Hypofractionated Stereotactic Radiotherapy for Non-breast or Prostate Cancer Oligometastases: A Tail of Survival Beyond 10 Years

Locoregional therapy for oligometastatic cervical cancer: a single-center retrospective study

BACKGROUND

Oligometastases are limited in number and extent, and therefore, are amenable to locoregional therapy.

OBJECTIVE

To analyze recurrence patterns, survival outcomes, and prognostic factors in patients with cervical cancer receiving locoregional therapy for oligometastases.

METHODS

The included patients had 1-3 extracranial oligometastases and received definitive radiotherapy, surgery, or ablation at a single institution between January 2007 and May 2022. Outcomes were evaluated using the Kaplan-Meier method. Prognostic factors were examined using the Cox proportional hazards model, and tumor growth rates were predicted by non-linear regression.

RESULTS

We identified 56 patients who presented with an oligometastatic disease to the supraclavicular fossa (n=19), lung (n=33), or other sites (n=4). Totals of 30 (53.6%), 41 (73.2%), 47 (83.9%), and 52 (92.9%) patients were diagnosed 1, 2, 3, and 4 years after cervical cancer diagnosis, respectively. Seven patients were simultaneously treated for para-aortic or pelvic recurrences. After a median follow-up of 24 months (range 1-86), the 3-year local recurrence-free rate in patients with supraclavicular versus non-supraclavicular oligometastases was 100% vs 93.5%. The 3-year overall survival rate was 40.1% vs 55.2% (p=0.04). Ten (17.9%) patients experienced new oligometastatic progression in a median of 8 months (range 4-14). Multivariate analysis showed that tumor size was the only prognostic factor for overall survival, with a 3-year overall survival rate of 91.7% vs 21.6% (≤15 mm vs >15 mm, p<0.001). Nineteen (86.4%) of 22 lesions diagnosed within 6 months of the last negative CT scan had a maximum diameter of ≤15 mm, and the predicted interval of tumor growth to 15 mm was 5.8 months.

CONCLUSION

Locoregional therapy for cervical cancer oligometastases can achieve long-term survival, especially in patients with small lesions (≤15 mm). Better follow-up mode after cervical cancer treatment and system therapy for oligometastases should be further explored.

Stereotactic body radiation therapy in the treatment of cancer patients with oligometastatic disease: a real world study

PURPOSE

Stereotactic body radiation therapy (SBRT) is a treatment modality with curative intent for oligometastatic cancer patients, commonly defined by a low-burden metastatic disease with 1-5 systemic metastases. Better knowledge of the clinical profile and prognostic factors in oligometastatic cancer patients could help to improve the selection of candidates who may obtain most benefits from SBRT. The objective of this study was to describe the clinical data and outcome in term of overall survival (OS) of patients with oligometastatic disease treated with SBRT over a 6-year period.

METHODS

From 2013 to 2018, 284 solid tumor cancer patients with 1-5 oligometastases underwent SBRT at a large university-affiliated oncological center in Barcelona, Spain. Variables related to the patient profile, tumor, oligometastatic disease, and treatment were evaluated.

RESULTS

A total of 327 metastatic tumors were treated with SBRT. In 65.5% of cases, metachronous tumors were diagnosed at least 1 year after diagnosis of the primary tumor. The median age of the patients was 73.9 years and 66.5% were males. The median follow-up was 37.5 months. The most common primary tumors were lung and colorectal cancer, with lung and bone as the most commonly treated metastatic sites. Ninety-three percent of patients showed a Karnofsky score (KPS) between 80 and 100. Adenocarcinoma was the most common histological type. The median overall survival was 53.4 months, with 1-, 2- and 5-year survival rates of 90.5%, 73.9% and 43.4%, respectively. Overall survival rates of breast (67.6 months, 95% CI 56.4-78.9), urological (63.3 months, 95% CI 55.8-70.8), and colorectal (50.8 months, 95% CI 44.2-57.4) tumors were higher as compared with other malignancies (20 months, 95% CI 11.2-28.8 months) (p < 0.001). Patients with Karnofsky score (KPS) of 90 and 100 showed a significantly better survival than those with impaired performance status (p = 0.001).

CONCLUSION

SBRT appears to be well tolerated and safe approach in oligometastatic patients. Patients with good performance status and with primary breast, urological and colorectal cancer have higher OS compared with other malignancies. More studies are necessary to evaluate the prognostic factors in oligometastatic disease (OMD) in order to select patients who could benefit more from this therapeutic approach.

Completeness of reporting oligometastatic disease characteristics in literature and influence on oligometastatic disease classification using the ESTRO/EORTC nomenclature

BACKGROUND

There is increasing evidence for the integration of locally ablative therapy into multimodality treatment of oligometastatic disease (OMD). To support standardised data collection, analysis, and comparison, a consensus OMD classification based on fundamental disease and treatment characteristics has previously been established. This study investigated the completeness of reporting the proposed OMD characteristics in literature and evaluated whether the proposed OMD classification system can be applied to the historical data.

METHODS

A systematic literature review was performed in Medline, Embase, and Cochrane, searching for prospective and retrospective studies, where SBRT was a treatment component of OMD. Reporting of the OMD characteristics as described in the EORTC/ESTRO classification was analyzed, feasibility to retrospectively classify the proposed OMD states was investigated and the impact of the categorisation on overall survival (OS) was evaluated.

RESULTS

Our study shows incomplete reporting of the proposed OMD characteristics. The most fully reported characteristic was 'type of involved organs' (88/95 studies); 'history of cancer progression' was the least reported (not mentioned in 50/95 studies). Retrospective OMD classification of existing literature was only possible for 7/95 studies. With respect to categorization as de novo, repeat or induced OMD, homogeneous patient cohorts were observed in 21/95 studies, most frequently de novo OMD, in 20 studies. Differences in OS at 2, 3, or 5 years were not statistically significant between the different states. OS was significantly influenced by primary tumor histology, with superior OS observed for prostate cancer and worst OS observed for non-small cell lung cancer.

CONCLUSION

The largely incomplete reporting of the proposed OMD characteristics hampers a retrospective classification of existing literature. To facilitate future comparison of individual studies, as well as validation of the OMD classification, comprehensive reporting of OMD characteristics using standardised terminology is recommended, as proposed by the EORTC/ESTRO classification system and following ESTRO-ASTRO consensus.

Safety, Efficacy, and Patterns of Failure After Single-Fraction Stereotactic Body Radiation Therapy (SBRT) for Oligometastases

Purpose

Fewer attendances for radiation therapy results in increased efficiency and less foot traffic within a radiation therapy department. We investigated outcomes after single-fraction (SF) stereotactic body radiation therapy (SBRT) in patients with oligometastatic disease.

Methods and Materials

Between February 2010 and June 2019, patients who received SF SBRT to 1 to 5 sites of oligometastatic disease were included in this retrospective study. The primary objective was to describe patterns of first failure after SBRT. Secondary objectives included overall survival (OS), progression-free survival (PFS), high-grade treatment-related toxicity (Common Terminology Criteria for Adverse Events grade ≥3), and freedom from systemic therapy (FFST).

Results

In total, 371 patients with 494 extracranial oligometastases received SF SBRT ranging from 16 Gy to 28 Gy. The most common primary malignancies were prostate (n = 107), lung (n = 63), kidney (n = 52), gastrointestinal (n = 51), and breast cancers (n = 42). The median follow-up was 3.1 years. The 1-, 3-, and 5-year OS was 93%, 69%, and 55%, respectively; PFS was 48%, 19%, and 14%, respectively; and FFST was 70%, 43%, and 35%, respectively. Twelve patients (3%) developed grade 3 to 4 treatment-related toxicity, with no grade 5 toxicity. As the first site of failure, the cumulative incidence of local failure (irrespective of other failures) at 1, 3 and 5 years was 4%, 8%, and 8%, respectively; locoregional relapse at the primary was 10%, 18%, and 18%, respectively; and distant failure was 45%, 66%, and 70%, respectively.

Conclusions

SF SBRT is safe and effective, and a significant proportion of patients remain FFST for several years after therapy. This approach could be considered in resource-constrained or bundled-payment environments. Locoregional failure of the primary site is the second most common pattern of failure, suggesting a role for optimization of primary control during metastasis-directed therapy.

The Role of Local Treatment in Oligometastatic and Oligoprogressive Cancer

BACKGROUND

Systemic treatment is standard for most types of cancer with disseminated metastases. The role of local treatment (LT) of individual tumor foci in patients with oligometastatic disease is unclear and the object of current scientific studies.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed.

RESULTS

Four randomized trials have shown that radical local treatment confers an advantage with respect to overall survival (OS), compared to systemic treatment alone, in patients with oligometastatic disease. In patients with synchronous metastases and a stable primary tumor, LT prolongs the median overall survival by approximately two years. A single randomized trial for oligometastatic small-cell lung cancer did not show any prolongation of overall survival. Local treatment increased the frequency of grade III side effects by approximately 10%.

CONCLUSION

Although local treatment already has a place in many guidelines on the basis of the findings of a small number of prospective and retrospective studies, a option of local treatment should be considered by an interdisciplinary tumor board individually for suitable patients.