Clinical outcomes of gastrointestinal brain metastases treated with radiotherapy

Outcomes Following Early Postoperative Adjuvant Radiosurgery for Brain Metastases

Importance

Adjuvant stereotactic radiosurgery (SRS) enhances the local control of resected brain metastases (BrM). However, the risks of local failure (LF) and potential for posttreatment adverse radiation effects (PTRE) after early postoperative adjuvant SRS have not yet been established.

Objective

To evaluate whether adjuvant SRS delivered within a median of 14 days after surgery is associated with improved LF without a concomitant increase in PTRE.

Design, Setting, and Participants

This prospective cohort study examines a clinical workflow (RapidRT) that was implemented from 2019 to 2022 to deliver SRS to surgical patients within a median of 14 days, ensuring all patients were treated within 30 days postoperatively. This prospective cohort was compared with a historical cohort (StanRT) of patients with BrM resected between 2013 and 2019 to assess the association of the RapidRT workflow with LF and PTRE. The 2 cohorts were combined to identify optimal SRS timing, with a median follow-up of 3.3 years for survivors.

Exposure

Timing of adjuvant SRS (14, 21, and 30 days postoperatively).

Main Outcomes and Measures

LF and PTRE, according to modified Response Assessment in Neuro-Oncology Brain Metastases criteria.

Results

There were 438 patients (265 [60.5%] female patients; 23 [5.3%] Asian, 27 [6.2%] Black, and 364 [83.1%] White patients) with a mean (SD) age of 62 (13) years; 377 were in the StanRT cohort and 61 in the RapidRT cohort. LF and PTRE rates at 1 year were not significantly different between RapidRT and StanRT cohorts. Timing of SRS was associated with radiographic PTRE. Patients receiving radiation within 14 days had the highest 1-year PTRE rate (18.08%; 95% CI, 8.31%-30.86%), and patients receiving radiation between 22 and 30 days had the lowest 1-year PTRE rate (4.10%; 95% CI, 1.52%-8.73%; P = .03). LF rates were highest for patients receiving radiation more than 30 days from surgery (10.65%; 95% CI, 6.90%-15.32%) but comparable for patients receiving radiation within 14 days, between 15 and 21 days, and between 22 and 30 days (≤14 days: 5.12%; 95% CI, 0.86%-15.60%; 15 to ≤21 days: 3.21%; 95% CI, 0.59%-9.99%; 22 to ≤30 days: 6.58%; 95% CI, 3.06%-11.94%; P = .20).

Conclusions and Relevance

In this cohort study of adjuvant SRS timing following surgical resection of BrM, the optimal timing for adjuvant SRS appears to be within 22 to 30 days following surgery. The findings of this study suggest that this timing allows for a balanced approach that minimizes the risks associated with LF and PTRE.

The Cognitive Effects of Radiotherapy for Brain Metastases

Brain metastases are the most common intracranial neoplasm and are seen in upwards of 10-30% of patients with cancer. For decades, whole brain radiation therapy (WBRT) was the mainstay of treatment in these patients. While WBRT is associated with excellent rates of intracranial tumor control, studies have demonstrated a lack of survival benefit, and WBRT is associated with higher rates of cognitive deterioration and detrimental effects on quality of life. In recent years, strategies to mitigate this risk, such as the incorporation of memantine and hippocampal avoidance have been employed with improved results. Furthermore, stereotactic radiosurgery (SRS) has emerged as an appealing treatment option over the last decade in the management of brain metastases and is associated with superior cognitive preservation and quality of life when compared to WBRT. This review article evaluates the pathogenesis and impact of cranial irradiation on cognition in patients with brain metastases, as well as current and future risk mitigation techniques.

Treatment of brain metastases from gastrointestinal primaries: Comparing whole-brain radiotherapy and stereotactic radiosurgery in terms of survival

Objective:

The objective of the study was to analyze the clinical features and prognostic factors for survival in patients with brain metastasis (BM) from gastrointestinal primaries treated with whole-brain radiotherapy (WBRT) or stereotactic radiosurgery (SRS).

Methods:

We retrospectively investigated patients with BMs resulting from gastrointestinal primaries who underwent WBRT or SRS. The effects of treatment modalities on overall survival (OS) were calculated by the Kaplan–Meier method.

Results:

WBRT and SRS were applied to 24 and 17 patients, respectively. In the WBRT group, radiotherapy was delivered at 20–30 Gy in 5–10 fractions (fx). In the SRS group, a median dose of 22 Gy (range: 18–27 Gy) was applied in 1–3 fx. At BM diagnosis, all patients had synchronous extracranial metastases which were mostly detected in the lung and liver. Median OS values were 9 months and 4 months in the SRS and WBRT groups, respectively (p=0.005). Karnofsky performance status (KPS) score (≥70 vs. <70), diagnosis-specific graded prognostic index, gastrointestinal (GI) graded prognostic index, cumulative intracranial tumor volume (CITV), controlled systemic disease, and treatment modality (WBRT vs. SBRT) were found to be related with OS.

Conclusion:

In patients with GI cancer-related BMs, SRS should be preferred in those with longer OS expectancy who have controlled extracranial disease, good KPS and CITV values of <10 cm³.

Stereotactic Radiosurgery Results for Patients With Brain Metastases From Gastrointestinal Cancer: A Retrospective Cohort Study of 802 Patients With GI-GPA Validity Test

Purpose

The role of stereotactic radiosurgery (SRS) alone for patients with gastrointestinal (GI) cancer has yet to be established based on a large patient series. We analyzed post-SRS treatment results and reappraised whether either the GI graded prognostic assessment (GPA) system or modified-recursive partitioning assessment (M-RPA) system was applicable to our 802 SRS-treated patients with GI cancer with brain metastases.

Methods and Materials

This was an institutional review board approved retrospective cohort study 2 database comprising 802 patients with GI cancer treated with gamma-knife SRS by 2 experienced neurosurgeons during the 1998 to 2018 period. The Kaplan-Meier method was applied to determine post-SRS survival times, and competing risk analyses were used to estimate cumulative incidences of the secondary endpoints.

Results

The median survival time (MST; months) after SRS was 5.7. With the GI GPA system, MSTs were 3.5/6.1/7.7/11.0 in the 4 subgroups, that is, 0 to 1.0/1.5 to 2.0/2.5 to 3.0/3.5 to 4.0, respectively (stratified P < .0001). However, there was no significant MST difference between 2 of the subgroups, GI-GPA 1.5 to 2.0 and 2.5 to 3.0 (P = .073). In contrast, using the M-RPA system, 3 plot lines corresponding to the 3 subgroups showed no overlap and the MST differences between the subgroups with M-RPA were 1 + 2a versus 2b (P < .0001) and 2b versus 2c + 3 (P < .0001). Better Karnofsky performance status score, solitary tumor, well-controlled primary cancer, and the absence of extracerebral metastases were shown by multivariable analysis to be significant predictors of longer survival. The crude and cumulative incidences of neurologic death, neurologic deterioration, local recurrence, salvage whole brain radiation therapy, and SRS-related complications did not differ significantly between the 2 patient groups, with upper and lower GI cancers.

Conclusions

This study clearly demonstrated the usefulness of the GI GPA. Patients with GI GPA 1.5 to 2.0 or better or M-RPA 2b or better are considered to be favorable candidates for treatment with SRS alone.

Durable 5-year local control for resected brain metastases with early adjuvant SRS: the effect of timing on intended-field control

Background

Adjuvant stereotactic radiosurgery (SRS) improves the local control of resected brain metastases (BrM). However, the dependency of long-term outcomes on SRS timing relative to surgery remains unclear.

Methods

Retrospective analysis of patients treated with metastasectomy-plus-adjuvant SRS at Memorial Sloan Kettering Cancer Center (MSK) between 2013 and 2016 was conducted. Kaplan-Meier methodology was used to describe overall survival (OS) and cumulative incidence rates were estimated by type of recurrence, accounting for death as a competing event. Recursive partitioning analysis (RPA) and competing risks regression modeling assessed prognostic variables and associated events of interest.

Results

Two hundred and eighty-two patients with BrM had a median OS of 1.5 years (95% CI: 1.2-2.1) from adjuvant SRS with median follow-up of 49.8 months for survivors. Local surgical recurrence, other simultaneously SRS-irradiated site recurrence, and distant central nervous system (CNS) progression rates were 14.3% (95% CI: 10.1-18.5), 4.9% (95% CI: 2.3-7.5), and 47.5% (95% CI: 41.4-53.6) at 5 years, respectively. Median time-to-adjuvant SRS (TT-SRS) was 34 days (IQR: 27-39). TT-SRS was significantly associated with surgical site recurrence rate (P = 0.0008). SRS delivered within 1 month resulted in surgical site recurrence rate of 6.1% (95% CI: 1.3-10.9) at 1-year, compared to 9.2% (95% CI: 4.9-13.6) if delivered between 1 and 2 months, or 27.3% (95% CI: 0.0-55.5) if delivered >2 months after surgery. OS was significantly lower for patients with TT-SRS >~2 months. Postoperative length of stay, discharge to a rehabilitation facility, urgent care visits, and/or disease recurrence between surgery and adjuvant SRS associated with increased TT-SRS.

Conclusions

Adjuvant SRS provides durable local control. However, delays in initiation of postoperative SRS can decrease its efficacy.

Validation of recursive partitioning analysis, graded prognostic assessment and basic score for brain metastases as prognostic indices among patients with brain metastases treated with radiotherapy in Indonesia

Introduction:

Metastatic brain disease is still a major contributor to cancer treatment failure. Various treatments have improved in the recent decades, which allow for better control of brain metastatic lesions. Various prognostic scoring tools have been developed and used worldwide to stratify patients with brain metastases to determine who will benefit most from aggressive treatment. The three most commonly used prognostic scoring tools are recursive partitioning analysis (RPA), basic score for brain metastases (BSBM) and graded prognostic assessment (GPA). The aim of this study is to validate these scoring tools using an Indonesian cancer patient population.

Method:

A retrospective analysis of all patients presenting with brain metastases from January 2012 until December 2014, through using hospital medical records, was conducted. All patients receiving whole brain radiotherapy during this period were included in this study. A follow-up with a telephone call was carried out to determine the patient’s health and survival status. Uncontactable patients were excluded from the analysis. Survival analysis was carried out by stratifying patients based on the three prognostic scoring systems.

Result:

A total of 80 patients were eligible to be included in the study, with 18 excluded due to being uncontactable. The remaining 62 patients’ data were analysed and stratified with all three scoring systems. The RPA was found to confer better stratification than BSBM and GPA in our study population.

Conclusion:

GPA was non-prognostic in our study population and BSBM was less prognostic, especially in the middle group, class 1 and class 2. Those BSBM class 1 and class 2 did not provide good prognostic stratification in our study population, whereas RPA was proven to be the best in stratifying patients’ prognosis with brain metastases in our study population.

Single-Fraction Radiosurgery Using Conservative Doses for Brain Metastases: Durable Responses in Select Primaries With Limited Toxicity

BACKGROUND

Optimal doses for single-fraction stereotactic radiosurgery (SRS) in the treatment of brain metastases are not well established. Our institution utilized conservative dosing compared to maximum-tolerated doses from the Radiation Therapy Oncology Group 90-05 Phase I study.

OBJECTIVE

To report individual lesion control (LC) from conservative single-fraction doses and determine factors affecting LC.

METHODS

From 2003 to 2015, patients who underwent linear accelerator-based single-fraction SRS for cerebral/cerebellar metastases and receiving at least 1 follow-up magnetic resonance imaging (MRI) were identified. Lesion response was assessed by a size-based rating system and modified "Response Assessment in Neuro-Oncology Brain Metastases" (RANO-BM) criteria.

RESULTS

Among 188 patients with 519 lesions, median survival was 13.1 mo; median follow-up time with MRI was 9.6 mo per course. Median tumor-periphery dose was 15 Gy (range: 7.5-20.7). Median lesion volume was 0.5 cc and diameter was 9 mm (range: 2-45). Concordance between RANO-BM and size-based system was 93%. Crude 1-yr LC was 80%, 73%, 56%, and 38% for lesions 1 to 10, 11 to 20, 21 to 30, >31 mm, respectively. On multivariate analysis, increased size, melanoma and colorectal histology, and progression after whole brain radiation therapy predicted worse LC. When excluding lesions treated as a boost, dose was a significant predictor of LC in multivariate models (hazard ratio 0.89, P = .01). Symptomatic radiation necrosis occurred in 10 lesions in 10 patients.

CONCLUSION

Histology predicts LC after conservative SRS doses with evidence of a dose-response relationship. Conservative single-fraction SRS doses confer minimal toxicity and acceptable control in certain subgroups (breast cancer, <5 mm), with suboptimal control in larger lesions and in combination with whole brain radiation therapy.

Stereotactic radiosurgery for the treatment of brain metastasis from gastrointestinal primary cancers

PURPOSE

We aimed to determine the efficacy of gamma knife stereotactic radiosurgery (SRS) to control brain metastases (BM) from GI primaries and report on the patient outcomes.

MATERIALS/METHODS

We retrospectively evaluated patients who had undergone SRS at our institution for the treatment BM from GI primaries from 2000 to 2016. Actuarial rates for overall survival (OS) and local control (LC) were calculated. Survival rates were computed via the Kaplan-Meier method from the day of SRS. Multivariate analysis (MVA) using proportional hazards regression was done to determine prognostic factors for OS and LC.

RESULTS

53 patients with a total of 148 BM were treated with SRS. The median age at SRS was 60 years and the median treatment dose was 18 Gy. SRS was given as an adjuvant treatment to 30.4% of lesions. Twelve patients underwent second course of SRS for new/recurrent lesions at a median of 8 months from the first SRS (range 2-25.5). Twelve patients (22.6%) received salvage whole brain radiation. The median follow up time from the diagnosis of BM was 6 months. Local control rate at 6 months was 74.33% and 57.21% at 12 months. The OS at 1 year was 34% and 8% at 3 years. On MVA, higher GK dose was associated with better LC, and and >10 BM trended towards higher risk of local recurrence (LR). None of the tested factors proved to be significant for OS on MVA. No radiographic radionecrosis was observed on follow up MRI.

CONCLUSIONS

SRS is a safe treatment modality for the management of CNS metastases from GI primary. Consideration for dose-escalated approaches may improve LC rates.

Stereotactic Radiosurgery and Immune Checkpoint Inhibitors in the Management of Brain Metastases

Brain metastases traditionally carried a poor prognosis with an overall survival of weeks to months in the absence of treatment. Radiation therapy modalities include whole brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS). WBRT delivers a relatively low dose of radiation, has neurocognitive sequelae, and has not been investigated for its immunostimulatory effects. Furthermore, WBRT exposes the entire intracranial tumor immune microenvironment to radiation. SRS delivers a high dose of conformal radiation with image guidance to minimize dose to surrounding normal brain tissue, and appears to promote anti-tumor immunity. In parallel with many of these discoveries, immune checkpoint inhibitors (ICIs) have demonstrated a survival advantage in multiple malignancies commonly associated with brain metastases (e.g., melanoma). Combination SRS and ICI are theorized to be synergistic in anti-tumor immunity directed to brain metastases. The purpose of this review is to explore the synergy of SRS and ICIs, including pre-clinical data, existing clinical data, and ongoing prospective trials.

Brain metastasis in colorectal cancer presenting as refractory hypertension

Background: Brain metastasis (BM) from colorectal cancer (CRC) is rare with the incidence ranging from 0.6% to 3.2%. There is also an increased incidence of BM with rectal primaries and is consistent with this patient’s presentation. Overall, there is scarce literature on the symptoms of patients who present with CRC BMs.

Objectives: We present a case of brain metastasis in colorectal cancer presenting with hypertensive urgency and severe headache.

Methods and results: This case highlights that neurological deficits are not necessary for BMs in patients with CRC and summarizes and reviews the associated literature regarding BM in CRC. A 57-year-old female with a past medical history of recently diagnosed stage IV moderately differentiated distal rectal adenocarcinoma with liver and lung metastasis was admitted with the primary complaint of hypertensive urgency, severe headache, intractable nausea and vomiting, and diarrhea. Magnetic resonance imaging brain showed a left cerebellar lesion measuring 3.6 × 3.2 × 2.9 cm, ipsilateral transtentorial herniation, and obliteration of the fourth ventricle. The patient was started on steroids and transferred for an urgent neurosurgical intervention to a tertiary care center.

Conclusions: Even though BMs are rare in CRC, clinicians should have a high index of suspicion with complaints like hypertensive urgency, headache, nausea, vomiting, vertigo, and blurring of vision triggering imaging studies to rule out BM. The approach to BM has become increasingly individualized as surgical and radiosurgical therapies have continued to evolve

Abbreviations: CRC: Colorectal cancer; BM: Brain metastasis; FOLFOX: Folinic acid, fluorouracil and oxaliplatin; CT: Computed tomography; IV: Intravenous; PO: By mouth; BAER: Brain auditory evoked response hearing testing; SSEP’s: Somatosensory evoked potentials; BMFI: Brain metastasis free interval; WBRT: Whole-brain radiation therapy; SRS: Stereotactic radiosurgery.