Laser Interstitial Thermal Therapy Appears to be a Promising Option in New, Recurrent Glioblastoma

Interstitial thermal therapy (LITT) appeared to be a promising option for patients with new and recurrent glioblastoma, with a comparable median overall survival (OS) vs other resection studies using radiation and chemotherapy followed by laser ablation for those with IDH wild-type newly diagnosed glioblastoma vs recurrent disease, according findings from the multicenter LAANTERN study (NCT02392078) published in Neuro-Oncology Advances.

The median OS was 9.73 months (95% CI, 5.16-15.91) in patients who were newly diagnosed, with a median progression-free survival (PFS) of 5.92 months (95% CI, 3.65-not reached [NR]) Among recurrent patients, the median post-procedure survival was 8.97 months (95% CI, 6.94-12.36) and a median PFS of 4.83 months (95% CI, 3.02-5.82). In patients who were newly diagnosed and receiving chemotherapy and radiation within 12 weeks of LITT, the median OS was 16.14 months (95% CI, 6.11-NR).

The final analysis included total of 89 patients, 29 of whom were newly diagnosed and 60 had recurrent disease that was IDH wild-type glioblastoma. A total of 6.7% of recurrent patients were previously treated with LITT, 88.3% underwent resection, 86.7% received radiation, and 90% received chemotherapy. In those who were newly diagnosed, 53.8% began treatment with radiation and temozolomide (Temodal) followed by LITT, and 15.4% received bevacizumab (Avastin).

In 52% of patients who were newly diagnosed and 42% received LITT as their lesion was unresectable via traditional means. Moreover, 41% vs 42% of patients in each respective cohort opted for minimally invasive procedures. Investigators also reported that 59% vs 27% of those in the newly diagnosed and recurrent cohorts, respectively, had deep-seated tumors. By physician report, lesion volumes greater than 3 cc occurred in 51.6% of patients who were newly diagnosed vs 60.8% with recurrent disease. Additionally, thalamic lesions occurred in 17.6% vs 9.4%, respectively.

Of the patients with recurrent disease, 42 of 60 underwent intraoperative biopsy that highlighted 26 cases of tumor recurrence, 13 with mixed radiation necrosis, and 3 with radiation necrosis and no active tumor. In patients who were newly diagnosed, the mean surgical skin-to-skin time was 4.07 hours vs 3.29 hours in those with recurrent disease. Moreover, the median lase time was 26 minutes and 32 seconds vs 25 minutes and 8 seconds in the newly diagnosed and recurrent groups, respectively. The median post-procedure follow-up time was 268 days.

Evaluable laboratory analysis findings were available in 55% of patients overall. The median pre-ablation time tumor volume was 7.7 cc in the newly diagnosed group vs 8.5 cc in the recurrent groups, respectively. Seven patients who were newly diagnosed and 4 who were recurrent compared had sub-total ablations and 16 vs 22 who had total or supra-total ablations.

Patients spent a median of 50 hours in the hospital and 80% were discharged to go home. ICU stay post-procedure was necessary in 50% of patients. Of note, these findings were similar to other studies conducted with LITT in this patient population.

Karnofsky performance scale (KPS) was assessed in 60 patients at baseline and recorded. A total of 43.8% of patients who were newly diagnosed and 50% with recurrent disease had improved KPS over baseline at the 1-month follow-up, but the changes were not significant (P = .2502). At baseline for both groups, the median KPS was 90 and 80 at both 1-month and 3-months post-procedure time points.

Adverse effects (AEs) occurred in 13.5% of patients. The most commonly reported AEs were neurological deficit (5.6%) and edema (4.5%). Permanent aphasia that was mild to moderate was reported in 2.2% of patients, and 1.1% had permanent motor deficit following ablation of a right frontal lesion. Within 30 days of the procedure, 1 visual deficit and 1 motor deficit were resolved. Deep vein thrombosis was reported in 1 patient, and another had hemorrhaged. No patients died in relation to treatment.

Reference

de Groot JF, Kim AH, Prabhu S, et al. Efficacy of laser interstitial thermal therapy (LITT) for newly diagnosed and recurrent IDH wild-type glioblastoma. Neurooncol Adv. 2022;4(1):vdac040. Published 2022 Apr 6. doi:10.1093/noajnl/vdac040