**9. Use of LITT in cancer-related pain**

**8. Use of LITT in other intracranial tumors**

diameter treated was 7.0± 9.0 cm3

298 Neurooncology - Newer Developments

of the procedure.

Jethwa et al. [63] reported the application of Visualase laser system in 20 patients (33 proce‐ dures) with a variety ofintracranial tumors over a period of 1 year. GBM was the most common pathology treated (*n* = 6), followed by metastasis (*n* = 4), ependymoma (*n* = 3), meningioma (*n* = 2), hemangioblastoma (*n* = 2), anaplastic astrocytoma (*n* = 1), chordoma (*n* = 1) and supratentotrial primitive neuroectodermal tumor (*n* = 1) in this study. LITT was considered primarily in patients with failed priortreatment (10 out of 20), in surgically inaccessible areas (*n* = 3), patient preference (*n* = 3) or in those in who conventional surgery was considered high risk (*n* = 4) [63]. Majority of patients were treated with single laser application; however, two patients with GBM, one each with metastasis, meningioma, ependymoma underwent two applications and one patient with GBM required three laser applications to cover the tumor volume. One patient each with ependymoma and GBM underwent staged LITT procedure 2 months apart and one with supratentotrial primitive neuroectodermal tumor underwent repeat procedure due to tumor recurrence. The average tumor volume and average tumor

min and median hospital stay of 24 h (average stay of 2.27 days) in this study [63]. It was noted in the study that LITT was welltolerated in the majority of patients with four procedure-related complications. Inaccurate placement of laser probe (patient with cerebellum hemangioblasto‐ ma), placement-related hemorrhage (nearright sylvian fissure meningioma), pituitary thermal injury (pediatric patient with third ventricle recurrent ependymoma) and significant peripro‐ cedural edema (patient with GBM) were reported following 33 LITT procedures in 20 patients. All these complications except pituitary thermal injury required open surgical procedure. Tumor control rates and follow-up imaging were not reported in this study. Another group reported the use of LITT in six patients with intracranial tumors (metastasis, *n* = 4; pituitary prolactinoma, *n* = 1; medullary ependymoma) and one patient with conus ependymoma [129]. Complete ablation was achieved in six out of seven patients and no procedure-related adverse effects were noted in these patients [129]. No long-term outcomes and follow-up results were reported following LITT forthese tumors. Recently, Patel et al. [98] reported the utility of LITT using Visualase system in patients with a variety of intracranial tumors such as meningioma (*n* = 2), ependymoma (*n* = 3), hemangioblastoma (*n* = 2), primitive neuroectodermal tumor (*n* = 3), cavernoma (*n* = 2), chordoma (*n* = 1), teratoma (*n* = 1), CNS lymphoma (*n* = 1) and pineal tumor (*n* = 1) [98]. Total operative time and ablation time were 2.8±0.6 hrs and 8.7±8.1 mins, respectively, in all patients with intracranial tumors including glial tumors (GBM, ganglio‐ glioma, pilocytic astrocytoma). Postoperative complications such as neurological worsening (*n* = 7), hemorrhage (*n* = 2), edema (*n* = 4), infection (*n* = 1), inaccurate catheter placement (*n* = 2) and two deaths following LITT were reported [98]. A major limitation of this study was that outcomes including tumor control rates and recurrence were not reported in this study [98]. The procedure was not completed in two patients, one with recurrent meningioma due to hemorrhage during probe insertion which required emergent evacuation and the second patient with hemangioblastoma had inaccurate placement of laser probe which led to abortion

and 2.4± 0.85 cm. The average ablation time was 13.9± 10.7

Cancer-related pain is a significant clinical problem affecting up to 60–90% of patients with cancer in terminal stages [130]. The first line of management in such patients is pharmacolog‐ ical including opioids; however, 10–20% of such patients are refractory to medical line of management and thus requires intervention for pain management [131–133]. Various neuromodulation and ablative procedures such as intrathecal morphine, myelotomy, cordotomy, DREZotomy, sympathetic blocks, paravertebral blocks and cingulotomy have been described for pharmacological-resistant, cancer-related and various refractory pain syndromes [131–137]. Ablative cingulotomy using radiofrequency [136] and neuromodula‐ tion using DBS [138] has been described in patients with various refractory pain syndromes. With the advances in neuroimaging and stereotactic techniques and introduction of LITT, this technique has been explored in patients with pharmacoresistant cancer-related pain [12, 98]. Patel et al. [12] describe the feasibility of MRgLITT in three patients (four procedures) with cancer-related pain. Ablation coordinates used in patients who underwent first-time abla‐ tion includes *x* = 7.9 mm (6.9–8.6mm range); *y* = 20.5 mm (20–22 mm range); *Z* = 6.9 mm (2.9– 7.0 mm) above the lateral ventricles. Second ablation 1–2 cm above the first ablation was performed in patients with first-time ablation procedures. One patient who underwent ablation for recurrence had three ablations. Median ablation time and volume ablated were 257 seconds and 1.5 cm3 , respectively. Median pain severity score (PSS) decreased from 7.7 in preoperative period to 1.6 following the LITT procedure. Similarly, pain interference score (PIS) decreased from 9.9 to 2.0 following the procedure [12]. Median pain reduction was maintained for 5 weeks (2–16 weeks) following LITT and all patients had significant reduc‐ tion in medication requirements during the period. No significant adverse effects related to the procedure were noted in this study. The advantage of LITT is that the ablation can be monitored in real-time using MR thermography, which was not feasible in earlier ablative techniques.

Another recent study reported the utility of LITT in five patients with chronic pain syn‐ drome [98]. Total operative time and ablation time were 2.9±0.3 h and 4.3±0.6 mins, respec‐ tively. No postoperative complications were noted following LITT in patients with chronic pain [98]. Outcomes in terms of pain control was not reported in this study [98].
