Oligo-Metastatic Cancers: Putative Biomarkers, Emerging Challenges and New Perspectives

Clinical and genetic drivers of oligo-metastatic disease in colon cancer

BACKGROUND

Oligo-metastatic disease (OMD) in colon cancer patients exhibits distinct clinical behavior compared to poly-metastatic disease (PMD), with a more responsive and indolent course. This study aims to identify clinical and biological factors uniquely associated with oligo-metastatic behavior.

METHODS

Metastatic colon cancer patients from an academic center underwent genetic characterization. OMD was defined as ≤3 lesions per organ, each with a total diameter <70 mm and none exceeding 25 mm. Tumor DNA sequencing by NGS utilized the TruSight Oncology 500 kit. Overall survival (OS) was determined from metastasis diagnosis until death using Kaplan-Meier analysis. Multivariate Cox regression examined prognostic links between clinicopathological and genetic factors. Associations with metastatic patterns were evaluated using Chi-square.

RESULTS

The analysis involved 104 patients (44 with OMD, 60 with PMD). OMD was more prevalent in males (P = 0.0299) and with single organ involvement (P = 0.0226). Multivariate analysis adjusted for age (>70 vs. <70 years), gender (male vs. female), tumor side (right vs. left), metastatic involvement (more than one site vs. one site), response to first-line therapy (disease control vs. no disease control), and RAS/BRAF variants (wild-type vs. mutated) identified OMD vs. PMD as the strongest independent predictor of survival (HR: 0.14; 95 % CI: 0.06-0.33; P<0.0001). OMD patients exhibited distinct molecular characteristics, including lower frequencies of BRAF p.V600E (P=0.0315) and KRAS mutations (P=0.0456), as well as a higher frequency of high tumor mutational burden (P=0.0127). Additionally, by integrating data from public datasets and our case study, we hypothesize that some gene alterations (i.e.: BRAF, SMAD4, RAF1, and mTOR) may prevent OMD occurrence.

CONCLUSION

OMD, characterized by male predominance, single-site involvement, and distinct molecular features in colon cancer, suggests the need for tailored management strategies.

Current Treatment Paradigms and Clinical Outcomes in Oligometastatic Prostate Cancer Patients: A Targeted Literature Review

CONTEXT

Prostate cancer is the most common noncutaneous malignancy among men in the USA and Europe. There is no consensus definition of oligometastatic prostate cancer (omPC), which is often considered in two subgroups, synchronous (de novo) and metachronous (oligorecurrent), and may include patients with a low metastatic disease burden.

OBJECTIVE

To summarize the epidemiology, disease definitions, mortality/survival outcomes, and treatment characteristics in both clinical trial and real-world settings among patients with synchronous, metachronous, and mixed-subtype (ie, synchronous and metachronous or undefined type) omPC, as well as low burden disease states.

EVIDENCE ACQUISITION

We searched MEDLINE and Embase to identify publications reporting on epidemiology, disease definitions, clinical outcomes, and treatment characteristics of omPC. Gray literature sources (eg, ClinicalTrials.gov) were searched for ongoing trials.

EVIDENCE SYNTHESIS

We identified 105 publications. Disease definitions varied across publications and omPC subtypes on the number and location of lesions, type of imaging used, and type of oligometastatic disease. Most studies defined omPC as five or fewer metastatic lesions. Data on the epidemiology of omPC were limited. Mortality rates and overall survival tended to be worse among synchronous versus metachronous omPC cohorts. Progression-free survival was generally longer among synchronous than among metachronous omPC cohorts but was more similar at longer time points. A summary of ongoing clinical trials investigating a variety of local, metastasis-directed, and systemic therapies in men with omPC is also provided.

CONCLUSIONS

Definitions of oligometastatic disease depend on the imaging technique used. Epidemiologic data for omPC are scarce. Survival rates differ between synchronous and metachronous cohorts, and heterogeneous treatment patterns result in varied outcomes. Ongoing clinical trials using modern imaging techniques are awaited and needed.

PATIENT SUMMARY

Definitions of oligometastatic prostate cancer (omPC) vary depending on the imaging technique used. Different treatment patterns lead to different outcomes. Robust omPC epidemiologic data are lacking.

Widely-targeted in silico and in vitro evaluation of veratrum alkaloid analogs as FAK inhibitors and dual targeting of FAK and Hh/SMO pathways for cancer therapy: A critical analysis

Focal Adhesive Kinase (FAK), a key player in aggressive cancers, mediates signals crucial for progression, invasion, and metastasis. Despite advances in targeted therapies, drug resistance is still a challenge, and survival rates remain low, particularly for late-stage patients, emphasizing the need for innovative cancer therapeutics. Cyclopamine, a veratrum alkaloid, has shown promising anti-tumor properties, but the search for more potent analogs with enhanced affinity for the biological target continues. This study employs a hybrid virtual screening approach combining pharmacophore model-based virtual screening (PB-VS) and docking-based virtual screening (DB-VS) to identify potential inhibitors of the FAK catalytic domain. PB-VS on the PubChem database yielded a set of hits, which were then docked with the FAK catalytic domain in two stages (1st and 2nd DB-VS). Hits were ranked based on docking scores and interactions with the active site. The top three compounds underwent molecular dynamics simulations, alongside two control compounds (SMO inhibitor(s) and FAK inhibitor(s)), to assess stability through RMSD, RMSF, Rg, and SASA analyses. ADMET properties were evaluated, and compounds were filtered based on drug-likeness criteria. Molecular dynamics simulations demonstrated the stability of compounds when complexed with the FAK catalytic domain. Compounds 16 (-25 kcal/mol), 87 (-27.47 kcal/mol), and 88 (-18.94 kcal/mol) exhibited comparable docking scores, interaction profiles, stability, and binding energies, indicating their potential as lead candidates. However, further validation and optimization through quantitative structure-activity relationship (QSAR) studies are essential to refine their efficacy and therapeutic potential. The in vitro cell-based assay demonstrated that compound 101PF, a FAK inhibitor, significantly inhibited the proliferation and migration of A549 cells. However, the results regarding the combined effects of FAK and SMO inhibitors were inconclusive, highlighting the need for further investigation. This study contributes to developing more effective anti-cancer drugs by improving the understanding of potential cyclopamine-based veratrum alkaloid analogs with enhanced interactions with the FAK catalytic domain.

Prognostic factors of early recurrence after complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

BACKGROUND

Although cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) offer the potential for long-term survival in peritoneal carcinomatosis, outcomes following CRS/HIPEC vary significantly.

AIM

To identify the clinical factors associated with progression-free survival (PFS) after complete CRS/HIPEC in patients with colorectal/high-grade appendiceal, ovarian, and gastric cancers.

METHODS

We retrospectively evaluated the risk of recurrence within 1 year after CRS/HIPEC and its impact on overall survival (OS) in patients recruited between 2015 and 2020. Logistic regression models were used to assess the prognostic factors for the risk of recurrence within 1 year. Kaplan-Meier survival curves and Cox proportional hazards models were used to evaluate the association between recurrence and OS.

RESULTS

Of the 80 enrolled patients, 39 had an unfavorable PFS (< 1 year) and 41 had a favorable PFS (≥ 1 year). Simple logistic models revealed that the patients with a completeness of cytoreduction score of 0 (CC-0) or length of CRS ≤ 6 h had a favorable PFS [odds ratio (OR) = 0.141, P = 0.004; and OR = 0.361, P = 0.027, respectively]. In multiple logistic regression, achieving CC-0 was the strongest prognostic factor for a favorable PFS (OR = 0.131, P = 0.005). A peritoneal cancer index score > 12 was associated with a lower rate of achieving CC-0 (P = 0.027). The favorable PFS group had a significantly longer OS (median 81.7 mo vs 17.0 mo, P < 0.001).

CONCLUSION

Achieving CC-0 was associated with a lower early recurrence rate and improved long-term survival. This study underscores the importance of selecting appropriate candidates for CRS/HIPEC to manage peritoneal carcinomatosis.

A randomized phase III trial of stereotactic ablative radiotherapy for patients with up to 10 oligometastases and a synchronous primary tumor (SABR-SYNC): study protocol

BACKGROUND

Emerging randomized data, mostly from phase II trials, have suggested that patients with oligometastatic cancers may benefit from ablative treatments such as stereotactic ablative radiotherapy (SABR). However, phase III data testing this paradigm are lacking, and many studies have examined SABR in the setting of metachronous oligometastatic disease. The goal of the SABR-SYNC trial is to assess the effect of SABR in patients with oligometastatic cancers and a synchronous primary tumor.

METHODS

One hundred and eighty patients will be randomized in a 1:2 ratio between standard of care (SOC) palliative-intent treatments vs. SOC + ablative therapy (SABR preferred) to all sites of known disease. Randomization will be stratified based on histology and number of metastases at enrollment. SABR may be delivered in 1-, 3- and 5-fraction regimens, with recommended doses of 20 Gy, 30 Gy, and 35 Gy, respectively. Non-SABR local modalities (e.g. surgery, thermal ablation, conventional radiation) may be used for treatment of the primary or metastases at the discretion of the treating physicians, if those modalities are clinically preferred. The primary endpoint is overall survival, and secondary endpoints include progression-free survival, time to development of new metastatic lesions, time to initiation of next systemic therapy, quality of life, and toxicity. Translational endpoints include assessment of circulating tumor DNA and immunological predictors of outcomes.

DISCUSSION

SABR-SYNC will provide phase III data to assess the impact of SABR on overall survival in a population of patients with synchronous oligometastases. The translational component will attempt to identify novel prognostic and predictive biomarkers to aid in clinical decision making.

TRIAL REGISTRATION

Clinicaltrials.gov NCT05717166 (registration date: Feb. 8, 2023).

De novo versus recurrent metastatic breast cancer affects the extent of brain metastases

PURPOSE

We aimed to identify factors associated with the extent of brain metastases in patients with breast cancer to help distinguish brain oligometastases (1-4 brain metastases) from extensive metastases (5 or more brain metastases).

METHODS

This retrospective observational study included 100 female patients diagnosed with brain metastases from breast cancer at a single institution between January 2011 and April 2022. Patient demographics and tumor characteristics were compared between the brain oligometastases group and the extensive metastases group. Multivariable logistic regression analysis was performed to determine the independent factors, including age at initial diagnosis, initial stage, breast cancer subtype, detection time of brain metastases, and de novo or recurrent status of the metastatic disease. In a subgroup analysis of patients with brain oligometastases, demographic and tumor characteristics were compared between patients with single and two-four brain metastases.

RESULTS

Of the 100 patients, 56 had brain oligometastases, while 44 had extensive brain metastases. The multivariable logistic regression analysis revealed that only the de novo/recurrent status of metastatic breast cancer was significantly associated with the extent of brain metastasis (p = 0.023). In the subgroup analysis of 56 patients with brain oligometastases, those diagnosed at an earlier stage were more likely to have a single brain metastasis (p = 0.008).

CONCLUSION

Patients with de novo metastatic breast cancer are more likely to develop extensive brain metastases than those with recurrent metastatic breast cancer. This insight could influence the development of tailored approaches for monitoring and treating brain metastases, supporting the potential advantages of routine brain screening for patients newly diagnosed with stage IV breast cancer.

Overview of Radiation Therapy in the Management of Localized and Metastatic Prostate Cancer

PURPOSE OF REVIEW

The goal is to describe the evolution of radiation therapy (RT) utilization in the management of localized and metastatic prostate cancer.

RECENT FINDINGS

Long term data for a variety of hypofractionated definitive RT dose-fractionation schemes has matured, allowing patients and providers many standard-of-care options to choose from. Post-prostatectomy, adjuvant RT has largely been replaced by an early salvage approach. Multiparametric MRI and PSMA PET have enabled increasingly targeted RT delivery to the prostate and oligometastatic tumors. Areas of active investigation include determining the value of proton beam therapy and perirectal spacers, and optimally incorporate genomic tumor profiling and next generation hormonal therapies with RT in the curative setting. The use of radiation therapy to treat prostate cancer is rapidly evolving. In the coming years, there will be continued improvements in a variety of areas to enhance the value of RT in multidisciplinary prostate cancer management.

Evaluation of secondary cytoreduction surgery in platinum-resistant ovarian cancer patients within three-line recurrent: a multicenter, randomized controlled study

BACKGROUND

Epithelial ovarian cancer is the leading cause of death among gynecological malignancies. Platinum resistance remains a dilemma and bottleneck in treatment, and salvage chemotherapy has limited effectiveness. Recently, the role of secondary cytoreductive surgery (SCS) in patients with platinum-resistant recurrent ovarian cancer (ROC) has caused attention especially in patients with oligometastases. However, there is neither high-quality evidence-based evidence nor standardized criteria for selecting SCS for patients with platinum-resistant ROC until now.

METHODS

This multicenter, randomized, controlled clinical trial is to evaluate the value of SCS and to clarify reliable criteria of utilizing SCS in women with ROC, which is led by Gynecologic Oncology Group, Women's Hospital, Zhejiang University School of Medicine. Recruitment has started on January 1st, 2023, and is scheduled to end in December 2026. One hundred and forty participants with platinum-resistant ROC who meet the "RSCS criteria" will be randomized assigned at a ratio of 1:1 to either the experimental arm or the standard arm. Patients in the experimental arm will receive SCS followed by non-platinum single agent chemotherapy (paclitaxel, gemcitabine or liposomal adriamycin) for at least 4 cycles while patients in the standard arm will be provided with only non-platinum single agent chemotherapy. The primary outcome is progression-free survival. The secondary outcomes are overall survival, adverse events and health-related cancer-specific quality of life.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05633199.

Oligo-Metastatic Disease in Oncology: Exploring the Limits and the Potential of Genetic Assessment

Oligo-metastatic disease (OMD) in the field of oncology denotes a distinct subset of metastatic tumors characterized by less aggressive biological behavior and extended survival times in comparison to their widely metastatic counterparts. While there is a general consensus regarding the existence of OMD, there remains a lack of widely accepted criteria for its a priori identification at the time of presentation. This review delves into the concept of OMD, placing a particular emphasis on the significance of understanding the limitations and potential of genetic assessments. It explores how these aspects are crucial in advancing our comprehension of this phenomenon. In a rapidly advancing era of precision medicine, understanding the intricacies of OMD opens up exciting possibilities for tailored treatment approaches. By elucidating the genetic underpinnings and dynamic nature of this condition, we stand to improve patient outcomes and potentially shift the paradigm of metastatic cancer management.

Circulating Tumor Cells as Predictive and Prognostic Biomarkers in Solid Tumors

Circulating tumor cells (CTCs) have emerged as pivotal biomarkers with significant predictive and prognostic implications in solid tumors. Their presence in peripheral blood offers a non-invasive window into the dynamic landscape of cancer progression and treatment response. This narrative literature review synthesizes the current state of knowledge surrounding the multifaceted role of CTCs in predicting clinical outcomes and informing prognosis across a spectrum of solid tumor malignancies. This review delves into the evolving landscape of CTC-based research, emphasizing their potential as early indicators of disease recurrence, metastatic potential, and therapeutic resistance. Moreover, we have underscored the dynamic nature of CTCs and their implications for personalized medicine. A descriptive and critical analysis of CTC detection methodologies, their clinical relevance, and their associated challenges is also presented, with a focus on recent advancements and emerging technologies. Furthermore, we examine the integration of CTC-based liquid biopsies into clinical practice, highlighting their role in guiding treatment decisions, monitoring treatment efficacy, and facilitating precision oncology. This review highlights the transformative impact of CTCs as predictive and prognostic biomarkers in the management of solid tumors by promoting a deeper understanding of the clinical relevance of CTCs and their role in advancing the field of oncology.

Oligo-metastatic neoPlasms from the gastro-intestinal tract: iDentIfiCaTIon of cliNical and molecular drivers: the PREDICTION study

BACKGROUND

Metastatic disease in tumors originating from the gastrointestinal tract can exhibit varying degrees of tumor burden at presentation. Some patients follow a less aggressive disease course, characterized by a limited number of metastatic sites, referred to as "oligo-metastatic disease" (OMD). The precise biological characteristics that define the oligometastatic behavior remain uncertain. In this study, we present a protocol designed to prospectively identify OMD, with the aim of proposing novel therapeutic approaches and monitoring strategies.

METHODS

The PREDICTION study is a monocentric, prospective, observational investigation. Enrolled patients will receive standard treatment, while translational activities will involve analysis of the tumor microenvironment and genomic profiling using immunohistochemistry and next-generation sequencing, respectively. The first primary objective (descriptive) is to determine the prevalence of biological characteristics in OMD derived from gastrointestinal tract neoplasms, including high genetic concordance between primary tumors and metastases, a significant infiltration of T lymphocytes, and the absence of clonal evolution favoring specific driver genes (KRAS and PIK3CA). The second co-primary objective (analytic) is to identify a prognostic score for true OMD, with a primary focus on metastatic colorectal cancer. The score will comprise genetic concordance (> 80%), high T-lymphocyte infiltration, and the absence of clonal evolution favoring driver genes. It is hypothesized that patients with true OMD (score 3+) will have a lower rate of progression/recurrence within one year (20%) compared to those with false OMD (80%). The endpoint of the co-primary objective is the rate of recurrence/progression at one year. Considering a reasonable probability (60%) of the three factors occurring simultaneously in true OMD (score 3+), using a significance level of α = 0.05 and a test power of 90%, the study requires a minimum enrollment of 32 patients.

DISCUSSION

Few studies have explored the precise genetic and biological features of OMD thus far. In clinical settings, the diagnosis of OMD is typically made retrospectively, as some patients who undergo intensive treatment for oligometastases develop polymetastatic diseases within a year, while others do not experience disease progression (true OMD). In the coming years, the identification of true OMD will allow us to employ more personalized and comprehensive strategies in cancer treatment.

TRIAL REGISTRATION

ClinicalTrials.gov ID NCT05806151.