A 75-year-old man was diagnosed in June 2016 with right-sided pleural desmoplastic mesothelioma. He had a previous history of smoking and exposure to asbestos as well as substantial underlying cardiovascular comorbidity. Curative treatment was deemed not feasible. While awaiting palliative antitumoral treatment, the patient experienced impaired balance, severe rotational vertigo, nausea, and vomiting. Brain CT and MRI in July 2016 revealed a solitary 20-mm metastasis with slight surrounding edema in the left middle cerebellar peduncle and extending along the tentorium (M1). V4 was minimally compressed without hydrocephalus. Corticosteroid therapy was initiated but microsurgery was deemed not feasible due to previous cardiovascular morbidity. Systemic palliative chemotherapy was initiated and he was referred for GKRS as no other treatment options remained available for M1. The patient underwent 3R-intervention for his solitary lesion in August 2016. KPS was estimated as 70–80 and RPA as 2 at GKRS 1 during steroid treatment de-escalation. KPS subsequently improved to 80 at GKRS 2 and 90–100 at GKRS 3 despite decreased steroid dose. M1 underwent a volume reduction of 22% between GKRS 1 and GKRS 3 (10.2 cm3 to 7.9 cm3) while V4 volume increased from 0.79 cm3 to 0.93 cm3 (21%). One-month follow-up with clinical assessment and MRI revealed mild fatigue presumed due to ongoing systemic antitumoral treatment (KPS 90) though without major neurological impairment, and substantial tumor volume reduction of almost 50% (10.2 cm3 at GKRS 1 to 5.6 cm3 at 4 weeks after GKRS 3). V4 volume had also increased significantly (from 0.79 cm3 at GKRS 1 to 1.31 cm3 at 4 weeks) []. A follow-up MRI at 3 months showed a small suspected recurrence with mild surrounding edema at the inferior aspect of the previous radiation field which was successfully treated in December 2016 along with ten new metastases; all eleven lesions were treated with SF-GKRS. No clinical signs of neurological deficits or radiological evidence of ARE were reported. The patient died 6 months after completion of 3R due to an aggressive, drug-resistant pneumonia.
A 72-year-old male presented to his family doctor with a 3 week history of headache and dizziness. His medical history was unremarkable except for left-sided nephrectomy for clear cell renal cell cancer stage T2 N0 M0 8 years earlier. Diagnostic imaging with brain computed tomography (CT) scan followed by magnetic resonance imaging (MRI) revealed a 3 cm large contrast-enhancing infratentorial tumor (Figure ). No additional brain lesions were detected. CT of chest and abdomen revealed 2 small lung nodules (one left-sided, one right-sided) and enlarged mediastinal lymph nodes (Figure ). Neurosurgical resection of the intracranial tumor confirmed metastasis from clear cell carcinoma. Neither postoperative radiotherapy nor systemic treatment was recommended at this time. Surveillance CT scans showed very slow enlargement of the lung and lymph node metastases during the next year. Seventeen months after resection of the cerebellar metastasis, local recurrence was detected. The patient was treated with gamma knife SRS (peripheral dose 21 Gy). Six months later, a single new brain metastasis was found (8 mm large, left occipital lobe), which also was treated with SRS. Seven months after the second SRS procedure, a third one was added after diagnosis of two new infratentorial brain lesions (cerebellum and brain stem, respectively). Treatment planning MRI also revealed a contrast-enhancing extramedullary mass at the level of the 5th cervical vertebra. Additional scans of the spine showed at least two more small metastases in the lower thoracic and upper lumbar region (Figure ). No cerebrospinal fluid (CSF) examination was performed as imaging and history were consistent with a diagnosis of NM. The involved regions were treated with fractionated external beam radiotherapy (10 fractions of 3.5 Gy). At that time, the patient had a Karnofsky performance status (KPS) of 70. He had no new focal neurologic deficits, but continued to experience dizziness and gait disturbance since his first SRS procedure. Because of intense pain in different skeletal regions, a radioisotope bone scan was performed, which showed bone metastases in the corresponding areas. These metastases were confirmed by radiographs and/or CT. Analgetic treatment with opiods was started and external beam radiotherapy fields were added to parts of the pelvis, femur and shoulder. For the first time during follow-up, elevated lactate dehydrogenase levels (266 U/L) and lymphopenia (0.3 × 109/L) were seen. The known lung and lymph node lesions continued to progress slowly (Figure ). Three weeks after radiotherapy, the first systemic treatment was initiated, consisting of sunitinib 50 mg per day. After two weeks on sunitinib, the patient presented to the emergency room with chills and reduced general condition. Fever (38.7°C), elevated C-reactive protein (CRP) level (235 mg/L), leukopenia (3.2 × 109/L) and thrombopenia (73 × 109/L) were found. Blood- and urine cultures were negative. Chest X-ray showed a small infiltrate. Sunitinib treatment was stopped and antibiotic therapy initiated. The patient recovered, but was still unable to reduce analgesics and had a KPS of 50. The treating oncologists decided to stop active cancer treatment. Three weeks later, he began to lose strength in the lower extremities. Steroid treatment was unsuccessful. Imaging was not repeated as management would not have been altered. Another three weeks later, the patient again presented to the emergency room with chest pain, dyspnea and tachycardia. Chest X-ray revealed pneumonia, CRP was elevated to 228 mg/L, leukocyte counts normal (6.6 × 109/L). In spite of antibiotic treatment, the patient succumbed to his disease a few hours after admission. Survival was 11 years from nephrectomy, 35 months from initial diagnosis of brain and lung metastases, and 4 months from NM and bone metastases.