Stereotactic radiotherapy using Novalis for skull base metastases developing with cranial nerve symptoms

Abstract

Skull base metastases are challenging situations because they often involve critical structures such as cranial nerves. We evaluated the role of stereotactic radiotherapy (SRT) which can give high doses to the tumors sparing normal structures. We treated 11 cases of skull base metastases from other visceral carcinomas. They had neurological symptoms due to cranial nerve involvement including optic nerve (3 patients), oculomotor (3), trigeminal (6), abducens (1), facial (4), acoustic (1), and lower cranial nerves (1). The interval between the onset of cranial nerve symptoms and Novalis SRT was 1 week to 7 months. Eleven tumors of 8-112 ml in volume were treated by Novalis SRT with 30-50 Gy in 10-14 fractions. The tumors were covered by 90-95% isodose. Imaging and clinical follow-up has been obtained in all 11 patients for 5-36 months after SRT. Seven patients among 11 died from primary carcinoma or other visceral metastases 9-36 months after Novalis SRT. All 11 metastatic tumors were locally controlled until the end of the follow-up time or patient death, though retreatment for re-growth was done in 1 patient. In 10 of 11 patients, cranial nerve deficits were improved completely or partially. In some patients, the cranial nerve symptoms were relieved even during the period of fractionated SRT. Novalis SRT is thought to be safe and effective treatment for skull base metastases with involvement of cranial nerves and it may improve cranial nerve symptoms quickly.

Survival and Recurrence for Patients Undergoing Surgery of Skull Base Intracranial Metastases

“…[10][11][12] In this study, 29 (4%) patients underwent surgery for a SBM during the reviewed period.…”

“…[10][11][12] Patients with SBM are typically only offered radiation therapy in the form of stereotactic radiosurgery, whole-brain radiation, or proton beam therapy. 6,10-13 Surgical interventions are withheld because the surgical outcomes for patients with SBM remain unclear.…”

Solitary Skull Metastases from Breast Carcinoma

“…Localized radiotherapy or stereotactic radiotherapy is also benefi cial in multiple inoperable cases or in those with skull base metastases. 6,7 Chemotherapy is targeted for the primary tumor and recent Phase I studies have shown some benefi t of Temozolamide alone or in combination with capecitabine is a well-tolerated regimen even in breast metastases. [8][9][10][11] A combination oral VRL plus capecitabine is anotherPhase II trial safe regimen used in cases which have already been treated with chemotherapy.…”

Metastatic lung cancer presenting with jugular foramen syndrome in a case of von Recklinghausens disease

“…[12] Postoperative radiotherapy is used to control the residual disease, where there is subtotal removal either to preserve the cranial nerve functions, vital vascular structures, and the brainstem. [13,14] Novalis stereotactic radiotherapy (SRT) has been used in high doses (30-50 Gy in 10-14 fractions) as a safe and effective treatment modality to treat skull base metastases from visceral carcinomas with sparing of normal structures and it was shown that in majority of the patients cranial nerve deficits were improved either completely or partially. [14] Because of the non-availability and non-affordability, fractionated stereotactic radiotherapy (FSRT) or stereotactic radiosurgery (SRS) could not be offered to the patient as noninvasive treatment alternatives to microsurgery either for the primary control of the disease or for control of post-operative pain.…”