Brain enveloped in light symbolizing radiation therapy's impact on cancer cells.

Radiation Therapy and Cancer: Unveiling Its Impact on Survival Rates

Beau Callahan in Health & Wellness August 2025 • 4 min read.

"A Deep Dive into How Radiation Therapy Affects Leptomeningeal Carcinomatosis and What Factors Influence Treatment Success"

Leptomeningeal carcinomatosis (LMC), a condition where cancer spreads to the membranes surrounding the brain and spinal cord, affects approximately 5% of all cancer patients. This complication disrupts the central nervous system, leading to significant health challenges. Without intervention, the median survival is a grim 4-6 weeks, but treatment can extend this to 8-12 weeks. Over recent decades, LMC incidence has risen due to enhanced diagnostic tools and improved cancer treatments, ironically increasing the risk of cancer cells invading the subarachnoid space.

While intrathecal chemotherapy, which involves direct drug delivery into the cerebrospinal fluid (CSF), remains a primary treatment, radiation therapy (RT) is often used alongside it to target specific sites and alleviate pressure. However, the overall survival benefits of RT are less conclusive, partly due to the poor prognosis and rapid neurological deterioration associated with LMC, making randomized trials difficult. Therefore, RT is often considered a supplementary therapy.

To clarify the effectiveness of RT, a comprehensive review was conducted to assess its impact on survival in LMC patients with primary breast or lung cancers. This analysis identifies key factors that determine which patients experience a survival benefit from RT, aiming to provide a more targeted and effective approach to treatment.

Who Benefits from Radiation Therapy? Key Factors Identified

Brain enveloped in light symbolizing radiation therapy's impact on cancer cells.

A systematic review was conducted, analyzing studies that included information on patient profiles, such as age, median survival, diagnosis timeline, cancer type, treatments received, performance score, and presence of systemic disease. Studies were excluded if they were case reports, written in languages other than English, or lacked detailed patient profiles.

For LMC patients with primary breast cancer, seven studies met the inclusion criteria. These studies helped identify several factors that significantly improved survival when combined with whole-brain radiation therapy (WBRT):

Karnofsky Performance Scale (KPS) >60: This indicates a higher level of functionality and overall health.
Intrathecal (IT) Chemotherapy: Direct delivery of chemotherapy into the cerebrospinal fluid.
Systemic Therapy: Use of drugs to target cancer cells throughout the body.
Hormonal Receptor Status: The presence of hormone receptors on cancer cells, which can be targeted with specific therapies.
Severity of Systemic Disease: Less extensive spread of cancer throughout the body.

Patients who met these criteria and received WBRT experienced a median survival of 17 weeks, compared to 11.9 weeks for those who did not (P = 0.015), indicating a significant survival advantage. Similarly, ten studies focused on non-small cell lung cancer (NSCLC)-caused LMC, identifying IT chemotherapy, KPS > 60, and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) treatment as beneficial factors. Patients meeting these criteria had a longer median survival when treated with WBRT (17.6 weeks vs 12.2 weeks, p = 0.0412).

Improving Outcomes for LMC Patients

This review underscores the importance of carefully assessing patient profiles to determine who will benefit most from radiation therapy. While RT plays a crucial role in managing LMC, its effectiveness is significantly influenced by factors such as the patient’s overall health, the extent of systemic disease, and specific treatments received. By identifying these key indicators, clinicians can better tailor treatment plans, improving survival rates and quality of life for patients with leptomeningeal carcinomatosis.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1002/pro6.43, Alternate LINK

Title: Examining The Survival Benefit Of Radiation Therapy On Leptomeningeal Carcinomatosis And Identifying Factors Associated With Survival Benefit Of Whole-Brain Radiation Therapy

Subject: Oncology

Journal: Precision Radiation Oncology

Publisher: Wiley

Authors: Jae Kim

Published: 2018-06-01

Everything You Need To Know

What is Leptomeningeal carcinomatosis, and why is it important?

Leptomeningeal carcinomatosis (LMC) is a severe condition where cancer spreads to the membranes around the brain and spinal cord. It affects approximately 5% of cancer patients and disrupts the central nervous system. Its impact includes neurological issues and, without treatment, a short median survival of 4-6 weeks. This is significant because it highlights the aggressive nature of the cancer spread and the critical need for interventions like radiation therapy (RT) and other treatments to improve outcomes.

What is the role of radiation therapy in treating Leptomeningeal carcinomatosis?

Radiation therapy (RT) is a treatment used to target specific sites and alleviate pressure caused by Leptomeningeal carcinomatosis (LMC). It is often used with intrathecal chemotherapy. While RT is a crucial component in managing LMC, it's important to note that its effectiveness isn't always conclusive due to LMC's poor prognosis. Research focuses on identifying which patients benefit most from RT to allow clinicians to tailor treatment plans to improve survival rates and quality of life for patients with Leptomeningeal carcinomatosis.

What factors influence the effectiveness of radiation therapy?

Several factors influence the success of radiation therapy (RT) for patients with Leptomeningeal carcinomatosis (LMC). For patients with primary breast cancer, a Karnofsky Performance Scale (KPS) >60, use of Intrathecal (IT) Chemotherapy, Systemic Therapy, positive Hormonal Receptor Status, and less severe Systemic Disease are crucial for survival improvement. For those with non-small cell lung cancer (NSCLC)-caused LMC, Intrathecal (IT) Chemotherapy, KPS > 60, and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) treatment were beneficial. These factors help determine which patients are most likely to benefit from Whole-Brain Radiation Therapy (WBRT).

How does the Karnofsky Performance Scale affect treatment outcomes?

The Karnofsky Performance Scale (KPS) measures a patient's ability to perform daily activities and their overall functional status. A KPS score >60 indicates better overall health and functionality. In the context of Leptomeningeal carcinomatosis (LMC), a higher KPS score is a key factor in determining which patients benefit most from radiation therapy (RT). Patients with a higher KPS score tend to have longer survival times when RT is combined with other treatments such as Intrathecal (IT) Chemotherapy, showing that patients with better overall health respond better to treatment.

What is Intrathecal chemotherapy, and why is it used for Leptomeningeal carcinomatosis?

Intrathecal (IT) chemotherapy involves directly delivering chemotherapy drugs into the cerebrospinal fluid (CSF) to treat cancer cells within the central nervous system. This method allows high concentrations of drugs to reach the cancer cells in the brain and spinal cord, which is crucial in managing Leptomeningeal carcinomatosis (LMC). When combined with radiation therapy (RT) and other therapies like Systemic Therapy, IT chemotherapy has been shown to significantly improve survival outcomes. Its importance lies in its ability to directly target cancer cells in the affected area, which is a key component of successful treatment for LMC.