Management of Skull Base Tumor-Associated Facial Pain

Superior orbital fissure narrowing and tumor-associated pain in spheno-orbital meningiomas

INTRODUCTION

Spheno-orbital meningiomas (SOMs) represent a distinct subtype of meningioma characterized by their unique multi-compartmental invasion pattern. Previous studies have investigated correlations between SOMs and visual manifestations. However, our comprehension of pain associated with SOMs remains limited. This study aims to provide insight into the pathophysiology underlying SOM-related pain through measurements of tumor volume and superior orbital fissure (SOF) narrowing.

METHODS

This retrospective study included patients who underwent surgical resection of a SOM between 2000 and 2022. Preoperative CT and/or MRI scans were analyzed, and the tumor volume of each segment was measured. Bony 3D reconstructions were used to measure the area of the SOF, and SOF narrowing was calculated.

RESULTS

The study cohort included 66 patients diagnosed with SOMs, among which 25.8% (n = 17) presented with pain. Postoperatively, 14/17 (82.4%) of patients reported pain improvement. There was no significant correlation between the total volume or the volume of tumor within each compartment and the presence of pain on presentation (p > 0.05). The median SOF narrowing was significantly different between patients presenting with and without tumor-associated pain with median of 11 mm2 (IQR 2.8-22.3) and 2 mm2 (IQR 0-6), respectively (p = 0.005). Using logistic regression, a significant correlation between the degree of SOF narrowing and the presence of SOM-associated pain on presentation was identified, with an aOR of 1.2 (95% CI 1.12-1.3, p = 0.02).

CONCLUSION

While the exact cause of tumor-associated pain remains unclear, SOF narrowing seems to play a role in pain among SOM patients. Based on the radiological characteristics, SOF neurovascular decompression is recommended in SOM patients.

A rare case of vestibular schwannoma manifesting as trigeminal neuralgia

BACKGROUND

In this case report, the authors reviewed a rare case of a vestibular schwannoma manifesting as trigeminal neuralgia (TN). Intracranial tumors can have a variety of orofacial pain symptoms. Among benign cerebellopontine angle tumors, vestibular schwannoma is the most common cause of a TN-like manifestation. Although the most common symptoms of a vestibular schwannoma are hearing loss and vestibulopathy, the unique feature of this case was the manifestation of symptoms consistent with TN.

CASE DESCRIPTION

The patient had right-sided episodic facial pain that was short in duration and severe in intensity. The initial differential diagnoses included short-lasting, unilateral, neuralgiform headache attacks with conjunctival injection and tearing and TN. As part of the routine evaluation, the patient was referred for brain magnetic resonance imaging, which revealed a right-sided vestibular schwannoma. The patient was prescribed 200 mg of gabapentin 3 times daily and was referred to neurosurgery for excision of the schwannoma. Surgical excision resulted in complete resolution of pain.

PRACTICAL IMPLICATIONS

This case illustrates the importance of interdisciplinary treatment and how it can lead to an optimal outcome for a patient with complex orofacial pain symptoms.

Computed tomography-guided Gasserian ganglion interventions for cancer-related facial pain in patients with complex anatomy: insights and recommendations

BACKGROUND

The Gasserian ganglion is a well-known target for facial pain management, and patients with cancer present an anatomical challenge owing to tumor progression or treatment itself. Computed tomography (CT) is an alternative method for guiding these procedures.

METHODS

This was an observational retrospective analysis of patients with cancer-related facial pain who underwent CT-guided Gasserian ganglion interventions using local anesthetics, local anesthetics with steroids, phenol, and radiofrequency. Demographic, clinical, and procedure-related variables were collected from January 1, 2015, to December 30, 2018, at the National Cancer Institute. Data distribution was determined using the Kolmogorov-Smirnov test. A paired sample t-test (with a cut-off of P < 0.05 for statistical significance) was used for comparing outcome.

RESULTS

We observed a significant reduction in numerical rating scale (NRS) and douleur neuropathique 4 (DN4) scores from 7.6 ± 1.4 and 4.4 ± 1.4 to 3.2 ± 2.0 and 2.2 ± 1.4 points, respectively (P < 0.001). After the procedure, 70.8% of the patients were satisfied; 16.7% were very satisfied, and 12.5% were unsatisfied. No intra- or postoperative complications were observed. The most common neoplasms were head and neck tumors (83.3%).

CONCLUSIONS

Our data suggest that CT guidance is an effective and safe option for managing cancer-related facial pain in patients with complex anatomy, resulting in a significant reduction in pain, high satisfaction rates, and no mechanical complications. Future research should aim to refine the role of CT guidance in multimodal pain management in this population.

Seeding of breast cancer cell line (MDA-MB-231LUC+) to the mandible induces overexpression of substance P and CGRP throughout the trigeminal ganglion and widespread peripheral sensory neuropathy throughout all three of its divisions

Some types of cancer are commonly associated with intense pain even at the early stages of the disease. The mandible is particularly vulnerable to metastasis from breast cancer, and this process has been studied using a bioluminescent human breast cancer cell line (MDA-MB-231^LUC+). Using this cell line and anatomic and neurophysiologic methods in the trigeminal ganglion (TG), we examined the impact of cancer seeding in the mandible on behavioral evidence of hypersensitivity and on trigeminal sensory neurons. Growth of cancer cells seeded to the mandible after arterial injection of the breast cancer cell line in Foxn1 animals (allogeneic model) induced behavioral hypersensitivity to mechanical stimulation of the whisker pad and desensitization of tactile and sensitization of nociceptive mechanically sensitive afferents. These changes were not restricted to the site of metastasis but extended to sensory afferents in all three divisions of the TG, accompanied by widespread overexpression of substance P and CGRP in neurons through the ganglion. Subcutaneous injection of supernatant from the MDA-MB-231^LUC+ cell culture in normal animals mimicked some of the changes in mechanically responsive afferents observed with mandibular metastasis. We conclude that released products from these cancer cells in the mandible are critical for the development of cancer-induced pain and that the overall response of the system greatly surpasses these local effects, consistent with the widespread distribution of pain in patients. The mechanisms of neuronal plasticity likely occur in the TG itself and are not restricted to afferents exposed to the metastatic cancer microenvironment.