumab Plus Tremelimumab in Solid Tumors: A Systematic Review

INTRODUCTION

Cancer immunotherapy represents one of the most important innovations in modern medicine. Durvalumab is an anti-programmed cell death ligand 1 (PDL-1) agent which is currently under investigation in several studies in combination with the anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) drug tremelimumab. The aim of this review was to systematically identify and revise the current scientific literature investigating the combination of these two drugs in solid tumors.

METHODS

A digital search on the Medline (PubMed interface) and Scopus databases for articles published from inception to 26 February 2021 was performed. The terms used for the search were durvalumab AND tremelimumab. Trials reported in English involving adult patients with solid cancers treated with the combination durvalumab plus tremelimumab were retrieved; the references of the articles were cross-checked to identify missing papers.

RESULTS

The electronic search produced 267 results; after exclusion of duplicates, irrelevant articles, reviews, and papers not in English or missing data, 19 articles were included for revision. The total number of patients treated with the combination of durvalumab and tremelimumab in the studies retrieved was 2052.

CONCLUSION

The combination of durvalumab plus tremelimumab showed some oncological advantages in comparison with traditional chemotherapies in some subsets of tumors, but generally has not shown consistent advantages in comparison with the employment of durvalumab monotherapy. A number of the studies examined had intrinsic methodological limitations; therefore, future well-designed studies involving larger cohorts are warranted.

Novel strategy to treat lung metastases: Hybrid therapy involving surgery and radiofrequency ablation

BACKGROUND

This study was performed to evaluate the clinical outcomes of hybrid treatment involving surgical resection and percutaneous radiofrequency ablation for patients with multiple lung metastases.

METHODS

Seventeen patients (6 men, 11 women; median age, 52 years; range, 16-78 years) underwent hybrid treatment involving surgery and radiofrequency ablation to treat multiple lung metastases (median number, 4; range, 2-26) between May 2014 and February 2020. The primary lesions were colorectal carcinoma (n = 9), uterine endometrial carcinoma (n = 3), osteosarcoma (n = 2), renal cell carcinoma (n = 1), glottic carcinoma (n = 1), and fibrolamellar hepatocellular carcinoma (n = 1). Twenty-four sessions each of surgery and radiofrequency ablation were performed. Safety, disease-free survival, and overall survival were evaluated. Safety was assessed according to the Clavien-Dindo Classification.

RESULTS

A grade IVa adverse event of empyema developed in one patient (4%, 1/24) after surgery. A grade IIIa adverse event of pneumothorax and a grade II adverse event of lung abscess occurred in four (17%, 4/24) and one session (4%, 1/24) after radiofrequency ablation, respectively. During the median follow up of 34 months (range, 8-67 months), 10 patients (59%, 10/17) developed new metastases. The 5-year disease-free survival rate was 32%. Four or fewer lung metastases (p = 0.008) and metastases from colorectal carcinoma (p = 0.02) were factors significantly associated with longer disease-free survival. One patient (6%, 1/17) died of tumor progression 29 months after initial treatment. The 5-year overall survival rate was 88%.

CONCLUSIONS

The strategy of hybrid treatment involving surgery and radiofrequency ablation may offer good outcomes for patients with multiple lung metastases.

Mature Experiences Using Local Therapy for Oligometastases

Cancer is a heterogeneous disease, consisting of a spectrum of disorders ranging from local-only disease to those that are widely metastatic from their onset. The oligometastatic state, in which tumors harbor a limited number of metastases, may be curable in a subset of patients. The early success of surgical resection of hepatic metastases from colorectal cancer led to investigations into metastatectomy of other sites and, more recently, into the use of stereotactic ablative radiotherapy (SABR) for oligometastatic disease. This article reviews the data establishing the role of surgery for managing limited metastatic disease. Further, we review recent experiences using alternative local therapies, such as SABR, for oligometastases. This review also discusses ongoing trials evaluating local therapies for patients with a limited burden of metastatic cancer.

Phase 3 Multi-Center, Prospective, Randomized Trial Comparing Single-Dose 24 Gy Radiation Therapy to a 3-Fraction SBRT Regimen in the Treatment of Oligometastatic Cancer

PURPOSE

This prospective phase 3 randomized trial was designed to test whether ultra high single-dose radiation therapy (24 Gy SDRT) improves local control of oligometastatic lesions compared to a standard hypofractionated stereotactic body radiation therapy regimen (3 × 9 Gy SBRT). The secondary endpoint was to assess the associated toxicity and the impact of ablation on clinical patterns of metastatic progression.

METHODS AND MATERIALS

Between November 2010 and September 2015, 117 patients with 154 oligometastatic lesions (≤5/patient) were randomized in a 1:1 ratio to receive 24 Gy SDRT or 3 × 9 Gy SBRT. Local control within the irradiated field and the state of metastatic spread were assessed by periodic whole-body positron emission tomography/computed tomography and/or magnetic resonance imaging. Median follow-up was 52 months.

RESULTS

A total of 59 patients with 77 lesions were randomized to 24 Gy SDRT and 58 patients with 77 lesions to 3 × 9 Gy SBRT. The cumulative incidence of local recurrence for SDRT-treated lesions was 2.7% (95% confidence interval [CI], 0%-6.5%) and 5.8% (95% CI, 0.2%-11.5%) at years 2 and 3, respectively, compared with 9.1% (95% CI, 2.6%-15.6%) and 22% (95% CI, 11.9%-32.1%) for SBRT-treated lesions (P = .0048). The 2- and 3-year cumulative incidences of distant metastatic progression in the SDRT patients were 5.3% (95% CI, 0%-11.1%), compared with 10.7% (95% CI, 2.5%-18.8%) and 22.5% (95% CI, 11.1%-33.9%), respectively, for the SBRT patients (P = .010). No differences in toxicity were observed.

CONCLUSIONS

The study confirms SDRT as a superior ablative treatment, indicating that effective ablation of oligometastatic lesions is associated with significant mitigation of distant metastatic progression.