Oligometastases revisited

Osseous oligometastases from thymic carcinoma: a case report suggesting the effectiveness of palliative-intent radiotherapy treatment

Background

Oligometastasis, a recently proposed concept, is defined as an intermediate state of cancer, between localized and systemic disease, that may be well controlled by local ablative treatment. Thymic carcinoma is a rare cancer with a poor prognosis. A definitive management approach has yet to be confirmed by a high level of evidence.

Case presentation

We present the case of a 41-year-old female who underwent curative-intent surgery for a stage III squamous cell carcinoma of the thymus. Bone metastases were detected 1 year later by magnetic resonance imaging. These were treated with palliative-intent radiotherapy. Disease progression has not been observed in more than 15 years since the achievement of complete radiological remission.

Conclusion

The treatment outcomes in this and other reported cases suggest that some patients with oligometastatic thymic carcinoma may achieve prolonged survival or even cure with low-dose radiotherapy delivered to the metastases.

Radiotherapy Combined With Androgen Deprivation for Bone Oligometastases After Primary Curative Radiotherapy for Prostate Cancer: A Retrospective Study

To evaluate the effects and toxicity of radiotherapy (RT) combined with androgen deprivation (AD) for bone oligometastases after primary curative RT for prostate cancer (PCa).We retrospectively analyzed 30 consecutively treated PCa patients with bone oligometastases from April 2005 to July 2014. All patients underwent RT combined with AD for oligometastatic bones after curative RT for PCa. Measured outcomes included overall survival (OS) rate, local control (LC), progression-free survival (PFS), pain relief, and toxicities. Statistical analysis was performed with SPSS17.0.The median follow-up was 32.5 months (range, 0.6-50.3). The 3-year PFS and OS rates were 22.8% (95% CI, 13.4-37.5%) and 69% (95% CI, 51.7-81.1%), respectively. The number of bone oligometastases and RT schedule were found to be significantly associated with OS on univariate analysis (P < 0.05, respectively). The 3-year OS for patients with 1 and >1 metastases was 78.8% versus 42.2%, respectively (P = 0.037). The long-course RT was associated with better 3-year OS compared with short-course (76.4% vs 44.1%, P = 0.03). A total of 15 (83.3%, 15/18) patients achieved pain relief. No grade 3 toxicity was observed.Long-course RT combined with ADT was effective and well-tolerated in PCa patients with bone oligometastases after curative RT for PCa. Further randomized controlled trials are needed to corroborate the findings.

14q32-encoded microRNAs mediate an oligometastatic phenotype

Oligometastasis is a clinically distinct subset of metastasis characterized by a limited number of metastases potentially curable with localized therapies. We analyzed pathways targeted by microRNAs over-expressed in clinical oligometastasis samples and identified suppression of cellular adhesion, invasion, and motility pathways in association with the oligometastatic phenotype. We identified miR-127-5p, miR-544a, and miR-655-3p encoded in the 14q32 microRNA cluster as co-regulators of multiple metastatic pathways through repression of shared target genes. These microRNAs suppressed cellular adhesion and invasion and inhibited metastasis development in an animal model of breast cancer lung colonization. Target genes, including TGFBR2 and ROCK2, were key mediators of these effects. Understanding the role of microRNAs expressed in oligometastases may lead to improved identification of and interventions for patients with curable metastatic disease, as well as an improved understanding of the molecular basis of this unique clinical entity.

Approach to Oligometastatic Prostate Cancer

Oligometastatic prostate cancer has increasingly been recognized as a unique clinical state with therapeutic implications. It has been proposed that patients with oligometastases may have a more indolent course and that outcome may be further improved with metastasis-directed local ablative therapy. In addition, there are differing schools of thoughts regarding whether oligometastases represent isolated lesions-where targeted therapy may render a patient disease free-or whether they coexist with micrometastases, where targeted therapy in addition to systemic therapy is required for maximal clinical impact. As such, the approach to the patient with oligometastatic prostate cancer requires multidisciplinary consideration, with surgery, radiotherapy, and systemic therapy potentially of benefit either singularly or in combination. Indeed, mounting evidence suggests durable disease-free intervals and, in some cases, possibly cure, may be achieved with such a multimodal strategy. However, selecting patients that may benefit most from treatment of oligometastases is an ongoing challenge. Moreover, with the advent of new, highly sensitive imaging technologies, the spectrum based on CT of the abdomen and pelvis and technetium bone scan of localized to oligometastatic to widespread disease has become increasingly blurred. As such, new MRI- and PET-based modalities require validation. As some clinical guidelines advise against routine prostate-specific antigen screening, the possibility of more men presenting with locally advanced or de novo oligometastatic prostate cancer exists; thus, knowing how best to treat these patients may become more relevant at a population level. Ultimately, the arrival of prospective clinical data and better understanding of biology will hopefully further inform how best to treat men with this disease.

Stereotactic body radiotherapy (SBRT) with or without surgery for primary and metastatic liver tumors

OBJECTIVES

We report single center experience on the outcome and toxicity of SBRT alone or in combination with surgery for inoperable primary and metastatic liver tumors between 2007 and 2014.

PATIENTS AND METHODS

Patients with 1-4 hepatic lesions and tumor diameter ≤9 cm received SBRT at 46.8Gy ± 3.7 in 4-6 fractions. The primary end point was local control with at least 6 months of radiographic followup, and secondary end points were toxicity and survival.

RESULTS

Eighty-seven assessable patients (114 lesions) completed liver SBRT for hepatoma (39) or isolated metastases (48) with a median followup of 20.3 months (range 1.9-64.1). Fourteen patients underwent liver transplant with SBRT as a bridging treatment or for tumor downsizing. Eight patients completed hepatic resections in combination with planned SBRT for unresectable tumors. Two-year local control was 96% for hepatoma and 93.8% for metastases; it was 100% for lesions ≤4 cm. Two-year overall survival was 82.3% (hepatoma) and 64.3% (metastases). No incidence of grade >2 treatment toxicity was observed.

CONCLUSION

In this retrospective analysis we demonstrate that liver SBRT alone or in combination with surgery is safe and effective for the treatment of isolated inoperable hepatic malignancies and provides excellent local control rates.

Evaluation of response after SBRT for liver tumors

Stereotactic body radiotherapy (SBRT) has developed over the last few years for the treatment of primary and metastatic hepatic tumors. The tumoral and adjacent peritumoral modifications caused by this radiosurgery limit the evaluation of response by anatomic imaging and dimensional criteria alone, such as with RECIST. This suggests that it is of interest to also take into account the residual enhancement and hyper metabolism of these hepatic targets. We have reviewed the English language literature regarding the response of hepatic lesions treated by SBRT, and found that only seven articles were specifically concerned with this problem. The response of the hepatocellular carcinoma after SBRT has been studied specifically with multiphase enhanced CT-scan. Criteria set by the European Association of Study of the Liver better estimate response at each time point of follow up than RECIST does. Non-enhancement, reflecting tumor necrosis, is additionally an early indicator of response with extended response in time and a best non-enhancement percentage is observed at 12 months. The response after treatment by SBRT of cholangiocarcinoma has not yet generated a specific report. Use of RECIST criteria is also inadequate in the evaluation of response after SBRT for hepatic metastases. Response of liver metastases to SBRT is better assessed with a combination of size and enhancement pattern. The occurrence of a lobulated enhancement during follow up is efficient to predict local progression in a specific, reproducible, and sensitive way. Patients with FDG-avid hepatic metastases are also better evaluated with PET-CT and functional criteria than routine imaging and metric evaluation alone.

Surgical management and minimally invasive approaches for the treatment of metastatic sarcoma

Soft tissue sarcomas describe a very heterogeneous group of soft tissue tumors mainly arising in the lower extremities. If diagnosed at an early stage and a complete resection of the primary tumor is achieved, the patients' prognosis is excellent. However, metastatic tumor spread is common with only limited treatment possibilities. Despite an improved insight into tumor biology of sarcomas, no notable improvement has been gained in the last 20 years regarding prognosis of patients. Metastatic lung disease has long been the preserve of systemic treatments, local treatments being considered in a purely palliative intention. Several studies have objectified benefit to the local treatment of metastases, especially in an oligometastatic state. The development of techniques for stereotactic radiotherapy on the one hand and the refusal or contraindication for surgery on the other hand inaugurated studies in this direction. Besides surgery and radiotherapy, other local modalities have been investigated in the last few years such as thermal therapy (radiofrequency and laser ablation) or combined modalities (isolated limb perfusion and deep-wave hyperthermia plus chemotherapy) to help patients with metastatic soft tissue sarcoma. Minimally invasive, image-guided therapies such as thermal ablation should be considered particularly in patients who are not suitable surgical candidates or may have exhausted all other viable surgical options. Some of these techniques will be reviewed in this article, and their value for the patients will be evaluated in the light of indication from tumor biology and technical feasibility. These highly selected and specific procedures should only be performed after decision making in an interdisciplinary sarcoma-board.

The role of stereotactic ablative radiotherapy (SBRT) in the management of oligometastatic non small cell lung cancer

Our understanding of metastatic disease has evolved significantly in the last 20 years. Considered strictly a systemic issue, local treatment would only have significant impact in terms of palliation. However, Hellman and Weichselbaum stated that there might be an intermediate state, in which controlling limited metastatic sites could improve oncologic outcomes. This is called an oligometastatic state, a point between locally confined cancer and widespread disease [1,2]. As treatment with chemotherapy alone for non small cell lung cancer (NSCLC) yields median survivals of 8-11 months [3] and minimal chances of long term survival, new strategies are needed to offer better odds for metastatic patients. Outcomes tend to be better in patients with low volume metastatic disease. [4,5], leading us to question whether the oligometastatic group of patients will gain from a more radical treatment paradigm. In this setting, ablative treatments like surgery or SBRT may provide longer survival and better local control times. There is a rationale for the use of ablative local treatments, as most failures after chemotherapy occur at sites initially affected by disease, and these sites could be a source of further dissemination. Also, chemotherapy resistance can adversely impact resolution of metastatic disease [6]. In rare cases, the abscopal effect (an immune effect arising after radiotherapy in non irradiated metastatic sites) has been described [7,8]. In this review article, we address the impact of SBRT in oligometastatic NSCLC, the most relevant prognostic factors, indications and a site specific review. This review will focus on SBRT for extracranial disease as the role for intracranial SBRT is established.

Radiotherapy for isolated lymph node metastases in patients with locally advanced prostate cancer after primary therapy

PURPOSE

To evaluate the outcome of radiotherapy for isolated lymph node metastases in patients with progression towards castration-resistant prostate cancer (CRPC) after definitive therapy.

METHODS

Between 11/2009 and 06/2014, 18 patients with isolated lymph node metastases after definitive prostate cancer therapy received radiotherapy to the affected lymph nodes with a total dose of 50.4 or 54.0 Gray (Gy). All patients had continuously rising levels of PSA despite androgen deprivation therapy (ADT). Biochemical progression-free survival (BPFS), clinical failure-free survival (CFFS) and freedom from local failure were assessed, as was the toxicity profile.

RESULTS

Of the 18 patients, 17 had high-risk prostate cancer. Radiotherapy was performed at a median interval of 64.55 [interquartile range (IQR) 23.2-153.8] months after definitive therapy. ADT was administered for a median (IQR) time of 3.8 (3.2-24.7) months prior to irradiation. The median (IQR) follow-up was 15.59 (5.3-28.5) months with 94.1 % freedom from local failure. The median BPFS and CFFS were 5.85 (IQR 3.0-20.3) and 9.60 months (IQR 5.9-28.8), respectively. No grade III acute or grade II late toxicity was observed. Only two patients developed local relapse. No patients exhibited deterioration of urinary or faecal continence.

CONCLUSION

Radiotherapy of isolated lymph node metastases in patients who develop CRPC provides effective local control, is not associated with clinically important acute or long-term side effects, improves PSA kinetics and may delay the necessity of chemotherapy.

Liver metastases and SBRT: A new paradigm?

BACKGROUND

The outstanding innovations made by early diagnosis, novel surgical techniques, effective chemotherapy regimens and conformal radiotherapy, have significantly improved patients overall survival and quality of life. Multidisciplinary approach to cancer has also led to an increased prevalence of patients with few, organ-confined metastases, who can experience long-term survival even if their disease is no longer localized. Liver is one of the most common site for metastatic disease from several cancers, and when metastatic disease is confined to liver, given the ability of this organ to regenerate almost to its optimal volume, surgical resection represents the standard of care because is associated with a better prognosis. Approximately 70-90% of liver metastases, however, are unresectable and a safe, effective alternative therapeutic option is necessary for these patients.

MATERIALS AND METHODS

A review of the current literature was performed to analyze the role of SBRT in treating liver metastases from different cancers. A literature search using the terms "SBRT" and "liver metastases" was carried out in PUBMED.

RESULTS

Stereotactic body radiation therapy has shown to provide promising results in the treatment of liver metastases, thanks to the ability of this procedure to deliver a conformal high dose of radiation to the target lesion and a minimal dose to surrounding critical tissues.

CONCLUSION

Stereotactic body radiation therapy is a non-invasive, well-tolerated and effective treatment for patients with liver metastases not suitable for surgical resection.

Synchronous Oligometastatic Non-Small Cell Lung Cancer and Isolated Renal Cell Carcinoma: A Case Report and Literature Review

A 58-year-old gentleman presenting with a progressive headache, visual disturbance, decreased appetite, and weight loss was found to have a localized clear cell carcinoma of the kidney and synchronous Stage IV non-small cell lung cancer with a solitary brain metastasis. This case illustrates the challenges in distinguishing between primary and metastatic disease in a patient with both renal cell carcinoma and lung cancer. We highlight the uncertainties in the diagnosis and management of this unique clinical scenario and the potential implications on prognosis.

Long-term safety and efficacy of stereotactic body radiation therapy for hepatic oligometastases

PURPOSE

To evaluate long-term outcome and toxicity of stereotactic body radiation therapy (SBRT) for hepatic oligometastases from solid tumors.

METHODS AND MATERIALS

Eligible patients had 1 to 3 liver metastases, maximum sum diameter 6 cm, without extrahepatic progression. We treated 106 lesions in 81 patients; 67% with colorectal primaries. Median dose was 5400 cGy in 3 to 5 fractions.

RESULTS

At median follow-up of 33 months (2.5-70 months), overall local control was 94% (95% confidence interval, not estimable); Kaplan-Meier estimated 96% at 1 year and 91% at 2, 3, and 4 years. Partial/complete response was observed in 69% of lesions with less than 3% progressing. Median survival time was 33.6 months (95% confidence interval, 29.1-38.4); Kaplan-Meier survival estimates at 1, 2, 3, and 4 years were 89.9%, 68.6%, 44.0%, and 28.0%, respectively. Grade 3 or greater liver toxicity was 4.9%.

CONCLUSION

SBRT is effective for selected patients with hepatic oligometastases with limited toxicities. A phase 3 trial comparing SBRT with "gold-standard" surgical resection is warranted.

Stereotactic ablative radiotherapy for pulmonary oligometastases and oligometastatic lung cancer

An increasing body of experience suggests that oligometastasis represents a minimal metastatic state with the potential for cure or prolonged survival in selected patients treated with radical local therapy to all identified sites of disease. The main clinical scenarios managed by thoracic oncology specialists are pulmonary oligometastases from primary malignancies of other anatomic sites and primary lung cancer with oligometastases to lung or other organs. Surgery has been a mainstay of treatment in these situations, with remarkably favorable outcomes following pulmonary metastasectomy in well-selected patient cohorts. As with early stage lung cancer in patients who are medically inoperable, stereotactic ablative radiotherapy is emerging as a prominent local treatment option for oligometastatic disease. We review the role and clinical experience of stereotactic ablative radiotherapy for pulmonary oligometastases and oligometastatic lung cancer.

"Hit the primary": A paradigm shift in the treatment of metastatic prostate cancer?

Patients with metastatic prostate cancer (PC) represent a heterogeneous group with survival rates varying between 13 and 75 months. The current standard treatment in this setting is hormonal therapy, with or without docetaxel-based chemotherapy. In the era of individualized medicine, however, maximizing treatment options, especially in long-term surviving patients with limited disease burden, is of capital importance. Emerging data, mainly from retrospective surgical series, show survival benefits in men diagnosed with metastatic PC following definitive therapy for the prostate. Whether the irradiation of primary tumor in a metastatic disease might improve the therapeutic ratio in association with systemic treatments remains investigational. In this scenario, modern radiation therapy (RT) can play a significant role owing to its intrinsic capability to act as a more general immune response modifier, as well as to the potentially better toxicity profile compared to surgery. Preclinical data, clinical experience, and challenges in local treatment in de novo metastatic PC are reviewed and discussed.

Extending the Frontiers Beyond Thermal Ablation by Radiofrequency Ablation: SBRT, Brachytherapy, SIRT (Radioembolization)

Metastatic spread of the primary is still defined as the systemic stage of disease in treatment guidelines for various solid tumors. This definition is the rationale for systemic therapy. Interestingly and despite the concept of systemic involvement, surgical resection as a local treatment has proven to yield long-term outcomes in a subset of patients with limited metastatic disease, supporting the concept of oligometastatic disease. Radiofrequency ablation has yielded favorable outcomes in patients with hepatocellular carcinoma and colorectal metastases, and some studies indicate its prognostic potential in combined treatments with systemic therapies. However, some significant technical limitations apply, such as size limitation, heat sink effects, and unpredictable heat distribution to adjacent risk structures. Interventional and non-invasive radiotherapeutic techniques may overcome these limitations, expanding the options for oligometastatic patients and cytoreductive concepts. Current data suggest very high local control rates even in large tumors at any given location in the human body. The article focusses on the characteristics and possibilities of stereotactic body radiation therapy, interstitial high-dose-rate brachytherapy, and Yttrium-90 radioembolization. In this article, we discuss the differences of the technical preferences as well as their impact on indications. Current data is presented and discussed with a focus on application in oligometastatic or cytoreductive concepts in different tumor biologies.

Near infrared photoimmunotherapy prevents lung cancer metastases in a murine model

Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of intravenously injected antibodies with the acute toxicity induced by photosensitizers after exposure to NIR-light. Herein, we evaluate the efficacy of NIR-PIT in preventing lung metastases in a mouse model. Lung is one of the most common sites for developing metastases, but it also has the deepest tissue light penetration. Thus, lung is the ideal site for treating early metastases by using a light-based strategy. In vitro NIR-PIT cytotoxicity was assessed with dead cell staining, luciferase activity, and a decrease in cytoplasmic GFP fluorescence in 3T3/HER2-luc-GFP cells incubated with an anti-HER2 antibody photosensitizer conjugate. Cell-specific killing was demonstrated in mixed 2D/3D cell cultures of 3T3/HER2-luc-GFP (target) and 3T3-RFP (non-target) cells. In vivo NIR-PIT was performed in the left lung in a mouse model of lung metastases, and the number of metastasis nodules, tumor fluorescence, and luciferase activity were all evaluated. All three evaluations demonstrated that the NIR-PIT-treated lung had significant reductions in metastatic disease (*p < 0.0001, Mann-Whitney U-test) and that NIR-PIT did not damage non-target tumors or normal lung tissue. Thus, NIR-PIT can specifically prevent early metastases and is a promising anti-metastatic therapy.

Surgery of the primary tumor in de novo metastatic breast cancer: To do or not to do?

Approximately five percent of all breast cancer patients in developed countries present with distant metastases at initial diagnosis. Due to its incurability, metastatic breast cancer is generally treated with systemic therapies to achieve disease control and reduce tumor-related symptoms. Primary treatments for metastatic breast cancer are chemotherapy, endocrine- and biologic therapy, whereas surgery with or without radiotherapy is usually performed to treat impending wound issues. Since 2002, several retrospective non-randomized clinical studies have shown that extirpation of the primary tumor correlates with a significantly improved survival in patients with primary metastatic breast cancer. Others have argued that this survival benefit associated with surgery may be due to selection biases. Therefore, in the absence of published results from randomized controlled trials carried out in India and Turkey and completion of a trial in the United States, there is no clear conclusion on whether surgical excision of the primary breast cancer translates into a survival benefit for patients with de novo metastatic disease. Furthermore, timing and type of surgical procedure, as well as selection of patients who could benefit the most from this approach, represent additional points of uncertainty. Despite the epidemiological burden of this condition, there are no guidelines on how to manage breast cancer patients presenting with de novo metastatic breast cancer; and decisions are often left to provider and patient preferences. Here, we present a critical overview of the literature focusing on the rationale and potential role of primary tumour excision in patients with de novo metastatic breast cancer.

Postoperative oligo-recurrence of non-small-cell lung cancer: clinical features and survival†

OBJECTIVES

Postoperative recurrences of non-small-cell lung cancer (NSCLC) are usually disseminated and systemic. Recently, the concept of oligo-recurrence, which is theoretically curable by definitive local therapy (DLT), has been proposed in several cancers. The aim of this study was to clarify clinical features and outcomes of patients with postoperative oligo-recurrence of NSCLC.

METHODS

From 3275 patients with resected pathological stage IA-IIIB NSCLC between 1993 and 2011, a total of 768 patients who developed recurrence were included in this study. Oligo-recurrence was defined as 1-3 loco-regional or distant recurrent lesions restricted to a single organ. Other recurrences were classified as poly-recurrence. Second primary lung cancers and suspected lesions were excluded. DLT included surgery, stereotactic radiotherapy and radiotherapy with a 45 Gy or higher dose, performed with curative intent.

RESULTS

Oligo-recurrence was identified in 162 (21%) patients, mainly as a solitary recurrence (n = 129, 80%) in regional lymph nodes, brain, lung, bone and adrenal gland, and the proportion of patients with oligo-recurrence increased gradually year by year. The patients with oligo-recurrence had more early-staged disease at initial surgery and a longer time to recurrence than those with poly-recurrence. The entire population of oligo-recurrence patients had better post-recurrence survival (PRS) than those with poly-recurrence (5-year PRS: 32.9 vs 9.9%, P < 0.001). For oligo-recurrence, DLT was totally conducted in 105 (65%) patients as initial treatment. Multivariate analyses revealed that the initial DLT was associated with improved PRS [odds ratio (OR) 0.44; 95% confidence interval (CI) 0.29-0.68]. The recurrence location and initial pathological stage did not affect PRS. The 5-year PRS and postoperative progression-free survival rates after DLT were 38.6 and 22.3%, respectively. Of the 10 long-term (≥5-year) progression-free survivors, 9 were those with a solitary recurrence.

CONCLUSIONS

Initial DLT for oligo-recurrence achieved favourable PRS in a selected population. Oligo-recurrence curable by DLT was found in a subset of patients who received DLT, mostly as a solitary recurrence.

Locally ablative treatment of breast cancer liver metastases: identification of factors influencing survival (the Mammary Cancer Microtherapy and Interventional Approaches (MAMMA MIA) study)

BACKGROUND

Liver metastases from breast cancer (LMBC) are typically considered to indicate systemic disease spread and patients are most often offered systemic palliative treatment only. However, retrospective studies suggest that some patients may have improved survival with local treatment of their liver metastases compared to systemic therapy alone. In the absence of randomized trials, it is important to identify patient characteristics indicating that benefit from local treatment can be expected.

METHODS

59 patients undergoing radiofrequency ablation (RFA), interstitial brachytherapy (BT), or radioembolization (RE) of LMBC as a salvage treatment were studied. Potential factors influencing survival were analyzed in a multivariate Cox model. For factors identified to have an independent survival impact, Kaplan-Meier analysis and comparison of overall survival (OS) using the log-rank test was performed.

RESULTS

Median OS following local interventional treatment was 21.9 months. Considering only factors evaluable at treatment initiation, maximum diameter of liver metastases (≥3.9 cm; HR: 3.1), liver volume (≥ 1376 mL; HR: 2.3), and history of prior chemotherapy (≥ 3 lines of treatment; HR: 2.5-2.6) showed an independent survival impact. When follow-up data were included in the analysis, significant factors were maximum diameter of liver metastases (≥ 3.9 cm; HR: 3.1), control of LMBC during follow-up (HR: 0.29), and objective response as best overall response (HR: 0.21). Neither the presence of any extrahepatic metastases nor presence of bone metastases only had a significant survival impact. Median OS was 38.7 vs. 16.1 months in patients with metastases < vs. ≥ 3.9 cm, 36.6 vs. 10.2 months for patients having objective response vs. stable/progressive disease, and 38.5 vs. 14.2 months for patients having controlled vs. non-controlled disease at follow-up.

CONCLUSION

Local control of LMBC confers a survival benefit and local interventional treatment for LMBC should be studied in a randomized trial. Patients with small metastases and limited history of systemic LMBC treatment are most likely to benefit from local approaches. Limited extrahepatic disease should not lead to exclusion from a randomized study and should not be a contraindication for local LMBC treatment as long as no randomized data are available.

Update on treatment of liver metastases: focus on ablation therapies

There is substantial and growing interest in the use of local therapies to treat patients with metastatic cancer, especially those deemed to have "oligometastatic" disease. Much of the literature to date consists of reports on metastasectomy for liver and lung metastases. Non-surgical minimally or non-invasive treatments including thermal ablation, irreversible electroporation, and high-dose radiation therapy (stereotactic ablative radiation therapy) can also be used in the treatment of primary and secondary tumors, including in the treatment of liver metastases. In this review, we discuss the rationale for using these ablative treatments in the treatment of liver metastases including similarities and differences between them.

Integrating Chemotherapy into the Management of Oligometastatic Colorectal Cancer: Evidence-Based Approach Using Clinical Trial Findings

BACKGROUND

This study used case reports to review the role of systemic chemotherapy in oligometastatic colorectal cancer (CRC) and to suggest ways to integrate clinical research findings into the interdisciplinary management of this potentially curable subset of patients.

METHODS

This educational review discusses the role of chemotherapy in the management of oligometastatic metastatic CRC.

RESULTS

In initially resectable oligometastatic CRC, the goal of chemotherapy is to eradicate micrometastatic disease. Perioperative 5-fluorouracil and oxaliplatin together with surgical resection can result in 5-year survival rates as high as 57 %. With the development of increasingly successful chemotherapy regimens, attention is being paid to chemotherapy used to convert patients with initially unresectable metastasis to patients with a chance of surgical cure. The choice of chemotherapy regimen requires consideration of the goals for therapy and assessment of both tumor- and patient-specific factors.

CONCLUSION

This report discusses the choice and timing of chemotherapy in patients with initially resectable and borderline resectable metastatic CRC. Coordinated multidisciplinary care of such patients can optimize survival outcomes and result in cure for patients with this otherwise lethal disease.

Phase I trial of everolimus in combination with thoracic radiotherapy in non-small-cell lung cancer

BACKGROUND

This phase I study evaluated the safety and efficacy of the oral mTOR inhibitor everolimus in combination with thoracic radiotherapy followed by consolidation chemotherapy in locally advanced or oligometastatic untreated non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Everolimus dose was escalated in incremental steps [sequential cohorts of three patients until the occurrence of dose-limiting toxicity (DLT)] and administered orally weekly (weekly group: dose of 10, 20 or 50 mg) or daily (daily group: 2.5, 5 or 10 mg), 1 week before, and during radiotherapy until 3.5 weeks after the end of radiotherapy. Two cycles of chemotherapy (cisplatin-navelbine) were administrated 4.5 weeks after the end of radiotherapy.

RESULTS

Twenty-six patients were included in two centers, 56% had adenocarcinoma and 84% had stage III disease. In the weekly group (12 assessable patients), everolimus could be administered safely up to the maximum planned weekly dose of 50 mg; however, one patient experienced a DLT of interstitial pneumonitis at the weekly dose level of 20 mg. In the daily group (9 assessable patients): one DLT of interstitial pneumonitis with a fatal outcome was observed at the daily dose level of 2.5 mg; two other DLTs (one grade 3 esophagitis and one bilateral interstitial pneumonitis) were found at the daily dose level of 5 mg. Overall there were five patients with G3-4 interstitial pneumonitis related to treatment. Among 22 assessable patients for response, there were 9 (41%) partial response and 7 (32%) stable disease. At a median follow-up of 29 months, the 2-year overall survival and progression-free survival actuarial rates were 31% and 12%, respectively.

CONCLUSION

In previously untreated and unselected NSCLC patients, the recommended phase II dose of everolimus in combination with thoracic radiotherapy is 50 mg/week. Pulmonary toxicity is of concern and should be carefully monitored to establish the potential role of mTOR inhibitor with concomitant radiotherapy.

EUDRACT N

2007-001698-27.

Near infrared photoimmunotherapy for lung metastases

Lung metastases are a leading cause of cancer related deaths; nonetheless current treatments are limited. Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of intravenously injected antibodies that target tumors with the toxicity induced by photosensitizers activated by NIR-light. Herein, we demonstrate the efficacy of NIR-PIT in a mouse model of lung metastases. Experiments were conducted with a HER2, luciferase and GFP expressing cell line (3T3/HER2-luc-GFP). An antibody-photosensitizer conjugate (APC) consisting of trastuzumab and a phthalocyanine dye, IRDye700DX, was synthesized. In vitro NIR-PIT-induced cytotoxicity was light dose dependent. With 3D culture, repeated NIR-PIT could eradicate entire spheroids. In vivo anti-tumor effects of NIR-PIT included significant reductions in both tumor volume (p = 0.0141 vs. APC) and bioluminescence image (BLI) (p = 0.0086 vs. APC) in the flank model, and prolonged survival (p < 0.0001). BLI demonstrated a significant reduction in lung metastases volume (p = 0.0117 vs. APC). Multiple NIR-PIT doses significantly prolonged survival in the lung metastasis model (p < 0.0001). These results suggested that NIR-PIT is a potential new therapy for the local control of lung metastases.

Predictors for long-term survival free from whole brain radiation therapy in patients treated with radiosurgery for limited brain metastases

Purpose

To identify predictors for prolonged survival free from salvage whole brain radiation therapy (WBRT) in patients with brain metastases treated with stereotactic radiosurgery (SRS) as their initial radiotherapy approach.

Materials and methods

Patients with brain metastases treated with SRS from 2001 to 2013 at our institution were identified. SRS without WBRT was typically offered to patients with 1–4 brain metastases, Karnofsky performance status ≥70, and life expectancy ≥3 months. Three hundred and eight patients met inclusion criteria for analysis. Medical records were reviewed for patient, disease, and treatment information. Two comparison groups were identified: those with ≥1-year WBRT-free survival (N = 104), and those who died or required salvage WBRT within 3 months of SRS (N = 56). Differences between these groups were assessed by univariate and multivariate analyses.

Results

Median survival for all patients was 11 months. Among patients with ≥1-year WBRT-free survival, median survival was 33 months (12–107 months) with only 21% requiring salvage WBRT. Factors significantly associated with prolonged WBRT-free survival on univariate analysis (p < 0.05) included younger age, asymptomatic presentation, RTOG RPA class I, fewer brain metastases, surgical resection, breast primary, new or controlled primary, absence of extracranial metastatic disease, and oligometastatic disease burden (≤5 metastatic lesions). After controlling for covariates, asymptomatic presentation, breast primary, single brain metastasis, absence of extracranial metastases, and oligometastatic disease burden remained independent predictors for favorable WBRT-free survival.

Conclusion

A subset of patients with brain metastases can achieve long-term survival after upfront SRS without the need for salvage WBRT. Predictors identified in this study can help select patients that might benefit most from a treatment strategy of SRS alone.

SABR for aggressive local therapy of metastatic cancer: A new paradigm for metastatic non-small cell lung cancer

Metastectomy has been performed for many years in situations where the functional consequences allow it, for example in the liver, lung, adrenal glands, and ovaries. This history suggests that selected patients may benefit from aggressive treatment of metastases. Technological developments now allow for ablative treatment of other tumor sites and perhaps for larger volume and/or increasing multiplicity of disease using Stereotactic Ablative Radiation Therapy (SABR) with relatively lower risk of morbidity to patients. Here we further explore the concept of aggressive local treatment of metastatic disease in adult patients and review the rationale for use of SABR to treat metastases and highlight new data supporting this approach in metastatic Non-Small Cell Lung Cancer.

SBRT: An Opportunity to Improve Quality of Life for Oligometastatic Prostate Cancer

Objective

Oligometastatic prostate cancer is a limited metastatic disease state in which potential long-term control is still possible with the use of targeted therapies such as surgery or stereotactic body radiation therapy (SBRT). SBRT may as well potentially prolong the time before the initiation of androgen deprivation therapy (ADT) and docetaxel chemotherapy for oligometastatic prostate cancer. The goal of this study is to outline prognostic factors associated with improved outcome with SBRT for metastatic prostate cancer and to quantify the effect of prior systemic treatments such as ADT and docetaxel on survival after SBRT.

Methods

Twenty-four prostate cancer patients were treated with SBRT at the Philadelphia CyberKnife Center between August 2007 and April 2014. Retrospective data collection and analysis were performed for these patients on this Institutional Review Board approved study. Kaplan–Meier methodology was utilized to estimate and visually assess overall survival (OS) at the patient level, with comparisons accomplished using the log-rank test. Unadjusted hazard ratios were estimated using Cox proportional hazards regression modeling.

Results

An improved median survival was noted for patients with oligometastatic disease defined as ≤4 lesions with median survival of >3 years compared with 11 months for polymetastases (p = 0.02). The use of docetaxel at some time in follow-up either before or after SBRT was associated with decreased survival with median survival of 9 months vs. >3 years (p = 0.01).

Conclusion

Prognosis was better for men with recurrent prostate cancer treated with SBRT if they had ≤4 metastases (oligometastases) or if docetaxel was not necessary for salvage treatment. The prolonged median OS for men with oligometastases in this population of heavily pretreated prostate cancer patients following SBRT may allow for improved quality of life because of a delay of more toxic salvage therapies.

International consensus on use of focused ultrasound for painful bone metastases: Current status and future directions

Focused ultrasound surgery (FUS), in particular magnetic resonance guided FUS (MRgFUS), is an emerging non-invasive thermal treatment modality in oncology that has recently proven to be effective for the palliation of metastatic bone pain. A consensus panel of internationally recognised experts in focused ultrasound critically reviewed all available data and developed consensus statements to increase awareness, accelerate the development, acceptance and adoption of FUS as a treatment for painful bone metastases and provide guidance towards broader application in oncology. In this review, evidence-based consensus statements are provided for (1) current treatment goals, (2) current indications, (3) technical considerations, (4) future directions including research priorities, and (5) economic and logistical considerations.

Impact of metformin use on survival in locally-advanced, inoperable non-small cell lung cancer treated with definitive chemoradiation

BACKGROUND

We investigated survival outcomes in diabetic patients with non-small cell lung cancer (NSCLC) treated with concurrent metformin and definitive chemoradiation.

METHODS

This single-institution, retrospective cohort study included 166 patients with NSCLC who were treated definitively with chemoradiation between 1999 and 2013. Of 40 patients who had type II diabetes, 20 (50%) were on metformin, and 20 (50%) were not on metformin. The primary outcome was overall survival (OS), and secondary outcomes included progression-free survival (PFS), locoregional recurrence-free survival (LRRFS) and distant metastasis-free survival (DMFS). Kaplan Meier method and log-rank test were performed in survival analysis. Cox regression was utilized in univariate analysis of potential confounders.

RESULTS

Median follow-up was 17.0 months. Compared with non-diabetic patients, diabetic patients on metformin demonstrated similar OS (16.3 vs. 14.3 mo, P=0.23), PFS (11.6 vs. 9.7 mo, P=0.26), LRRFS (14.1 vs. 11.9 mo, P=0.78), and DMFS (13.4 vs. 10.0 mo, P=0.69). Compared with diabetic patients not on metformin, diabetic patients on metformin also exhibited similar OS (14.3 vs. 19.2 mo, P=0.18), PFS (19.7 vs. 10.1 mo, P=0.38), LRRFS (11.9 vs. 15.5 mo, P=0.69), and DMFS (10.0 vs. 17.4 mo, P=0.12). Identified negative prognostic factors on included squamous cell histology, lower performance status, higher T stage, and non-caucasian ethnicity.

CONCLUSIONS

No statistically significant differences in survival or patterns of failure were found among the three cohorts in this small set of patients. No statistically significant differences in survival or patterns of failure were found between the three cohorts in this small set of patients. Though it is possible that metformin use may in fact have no effect on survival in NSCLC patients treated with definitive RT, larger-scale retrospective and prospective studies are implicated for clarification.

The biology and treatment of oligometastatic cancer

Clinical reports of limited and treatable cancer metastases, a disease state that exists in a transitional zone between localized and widespread systemic disease, were noted on occasion historically and are now termed oligometastasis. The ramification of a diagnosis of oligometastasis is a change in treatment paradigm, i.e. if the primary cancer site (if still present) is controlled, or resected, and the metastatic sites are ablated (surgically or with radiation), a prolonged disease-free interval, and perhaps even cure, may be achieved. Contemporary molecular diagnostics are edging closer to being able to determine where an individual metastatic deposit is within the continuum of malignancy. Preclinical models are on the outset of laying the groundwork for understanding the oligometastatic state. Meanwhile, in the clinic, patients are increasingly being designated as having oligometastatic disease and being treated owing to improved diagnostic imaging, novel treatment options with the potential to provide either direct or bridging therapy, and progressively broad definitions of oligometastasis.

Clinical Predictors of Survival for Patients with Stage IV Cancer Referred to Radiation Oncology

BACKGROUND

There is an urgent need for a robust, clinically useful predictive model for survival in a heterogeneous group of patients with metastatic cancer referred to radiation oncology.

METHODS

From May 2012 to August 2013, 143 consecutive patients with stage IV cancer were prospectively evaluated by a single radiation oncologist. We retrospectively analyzed the effect of 29 patient, laboratory and tumor-related prognostic factors on overall survival using univariate analysis. Variables that were statistically significant on univariate analysis were entered into a multivariable Cox regression to identify independent predictors of overall survival.

RESULTS

The median overall survival was 5.5 months. Four prognostic factors significantly predicted survival on multivariable analysis including ECOG performance status (0-1 vs. 2 vs. 3-4), number of active tumors (1 to 5 vs. ≥ 6), albumin levels (≥ 3.4 vs. 2.4 to 3.3 vs. < 2.4 and primary tumor site (Breast, Kidney or Prostate vs. Other). Risk group stratification was performed by assigning points for adverse prognostic factors resulting in very low, low, intermediate and high risk groups. The median survival was > 31.4 months for very low risk patients compared to 14.5 months for low risk, 4.1 months for intermediate risk and 1.2 months for high risk (p < 0.001).

CONCLUSIONS

These data suggest that a model that considers performance status, extent of disease, primary tumor site and serum albumin represents a simple model to accurately predict survival for patients with stage IV cancer who are potential candidates for radiation therapy.

Colorectal Histology Is Associated With an Increased Risk of Local Failure in Lung Metastases Treated With Stereotactic Ablative Radiation Therapy

PURPOSE

Stereotactic ablative radiation therapy (SABR) is increasingly used to treat lung oligometastases. We set out to determine the safety and efficacy of this approach and to identify factors associated with outcomes.

METHODS AND MATERIALS

We conducted a retrospective study of patients treated with SABR for metastatic lung tumors at our institution from 2003 to 2014. We assessed the association between various patient and treatment factors with local failure (LF), progression, subsequent treatment, systemic treatment, and overall survival (OS), using univariate and multivariate analyses.

RESULTS

We identified 122 tumors in 77 patients meeting inclusion criteria for this study. Median follow-up was 22 months. The 12- and 24-month cumulative incidence rates of LF were 8.7% and 16.2%, respectively; the 24-month cumulative incidence rates of progression, subsequent treatment, and subsequent systemic treatment were 75.2%, 64.5%, and 35.1%, respectively. Twenty-four-month OS was 74.6%, and median OS was 36 months. Colorectal metastases had a significantly higher cumulative incidence of LF at 12 and 24 months (25.5% and 42.2%, respectively), than all other histologies (4.4% and 9.9%, respectively; P<.0004). The 24-month cumulative incidences of LF for colorectal metastases treated with a biologically effective dose at α/β = 10 (BED10) of <100 Gy versus BED10 of ≥100 Gy were 62.5% and 16.7%, respectively (P=.08). Toxicity was minimal, with only a single grade 3 or higher event observed.

CONCLUSIONS

SABR for metastatic lung tumors appears to be safe and effective with excellent local control, treatment-free intervals, and OS. An exception is metastases from colorectal cancer, which have a high LF rate consistent with a radioresistant phenotype, suggesting a potential role for dose escalation.

Contemporary treatment with radiosurgery for spine metastasis and spinal cord compression in 2015

With the progress of image-guided localization, body immobilization system, and computerized delivery of intensity-modulated radiation delivery, it became possible to perform spine radiosurgery. The next question is how to translate the high technology treatment to the clinical application. Clinical trials have been performed to demonstrate the feasibility of spine radiosurgery and efficacy of the treatment in the setting of spine metastasis, leading to the randomized trials by a cooperative group. Radiosurgery has also demonstrated its efficacy to decompress the spinal cord compression in selected group of patients. The experience indicates that spine radiosurgery has a potential to change the clinical practice in the management of spine metastasis and spinal cord compression.

Stereotactic body radiotherapy for liver metastases

The role for local ablative therapies in the management paradigm of oligometastatic liver disease is increasing. The evidence base supporting the use of stereotactic body radiotherapy for liver metastases has expanded rapidly over the past decade, showing high rates of local control with low associated toxicity. This review summarises the evidence base to date, discussing optimal patient selection, challenges involved with treatment delivery and optimal dose and fractionation. The reported toxicity associated with liver stereotactic body radiotherapy is presented, together with possible pitfalls in interpreting the response to treatment using standard imaging modalities. Finally, potential avenues for future research in this area are highlighted.

Evaluation of stereotactic body radiation therapy in the management of adrenal metastases from non-small cell lung cancer

AIMS AND BACKGROUND

In this retrospective analysis, we evaluated the use of stereotactic body radiation therapy in the management of adrenal metastases from non-small cell lung cancer and report our single center experience.

METHODS AND STUDY DESIGN

Fifteen non-small cell lung cancer patients (9 male, 6 female) with 17 adrenal metastases referred to Gulhane Military Medical Academy Radiation Oncology Department were treated using active breathing control-guided stereotactic body radiation therapy between December 2009 and October 2013. Dose per fraction was 10 Gy to deliver a total dose of 30 Gy over 3 consecutive days for all metastatic adrenal lesions. The mean gross tumor volume was 28.4 cc (range 6.6-101.5) and mean planning target volume was 57.4 cc (range 16.5-143.8).

RESULTS

At a median follow-up of 16 months, local control was 86.7% and overall survival was 33.3%. Median disease-free survival was 10 months. Treatment response according to RECIST was categorized as complete response in 3 patients (20%), partial response in 5 patients (33.3%), stable disease in 5 patients (33.3%), and progressive disease in 2 patients (13.3%). Most common acute toxicity was grade 1 nausea (n = 7) and grade 1 fatigue (n = 12). There was no case of grade ≥3 acute or late toxicity.

CONCLUSIONS

Stereotactic body radiation therapy offers a safe and efficacious management strategy for adrenal metastases from non-small cell lung cancer by providing excellent local control with negligible treatment related toxicity.

Metastasectomy for stage IV melanoma

Metastatic melanoma has an unpredictable natural history but a predictably high mortality. Despite recent advances in systemic therapy, many patients do not respond, or develop resistance to drug therapy. Surgery has consistently shown good outcomes in appropriately selected patients. It is likely to be even more successful in the era of more effective medical treatment. Surgery should remain a strongly considered option for metastatic melanoma.

Effect on survival of local ablative treatment of metastases from sarcomas: a study of the French sarcoma group

AIMS

Recent data suggest that patients with pulmonary metastases from sarcomas might benefit from ablation of their metastases. Some data are available regarding osteosarcomas/angiosarcomas and lung metastases. The purpose of this study was to assess the efficacy of local ablative treatment on the survival of patients with oligometastases (one to five lesions, any metastatic site, any grade/histology) from sarcomas.

MATERIALS AND METHODS

A multicentric retrospective study of the French Sarcoma Group was conducted in sarcoma patients with oligometastases who were treated between 2000 and 2012. Survival was analysed using multivariate sensitivity analyses with propensity scores to limit bias.

RESULTS

Of the 281 patients evaluated, 164 patients received local treatment for oligometastases between 2000 and 2012. The groups' characteristics were similar in terms of tumour size and remission of the primary tumours. The median follow-up was 25.7 months; 129 (45.9%) patients had died at this point. The median overall survivals were 45.3 (95% confidence interval = 34-73) months for the local treatment group and 12.6 for the other group (95% confidence interval = 9.33-22.9). Survival was better among patients who received local treatment (hazard ratio = 0.47; 95% confidence interval = 0.29-0.78; P < 0.001). Subgroup analyses revealed similar findings in the patients with single oligometastases (hazard ratio = 0.48; 95% confidence interval = 0.28-0.82; P = 0.007); a significant benefit was observed for grade 3, and a trend was observed for grade 2.

CONCLUSION

Local ablative treatment seemed to improve the overall survival of the patients who presented with oligometastatic sarcomas, including soft tissue and bone sarcomas. The survival benefit remained after repeated local treatments for several oligometastatic events. Surgery yielded the most relevant results, but alternative approaches (i.e. radiofrequency ablation and radiotherapy) seemed to be promising. The relevance of these results is strengthened by our analysis, which avoided biases by restricting the population to patients with oligometastatic disease and used propensity scores.

Stereotactic ablative radiation therapy as first local therapy for lung oligometastases from colorectal cancer: a single-institution cohort study

PURPOSE

To estimate stereotactic ablative radiation therapy (SABR) efficacy and its potential role as an alternative to surgery for the treatment of lung metastases from colorectal cancer.

METHODS AND MATERIALS

Forty consecutive patients who received SABR as first local therapy at the time of lung progression were included, from 2004 to 2014. The primary study endpoint was overall survival. Secondary endpoints were progression-free survival and safety.

RESULTS

A single nodule was treated in 26 patients (65%), 2 nodules in 10 patients (25%), 3 in 3 patients (7.5%), and 4 in 1 patient (2.5%), for a total of 59 lesions. The median delivered biological effective dose was 96 Gy, in 1 to 8 daily fractions. Median follow-up time was 20 months (range, 3-72 months). Overall survival rates at 1, 2, and 5 years were, respectively, 84%, 73%, and 39%, with 14 patients (35%) dead. Median overall survival was 46 months. Progression occurred in 25 patients (62.5%), at a median interval of 8 months; failure at SABR site was observed in 3 patients (7.5%). Progression-free survival rates were 49% and 27% at 1 and 2 years, respectively.

DISCUSSION

The results of this retrospective exploratory analysis suggest safety and efficacy of SABR in patients affected with colorectal cancer lung oligometastases and urge inclusion of SABR in prospective clinical trials.

Combined ablation and resection (CARe) as an effective parenchymal sparing treatment for extensive colorectal liver metastases

BACKGROUND

Combined intra-operative ablation and resection (CARe) is proposed to treat extensive colorectal liver metastases (CLM). This multicenter study was conducted to evaluate overall survival (OS), local recurrence-free survival (LRFS), hepatic recurrence-free survival (HRFS) and progression-free survival (PFS), to identify factors associated with survival, and to report complications.

MATERIALS AND METHODS

Four centers combined retropectively their clinical experiences regarding CLM treated by CARe. CLM characteristics, pre- and post-operative chemotherapy regimens, surgical procedures, complications and survivals were analyzed.

RESULTS

Of the 288 patients who received CARe, 210 (73%) had synchronous and 255 (88%) had bilateral CLM. Twenty-two patients (8%) had extrahepatic disease. Median follow-up was 3.17 years (95%CI 2.83-4.08). Median OS was 3.33 years (95%CI 3.08-4.17) and 5-year OS was 37% (95%CI 29-45). One- and 5-year LRFS from ablated lesions were 87.9% (95%CI 83.3-91.2) and 78.0% (95%CI 71-83), respectively. Median HRFS and PFS were 14 months (95%CI 11-18) and 9 months (95%CI 8-11), respectively. One hundred patients experienced complications: 29 grade I, 68 grade II-III-IV, and three deaths. In the multivariate models adjusted for center, the occurrence of complications was confirmed as a major independent factor associated with 3-year OS (HR 1.80; P = 0.008). Five-year OS was 25.6% (95%CI 14.9-37.6) for patients with complications and 45% (95%CI 33.3-53.4) for patients without.

CONCLUSIONS

Recent strategies facing advanced CLM include non-anatomic resections, portal-induced hypertrophy of the future remnant liver and aggressive medical preoperative treatments. CARe has the qualities of an approach that allows effective tumor clearance while maintaining good tolerance for the patient.