Long term outcomes with linear accelerator stereotactic radiosurgery for treatment of jugulotympanic paragangliomas

Debulking surgery prior to stereotactic radiotherapy for head and neck paragangliomas

Background

Surgery has been used as standard treatment for head and neck paragangliomas. Stereotactic radiotherapy (SRT) has also been increasingly used for this disease. The results for combined modality are not well described. This analysis aims to describe the results for combined modality of debulking surgery and SRT for head and neck paragangliomas (HNP).

Materials and and methods

Retrospective cohort of patients treated in a large university hospital between 2008 and 2023.

Results

Fifty-one patients had their charts reviewed. Mean age was 56.3 years. Most were female (82.3%). Most lesions arose from the skull-base (84.3%) and not the inner ear. Most lesions were larger than 3 cm (51.0%) and mean lesion size was 4.4 cm. 36 (70.6%) were treated with radiotherapy alone while 15 (29.4%) were treated with combined modality treatment. Median follow-up was 42.5 months (7.1-112.8 months). There were no reported deaths nor disease progression. Debulking surgery did not impact response rate for SRT (52.8% vs. 47.2% for SRT alone and debulking surgery, respectively, p = 0.971). There was no impact on new neurological deficits after SRT (25.0 vs. 13.3%, respectively, p = 0.356).

Conclusion

Debulking surgery did not improve response rate for SRT. In our sample, it also did not impact new neurological deficits for SRT. Prospective data regarding HNP treatment is needed.

A single-session stereotactic radiosurgery for vagal paraganglioma: Effective tumor reduction and innovative treatment option

Background

Vagal paragangliomas (VPs) are rare tumors in the upper cervical region. Although surgical resection is the standard treatment for these tumors, it carries significant risks due to the tumor's high vascularity and proximity to vital structures. Stereotactic radiosurgery (SRS) for skull base paraganglioma could be a minimally invasive alternative.

Case Description

We report the case of a 47-year-old man with a large, asymptomatic VP who was successfully treated with SRS with Gamma Knife Icon, which was performed in the parapharyngeal space (volume: 25.7 mL) using a marginal dose of 14 Gy to the 45% isodose line. This case illustrates the successful treatment of a lesion near the conventional limits (lower limit of C2 vertebral body) using noninvasive mask fixation. Excellent tumor control without neurological deficits was achieved for 25 months after SRS. The tumor volume decreased by 70% (final volume: 7.6 mL).

Conclusion

This study demonstrates the utility of Gamma Knife Icon, which facilitates optimal SRS for upper cervical lesions, including VPs.

Approach to the Patient: Concept and Application of Targeted Radiotherapy in the Paraganglioma Patient

Paragangliomas can metastasize, posing potential challenges both in symptomatic management and disease control. Systemic targeted radiotherapies using 131I-MIBG and 177Lu-DOTATATE are a mainstay in the treatment of metastatic paragangliomas. This clinical scenario and discussion aim to enhance physicians' knowledge of the stepwise approach to treat these patients with paraganglioma-targeted radiotherapies. It comprehensively discusses current approaches to selecting paraganglioma patients for targeted radiotherapies and how to choose between the two radiotherapies based on specific patient and tumor characteristics, when either therapy is feasible, or one is superior to another. The safety, efficacy, toxicity profiles, and optimization of these radiotherapies are also discussed, along with other therapeutic options including radiotherapies, available for patients besides these two therapies. Perspectives in radiotherapies of paraganglioma patients are outlined since they hold promising approaches in the near future that can improve patient outcomes.

Treatment for paraganglioma with stereotactic radiotherapy

BACKGROUND

Paragangliomas (PG) are rare neoplasms of neuroendocrine origin that tend to be highly vascularized, slow-growing, and usually sporadic. To date, common treatment options are surgical resection (SR), with or without radiation therapy (RT), and a watch-and-wait approach.

AIM

To evaluate the local control and effectiveness of exclusive fractionated stereotactic RT (FSRT) treatment in unresectable PG (uPG).

METHODS

We retrospectively evaluated patients with uPG (medically inoperable or refused SR) treated with FSRT with a Cyberknife System (Accuray Incorporated, Sunnyvale, California). Toxicity and initial efficacy were evaluated.

RESULTS

From May 2009 to January 2023, 6 patients with a median age of 68 (range 20-84) were treated with FSRT. The median delivered dose was 21 Gy (range 20-30 Gy) at a median isodose line of 75.5% (range 70%-76%) in 4 fractions (range 3-5 fractions). The median volume was 13.6 mL (range 12.4-65.24 mL). The median cumulative biological effective dose and equivalent dose in 2-Gy fractions were 70 Gy and 37.10 Gy respectively. Site of origin involved were the timpa-nojugular glomus (4/6), temporal bone, and cervical spine. In 1 of the 6 patients, the follow-up was insufficient; 5 of 6 patients showed a 5-year overall survival and 5-year progression-free survival of 100%. We observed negligible toxicities during and after RT. The majority of patients showed stable symptoms during follow-up. Only 1 patient developed spine metastases.

CONCLUSION

Our preliminary results on this small cohort of patients suggest that FSRT could be an effective and safe alternative to SR.

Treatment for paraganglioma with stereotactic radiotherapy

BACKGROUND

Paragangliomas (PG) are rare neoplasms of neuroendocrine origin that tend to be highly vascularized, slow-growing, and usually sporadic. To date, common treatment options are surgical resection (SR), with or without radiation therapy (RT), and a watch-and-wait approach.

AIM

To evaluate the local control and effectiveness of exclusive fractionated stereotactic RT (FSRT) treatment in unresectable PG (uPG).

METHODS

We retrospectively evaluated patients with uPG (medically inoperable or refused SR) treated with FSRT with a Cyberknife System (Accuray Incorporated, Sunnyvale, California). Toxicity and initial efficacy were evaluated.

RESULTS

From May 2009 to January 2023, 6 patients with a median age of 68 (range 20-84) were treated with FSRT. The median delivered dose was 21 Gy (range 20-30 Gy) at a median isodose line of 75.5% (range 70%-76%) in 4 fractions (range 3-5 fractions). The median volume was 13.6 mL (range 12.4-65.24 mL). The median cumulative biological effective dose and equivalent dose in 2-Gy fractions were 70 Gy and 37.10 Gy respectively. Site of origin involved were the timpa-nojugular glomus (4/6), temporal bone, and cervical spine. In 1 of the 6 patients, the follow-up was insufficient; 5 of 6 patients showed a 5-year overall survival and 5-year progression-free survival of 100%. We observed negligible toxicities during and after RT. The majority of patients showed stable symptoms during follow-up. Only 1 patient developed spine metastases.

CONCLUSION

Our preliminary results on this small cohort of patients suggest that FSRT could be an effective and safe alternative to SR.

Trends and Impact of Treatment Modalities (Surgery and Radiation Therapy) on Health Care Utilization in Patients With Glomus Jugulare Tumors (GJTs): An Inverse Probability of Treatment Weight Analysis

OBJECTIVES

The trend of practice pattern and impact on health care utilization for surgery and radiation therapy (RT) in patients with glomus jugulare tumors (GJTs) is not well defined.

METHODS

The IBM (Armonk, NY) MarketScan database was queried using the ICD-9/10 and CPT 4th edition, 2000-2020. We included patients ≥18 years of age who underwent either surgery or RT with at-least 1-year follow-up. We compared the health care utilization at 3-month, 6-month, and 1-year follow up using the inverse probability of treatment weight technique.

RESULTS

A cohort of 333 patients was identified. Of these, 72.7% (n = 242) underwent RT and 27.3% (n = 91) underwent surgery. RT use increased from 2002-2004 (50%) to 2017-2019 (91%). Patients in the surgery cohort were younger (median age 49 vs. 56 years, P < 0.0001) and had a higher 3+ comorbidity index (34% vs. 30%, P = 0.43) compared with patients in the RT cohort. Patients who underwent surgery had higher complications at index hospitalization (22% vs. 6%, P < 0.0001) and at 30 days (14% vs. 5%, P = 0.0042). No difference in combined index and 6- or 12-month payments were noted (6-months: surgery, $66m108, RT: $43m509, P = 0.1034; 12-months: surgery, $73,259, RT: $51,576, P = 0.1817). Only 4% of patients who had initial RT underwent RT and none underwent surgery at 12 months, whereas 6% of patients who had initial surgery underwent RT and 2% underwent surgery at 12 months.

CONCLUSIONS

RT plays an increasingly important role in the treatment for patients with GJTs, with fewer complications and a comparable health care utilization at 1 year.

Clinical consensus guideline on the management of phaeochromocytoma and paraganglioma in patients harbouring germline SDHD pathogenic variants

Patients with germline SDHD pathogenic variants (encoding succinate dehydrogenase subunit D; ie, paraganglioma 1 syndrome) are predominantly affected by head and neck paragangliomas, which, in almost 20% of patients, might coexist with paragangliomas arising from other locations (eg, adrenal medulla, para-aortic, cardiac or thoracic, and pelvic). Given the higher risk of tumour multifocality and bilaterality for phaeochromocytomas and paragangliomas (PPGLs) because of SDHD pathogenic variants than for their sporadic and other genotypic counterparts, the management of patients with SDHD PPGLs is clinically complex in terms of imaging, treatment, and management options. Furthermore, locally aggressive disease can be discovered at a young age or late in the disease course, which presents challenges in balancing surgical intervention with various medical and radiotherapeutic approaches. The axiom-first, do no harm-should always be considered and an initial period of observation (ie, watchful waiting) is often appropriate to characterise tumour behaviour in patients with these pathogenic variants. These patients should be referred to specialised high-volume medical centres. This consensus guideline aims to help physicians with the clinical decision-making process when caring for patients with SDHD PPGLs.

Comparison of surgical outcomes between early and advanced class of jugular paragangliomas following application of our modified surgical techniques

To compare the safety and effectiveness of surgical treatment of jugular paragangliomas (JPs) following the application of our modified surgical techniques. Fifty-six patients with JPs were analyzed for tumor classification, surgical outcomes, and intratumor blood vessels. The gross total resection in C1-2 (100%) was significantly greater than that in C3 and D (66.7%). Good postoperative facial nerve (FN) function (House-Brackmann I-II) was achieved in 89.5% C1-2 cases, which was not significantly different from C3 and D (93.3%) (P = 0.694). Preoperative and postoperative lower cranial nerve (LCN) deficits correlated with the Fisch's classification of tumors (P < 0.05), and intraoperative blood loss was greater in advanced tumors (P = 0.050). Further study showed that the cross-sectional area of intratumor blood vessels was positively associated with intraoperative blood loss (P < 0.001). Surgical excision of JPs is a safe and effective strategy, and early surgical treatment is a good option for patients with C1-2 tumors without surgical contraindications.

Feasibility Study of Stereotactic Radiosurgery Treatment of Glomus Jugulare Tumors via HyperArc VMAT

This study aims to report on the clinical validation and feasibility of utilizing a novel fully automated treatment planning and delivery system, HyperArc VMAT stereotactic radiosurgery (SRS) for glomus jugulare tumors (GJT). Independent dose verification of the HyperArc module via the MD Anderson's SRS head phantom irradiation and credentialing results showed compliance with the SRS treatment requirements per IROC MD Anderson's standard. Following the Alliance clinical trial, AAPM, RTOG protocols, and QUENTAC requirements, utilizing selected three-partial arc geometry of HyperArc module on TrueBeam Linac with 6MV-FFF beam, GJT SRS plans were generated for nine previously treated Gamma Knife (GK) radiosurgery patients using advanced Acuros-based algorithm to account for tissue inhomogeneity corrections and frameless immobilization with Q-fix mask and Encompass device insert. HyperArc VMAT produced highly conformal SRS dose distributions to GJT, a steep dose gradient around the GJT, and spared adjacent critical organs including the spinal cord (< 3.0 Gy). Due to faster patient setup and less MLC modulation through the target (average beam-on time, 6.2 minutes), the HyperArc VMAT plan can deliver a single high-dose of 18 Gy to the GJT in less than 15 minutes overall treatment time, significantly improving patient comfort and clinic workflow. Pretreatment portal dosimetry quality assurance results and independent dose verification via Monte Carlo-based physics second check met our clinical SRS protocol's requirements for treatment. Due to the highly conformal dose distribution, rapid dose fall-off, excellent sparing of adjacent critical organs, and highly precise and accurate treatment, clinical implementation of frameless HyperArc VMAT for GJT patients who may not have access to nor tolerate frame-based GK SRS treatment are underway.