Israel Medical Association Journal

Background: Prophylactic cranial irradiation (PCI) exclusion in favor of brain magnetic resonance imaging (MRI) staging and surveillance in the management of small cell lung cancer (SCLC) is controversial yet accepted by some centers. The use of MRI suggests performing stereotactic radiosurgery (SRS) treatment for limited brain metastases. Data regarding SRS efficacy in this setting is limited.

Objectives: To assess intracranial objective response rate (iORR), progression-free survival (iPFS), intracranial failure patterns, overall survival (OS) and time-to-whole-brain radiation therapy (WBRT)/death, whichever occurred first (TTWD) with SRS in SCLC.

Methods: The study comprised 10 consecutive SCLC patients with brain metastases treated with SRS and followed-up at Davidoff Cancer center between Aug 2012 and March 2019. Brain MRI images were reviewed by a neuro-radiology specialist.

Results: iORR was 57% as assessed by response assessment in neuro-oncology brain metastases. Intracranial progression developed in 8 patients. Median iPFS was 4.0 months (95% confidence interval [95%CI] 1.7–7.2). In-site, off-site and combined pattern of intracranial failure was seen in 0, 5, and 3 patients, respectively; median number of new brain lesions following SRS was 4 (range, 1–12). SRS was performed 10 additional times in 6 patients (median number of lesions irradiated per round was 1, range 1–5). WBRT was administered in 3 patients. Median TTWD was 20.9 months (95% CI, 1.9–26.8). Median OS since SRS administration was 23.2 months (95% CI, 4.2–not reached).

Conclusions: MRI surveillance with multiple rounds of SRS may serve a reasonable alternative to PCI or therapeutic WBRT in SCLC. 

Objectives: To evaluate the safety and applicability of the Elekta Synergy-S radiation unit for the treatment of spinal tumors.

Methods: We retrospectively reviewed all patients treated with stereotactic radiosurgery to spinal tumors between November 2007 and June 2011.

Results: Thirty-four patients were treated for 41 lesions. Treatment indications were local tumor control and pain palliation. The mean follow-up was 10.8 ± 11.6 months (range 0.5–38 months). No acute radiation toxicity or new neurological deficits occurred during the follow-up period. Local tumor control was achieved in 21 of the 24 lesions (87.5%) available for radiological follow-up at a median of 9.8 months (range 3–32 months). Good analgesia was achieved in 24/30 lesions (80%) that presented with intractable pain.

Conclusions: The safety and feasibility of delivering single and multiple-fraction stereotactic spinal irradiation was demonstrated and became a standard treatment option in our institution. 

Objectives: To report the experience at the first Israeli Linear Accelerator Radiosurgery Unit in the management of 44 patients with acoustic neurinomas.

Methods: We analyzed the clinical records and imaging studies of all patients undergoing radiosurgery for acoustic neurinomas between 1993 and 1997, and quanitified the changes in tumor volume, hearing status, and facial and trigeminal nerve function. The contribution of radiation dose and original tumor volume upon those variables was also studied.

Results: At a mean follow-up of 32 months (range 12–60), 98% of the tumors were controlled (75% had shrunk; 23% had stable volume). The actuarial hearing preservation rate was 71%. New transient facial neuropathy developed in 24% of the patients, persisting in mild degrees in 8%. Neuropathy correlated primarily with tumor volume. Tumors with volumes 4 ml were at high risk when marginal radiation doses were 1,400 cGy. Dose reduction to a maximum of 1,400 cGy produced no neuropathies in the last 20 patients, still preserving tumor control rates.

Conclusions: Radiosurgery is an effective and cost-efficient therapeutic modality for newly diagnosed acoustic neurinomas in the elderly or medically infirm population, and for all residual or recurrent tumors after conventional surgery.