Surgery for neurofibromatosis 2

Establishment of nomograms for the prediction of useful hearing loss in patients with neurofibromatosis type 2

INTRODUCTION

Treatment for vestibular schwannoma (VS) in patients with neurofibromatosis type 2 (NF2) is extremely challenging due to the high risk of hearing loss. The aim of this study was to develop nomograms for the prediction of useful hearing loss in patients with NF2.

METHODS

The nomogram was based on a retrospective study of 111 NF2 patients who underwent resection of large VS (> 2 cm) at Beijing Tiantan Hospital between 2011 and 2018. The utility of the proposed nomogram models was evaluated by receiver operating characteristic (ROC) curve, area under ROC curve (AUC), and calibration curve. The results were validated using a prospective cohort study on 33 patients consecutively enrolled at the same institution from 2019 to 2021.

RESULTS

On multivariate analysis of the primary cohort, large tumour size (> 3 cm) and long duration of symptoms (> 24 months) were independent risk factors for preoperative useful hearing loss (AAO-HNS Class D) (P = 0.001 and P = 0.011, respectively), while large tumour size (> 3 cm), poor hearing (Class C), and lobular growth were significantly related to postoperative useful hearing loss (P < 0.001, P = 0.031 and P = 0.033, respectively). Factors derived from multivariable analysis were all assembled into the nomogram. The calibration curve for probability of hearing loss showed good agreement between predictions by nomogram models and actual observation. The ROC curves showed good predictive accuracy of the nomogram models in both cohorts (AUC: 0.708 to 0.951).

CONCLUSION

The proposed nomograms resulted in accurate predictions of hearing outcomes for patients with NF2.

Tumor Control Following Stereotactic Radiosurgery in Patients with Vestibular Schwannomas - A Retrospective Cohort Study

BACKGROUND

To better counsel vestibular schwannoma patients, it is necessary to understand the tumor control rates of stereotactic radiosurgery (SRS).

OBJECTIVES

To determine tumor control rates, factors determining control and complication rates following SRS.

METHODS

Tertiary hospital retrospective cohort.

RESULTS

579 tumors (576 patients) were treated with SRS. 477 tumors (474 patients, 82%) had ≥1 year follow up and 60% (344) ≥3 years follow up. 88% of tumors had primary SRS and 6.7% salvage SRS. Median follow up time was 4.6 years. At 3 years, the tumor control rate of primary SRS was 89% (258 of 290) in sporadic tumors compared to 43% in Neurofibromatosis type II (3 of 17) (p < 0.01). Our bivariable survival data analysis showed that Neurofibromatosis type II, documented pre-SRS growth, tumor measured by maximum dimension, SRS given as nonprimary treatment increased hazard of failure to control. There was one case of malignancy and another of rapid change following intra-tumoral hemorrhage. For tumors undergoing surgical salvage (25 of 59), 56% had a total or near-total resection, 16% had postoperative CSF leak, with 12% new facial paralysis (House-Brackmann grade VI) and worsening of facial nerve outcomes (House-Brackmann grade worse in 59% at 12 mo).

CONCLUSIONS

Control of vestibular schwannoma after primary SRS occurs in the large majority. Salvage surgical treatment was notable for higher rates of postoperative complications compared to primary surgery reported in the literature.

Vestibular Schwannoma Excision in Sporadic versus Neurofibromatosis Type 2 Populations

OBJECTIVE

To understand the differences in characteristics of neurofibromatosis type 2 (NF2) and sporadic patients with surgically excised vestibular schwannomas in the state of California.

STUDY DESIGN

Cross-sectional.

SETTING, SUBJECTS, AND METHODS

The records of all patients who underwent vestibular schwannoma excision between 1997 and 2011 were extracted from the California Hospital Inpatient Discharge Databases (CHIDD). NF2 cases were identified using ICD-9-CM diagnosis code 237.72, neurofibromatosis, type 2. All other cases were recoded as sporadic. Trends in total number and population-adjusted rates (per 1 million California residents) of surgery, demographics, hospital case volume, state of residency, complications, length of stay, total charges, expected source of payment, and disposition were examined.

RESULTS

Vestibular schwannoma (VS) excision was performed on 7017 patients, of which 464 patients (6.6%) had NF2. The population-adjusted surgery rate declined from 11.8 to 6.2 (P < .001) for sporadic cases and from 0.3 to 0.2 (P = .01) for NF2 cases over the study period. NF2 was associated with younger age (mean, 32.9 vs 51.3), higher rate of other complications (8.8% vs 4.4%) and facial nerve complications (32.3% vs 16.8%), higher total charges (median $70,106 vs $46,395), longer stay (median 5 vs 4), and high volume hospitals (80.4% vs 48.8%) (all P < .001).

CONCLUSION

The surgery rates for vestibular schwannoma excision for both sporadic and NF2 patients have declined, but the decline is more prominent for sporadic cases. NF2 patients tend to be younger and have a longer hospitalization and possibly higher corresponding hospital charges compared to patients with sporadic VS.

Familial syndromes associated with intracranial tumours: a review

BACKGROUND

Most cancers of the central nervous system (CNS) occur sporadically in the absence of any known underlying familial disorder or multi-systemic syndrome. Several syndromes are associated with CNS malignancies, however, and their recognition has significant implications for patient management and prognosis. Patients with syndrome-associated CNS malignancies often have multiple tumours (either confined to one region or distributed throughout the body), with similar or different histology.

OBJECTIVE

This review examines syndromes that are strongly associated with CNS cancers: the phakomatosis syndromes, familial syndromes such as Li-Fraumeni and familial polyposis syndromes and dyschondroplasia.