Treatment of Leptomeningeal Metastases in a Patient with Non-Small Cell Lung Cancer Harboring EGFR T790M Mutation.

BACKGROUND: Leptomeningeal metastasis (LM) is an uncommon complication in patients with solid tumors, associated with poor survival. However, LM appears to be more frequent in lung cancer patients with EGFR mutations, posing a unique clinical challenge to treating physicians. CASE PRESENTATION: We report the case of a 68-year-old Asian man with metastatic lung adenocarcinoma harboring an EGFR L858R mutation, which was initially treated with gefitinib. He developed disease progression 1 year later. Re-biopsy of the right lower lobe primary lesion revealed only an EGFR L858R mutation in the absence of a T790M mutation. The patient also experienced persistent confusion and generalized fatigue, and magnetic resonance imaging (MRI) of the brain demonstrated extensive LM. At this time, a liquid biopsy revealed an EGFR T790M mutation. Following initiation of treatment with osimertinib, the patient exhibited a rapid response with MRI of the brain showing substantial improvement of the LM after 6 months. Unfortunately, the LM recurred after 1 year at which time the patient declined further systemic chemotherapy. CONCLUSION: To our knowledge, this is the second reported case of LM in a patient with lung cancer harboring an EGFR T790M mutation that was successfully treated with osimertinib.

Normobaric oxygen therapy strategies in the treatment of postcraniotomy pneumocephalus.

OBJECT: Postsurgical pneumocephalus is an unavoidable sequela of craniotomy. Sufficiently large volumes of intracranial air can cause headaches, lethargy, and neurological deficits. Supplemental O(2) to increase the rate of absorption of intracranial air is a common but unsubstantiated neurosurgical practice. To the authors' knowledge, this is the first prospective study to examine the efficacy of this therapy and its effect on the rate of pneumocephalus absorption. METHODS: Thirteen patients with postoperative pneumocephalus that was estimated to be > or = 30 ml were alternately assigned to breathe 100% O(2) using a nonrebreather mask (treatment group) or to breathe room air (control group) for 24 hours. Head computed tomography (CT) scans without contrast enhancement were obtained at the beginning and end of treatment or control therapy. A neuroradiologist blinded to the type of treatment used software to calculate the 3D volume of the pneumocephalus from the CT scans. The percentage of pneumocephalus absorption was calculated for each study participant. RESULTS: There was no statistically significant difference between the treatment and control groups regarding the mean initial pneumocephalus volume or time interval between CT scans. There was a significant difference (p = 0.009) between the mean rate of pneumocephalus volume reduction in the treatment (65%) and control groups (31%) per 24 hours. No patient suffered adverse effects related to treatment. CONCLUSIONS: Administration of postsurgical supplemental O(2) through a nonrebreather mask significantly increases the absorption rate of postcraniotomy pneumocephalus as compared with breathing room air.