# Treatment decisions for intermediate-sized brain metastases in or near the motor cortex among the neuro-oncology community

## TL;DR

This study explores treatment preferences for brain tumors near the motor cortex among Dutch neuro-oncology specialists.

## Contribution

The paper identifies key factors influencing treatment decisions and highlights a lack of consensus among specialists.

## Key findings

- Treatment decisions are influenced by tumor size, neurological deficits, and immunotherapy use.
- A median cutoff size of 35 mm is suggested for surgery.
- Neurosurgeons prefer surgery for smaller tumors compared to radiation oncologists.

## Abstract

Currently, there is lack of consensus regarding the optimal treatment strategy (surgery versus radiotherapy) for intermediate-sized (2–4 cm) brain metastases (BM), especially those located in or near the motor cortex. This survey aims to gain insight into treatment decisions for these BM among the Dutch multidisciplinary neuro-oncology community.

An electronic survey was distributed among neurosurgeons, radiation oncologists, neurologists, and medical oncologists in The Netherlands. The survey comprised 13 questions regarding physician's practices and questions about treatment decisions for BM in or near the motor cortex using statements and three theoretical patient cases.

Tumor size (n = 34, 89 %), degree of neurological deficit (n = 31, 82 %), and the need for (temporarily) discontinuation of immunotherapy because of dexamethasone dependence (n = 30, 79 %) were highlighted as the most important factors to steer the treatment decision to radiotherapy or surgery. When divided by specialty, 15 neurologists (33 %), 14 radiation oncologists (30 %), 12 neurosurgeons (26 %), and 5 medical oncologists (11 %), some variability about the importance of factors exists. The respondents suggested a median cutoff size of 3,5 cm for conducting surgery on BM.

Surgical resection is preferred in patients with larger tumors, with neurologic symptoms that are unresponsive to dexamethasone, and in patients receiving immunotherapy. Future investigations should compare the effectiveness of surgical resection and stereotactic radiosurgery, and the effects on survival and quality of life in patients with BM in or near the motor cortex in a prospective and preferable randomized manner.

•Treatment choices for BM near the motor cortex vary among specialists.•Tumor size, neurological deficits, and immunotherapy use impact decision-making.•A median cutoff size of 35 mm was suggested by respondents for conducting surgery.•Neurosurgeons prefer surgery for smaller BM than radiation-oncologists (20 vs 35 mm).•A lack of consensus highlights the need for randomized studies on treatment efficacy.

Treatment choices for BM near the motor cortex vary among specialists.

Tumor size, neurological deficits, and immunotherapy use impact decision-making.

A median cutoff size of 35 mm was suggested by respondents for conducting surgery.

Neurosurgeons prefer surgery for smaller BM than radiation-oncologists (20 vs 35 mm).

A lack of consensus highlights the need for randomized studies on treatment efficacy.