Brain Metastases in Lung Cancer: Still Room to Personalize Care
http://cancergrace.org/lung/2011 ... o-personalize-care/
For non-small cell lung cancer patients with multiple brain metastases, the standard approach of whole brain radiotherapy is not necessarily standard for each and every patient. Each patient’s specific situation may sometimes be best approached with various combinations of surgery, radiation, medical/systemic therapy, and non-cancer directed treatment.
The best course of treatment depends on many factors. Key aspects of a patient’s situation include age, how well the patient is doing in general, whether they have other sites of metastasis other than the brain (and whether those sites harbor active cancer), how extensive the brain metastases are in size and number, and whether they are experiencing symptoms.
Symptoms are often caused by swelling in and around the brain metastasis which then compresses the normal healthy brain. Steroid medication such as dexamethasone is helpful in reducing such swelling. In some situations, surgical decompression can dramatically relieve swelling, and accomplish relief of edema quickly. Indeed, this is one of the great benefits of surgery in the setting of multiple brain metastases.
In general, for patients with more extensive intracranial and extracranial disease, whole brain irradiation offers broad regional control of brain metastases – by itself or following surgical resection brain lesion(s). In the short term, whole brain radiotherapy can cause hair loss, headache, fatigue, nausea, and Eustachian tube dysfunction. In the long term, the greatest side effects are upon short term memory and the ability to multitask.
An alternative to whole brain irradiation in some circumstances is stereotactic radiosurgery – a focused approach targeting known areas of brain metastases. Stereotactic radiosurgery can be accomplished with multiple devices – Gamma Knife and Cyberknife are examples of dedicated stereotactic radiosurgery platforms. For patients that present with a solitary or limited brain metastasis, there is a fifty percent chance they will develop other brain metastases and may eventually benefit from whole brain irradiation. There does not seem to be a detriment to initially deferring whole brain irradiation in favor of stereotactic radiotherapy for these patients. For patients with more extensive brain metastases, the risk of developing additional brain metastases is likely higher.
Where exactly the line is drawn between “limited” vs. “more extensive” brain metastases is not clear. In some studies, patients with up to 3 or 4 brain metastases were considered to have “limited disease.” For patients with more extensive metastatic brain disease, consideration of stereotactic radiosurgery as an alternative to whole brain irradiation or in addition to whole brain radiation revolves around assessment of the tempo of the cancer and the patient’s general fitness. In circumstances where the cancer is generally otherwise controlled and the patient is otherwise fit, healthy, and active, it is reasonable to lead treatment with a stereotactic approach and reserve whole brain irradiation, or to perhaps lead with whole brain irradiation with consideration of using stereotactic radiosurgery to control dominant lesion.
In the context of radiosurgery, careful monitoring for additional metastases is often emphasized. I agree, however, I also recommend that for patients otherwise generally doing well, that I also would monitor the brain with subsequent MRIs after whole brain irradiation. Even after whole brain irradiation, there remains about a one-in-four chance of developing new metastases.
In situations where patients have active disease otherwise, stereotactic radiosurgery may sometimes be used to rapidly accomplish treatment prior to starting systemic therapy – stereotactic radiosurgery is often accomplished in a single half-day, as opposed to the multi-week schedule typical of whole brain irradiation. In this circumstance as well, stereotactic radiotherapy can enable deferment of potential whole brain associated side effects.
All of these decisions and considerations are of course made importantly in the context of a patient’s goals, and their circumstance. For patients suffering from extensive disease from which they are likely to succumb in the near term, whole brain irradiation followed by symptom directed medical and non-medical therapy is often the best plan.
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