Radiation-Induced Schwannomas and Neurofibromas: A Systematic Review

Clinical course and predictors of outcome following surgical treatment of benign peripheral nerve sheath tumors, a single center retrospective study

INTRODUCTION

Peripheral nerve sheath tumors are the most common tumor of the peripheral nerves. In general, surgery has a favorable outcome and is the treatment of choice. However, postoperative neurologic deficits are not uncommon, and predictors of outcome are poorly defined.

OBJECTIVE

To evaluate clinical outcomes after surgical treatment of benign peripheral nerve sheath tumors and identify outcome predictors that may affect preoperative decision making and improve surgical outcomes.

METHOD

In this single center retrospective study, all patients surgically treated for a benign peripheral nerve sheath tumor between 2005 and 2020 were eligible for inclusion. Medical records and imaging data were reviewed. Studied outcomes were changes in neurological symptoms, pain, and tumor recurrence. Logistic regression was performed to identify possible outcome predictors.

RESULTS

In total, 81 patients undergoing 85 separate surgeries for benign peripheral nerve sheath tumors were included. The most common preoperative symptoms were local pain (90%) followed by a noticeable mass (78%), radiating pain (72%), sensory deficit (18%), and motor deficit (16%). A postoperative improvement of symptoms was seen in 94% of those with pain, 48% of those with sensory deficits and 78% of those with motor deficits. However, 35% and 9% developed new postoperative sensory and motor deficits, respectively. Multivariable analysis showed complete tumor removal as a predictor of reduced pain (p = 0.033), and younger age and larger tumors were risk factors for persistent or increased sensory deficits (p = 0.002 and p = 0.005, respectively). There were no significant predictors of motor deficits. Neurocutaneous syndromes were associated with increased odds of tumor recurrence on univariable analysis (p = 0.008).

CONCLUSION

Surgery of benign peripheral nerve sheath tumors is a safe procedure with a favorable outcome in most cases. Younger age and larger tumors were risk factors for persistent or increased sensory deficits, while complete tumor removal was associated with reduced pain. Patients with neurocutaneous syndromes had a higher rate of tumor recurrence. To further evaluate outcome predictors, we recommend future studies to focus on longer follow-up periods to assess the natural course of postoperative neurological deficits.

Primary Retroperitoneal Ganglioneuroma: A Retrospective Cohort Study of 32 Patients

Purpose: To investigate the clinical characteristics, diagnosis, differential diagnosis, therapy options, and outcomes of retroperitoneal ganglioneuroma.

Methods: In this retrospective study, we collected and analyzed the clinical data of 32 patients diagnosed with retroperitoneal ganglioneuroma and admitted to Peking Union Medical College Hospital from October 2012 to August 2019.

Results: Among our 32 cases with retroperitoneal ganglioneuroma, the male-to-female ratio was 1:3 and the mean age was 35. Only 25% of the cases presented with abdominal pain while more than 65% had no specific symptoms. The masses could be found through physical examination in only five patients. Most of the tumors are located near the renal area. They were usually single and displayed an embedded growth pattern with diameters <10 cm, clear borders, and soft texture. For radiological imaging, the majority of tumors demonstrated soft tissue density with mild-to-moderate enhancement on CT imaging and showed hypoecho with moderate blood flow signals in ultrasound. No significantly abnormal laboratory examinations were found in most patients. Of all the 32 patients, 2 chose surveillance after biopsy due to difficulties in operation, while others chose surgical resection. The mean follow-up time was 15.8 months among 26 patients. The tumor remained stable in the surveillance cases. Residual tumors were found in four cases receiving operations with no progress and discomfort. No recurrence was seen in all patients.

Conclusions: The retroperitoneal ganglioneuroma is a benign tumor without specific clinical manifestations or significant laboratory findings. Typically, it is shown as low density with a clear border and an embedded growth pattern in radiological imaging. The overall prognosis is good. Surgery is an effective approach with possible severe complications. Incomplete resection or surveillance can be considered for some cases where complete resection is difficult to achieve.

Surgery After Surgery for Vestibular Schwannoma: A Case Series

Objective

We retrospectively evaluated the oncological and functional effectiveness of revision surgery for recurrent or remnant vestibular schwannoma (rVS).

Methods

We included 29 consecutive patients with unilateral hearing loss (16 women; mean age: 42.2 years) that underwent surgery for rVS. Previous surgeries included gross total resections (GTRs, n=11) or subtotal resections (n=18); mean times to recurrence were 9.45 and 4.15 years, respectively. House–Brackmann (HB) grading of facial nerve (FN) weakness (grades II-IV) indicated that 22 (75.9%) patients had deep, long-lasting FN paresis (HB grades: IV-VI). The mean recurrent tumor size was 23.3 mm (range: 6 to 51). Seven patients had neurofibromatosis type 2.

Results

All patients received revision GTRs. Fourteen small- to medium-sized tumors located at the bottom of the internal acoustic canal required the translabyrinthine approach (TLA); 12 large and small tumors, predominantly in the cerebellopontine angle, required the retrosigmoid approach (RSA); and 2 required both TLA and RSA. One tumor that progressed to the petrous apex required the middle fossa approach. Fifteen patients underwent facial neurorrhaphy. Of these, 11 received hemihypoglossal–facial neurorrhaphies (HHFNs); nine with simultaneous revision surgery. In follow-up, 10 patients (34.48%) experienced persistent deep FN paresis (HB grades IV-VI). After HHFN, all patients improved from HB grade VI to III (n=10) or IV (n=1). No tumors recurred during follow-up (mean, 3.46 years).

Conclusions

Aggressive microsurgical rVS treatment combined with FN reconstruction provided durable oncological and neurological effects. Surgery was a reasonable alternative to radiosurgery, particularly in facial neurorrhaphy, where it provided a one-step treatment.

Different radioinducid tumors synchrony in an acute lymphoblastic leukemia survivor

The cranial radiation-induced tumors appearance in pediatric patients treated for hematological diseases such as leukemia/T-lymphoblastic lymphoma (T-ALL/LBL) is a known phenomenon that may include lesions of different malignant degrees and require neurosurgical treatment. We present the case of a 38-year-old man referred to our department for a sudden diplopia with 6-month progressive left hemiparesis and frequent falls. After imaging tests, different intra and extraxial lesions with different radiological behavior were observed, performing a single surgical approach for their resection. The pathological anatomy confirms four histological variants: meningioma (grade 1 and 2 [atypical]), subependymoma, and cavernoma. We discuss the teratogenic role of ionizing radiation.

Incidence of and Risk Factors for Histologically Confirmed Solid Benign Tumors Among Long-term Survivors of Childhood Cancer

Importance

Survivors of childhood cancer (CCSs) face risk of developing subsequent tumors. Solid benign tumors may be cancer precursors; benign tumors and cancers may share etiologic factors. However, comprehensive data on the risk for solid benign tumors are lacking.

Objective

To quantify the incidence of and treatment-related risk factors for histologically confirmed solid nonskin benign tumors among CCSs.

Design, Setting, and Participants

This record linkage study involves the Dutch Childhood Oncology Group-Long-Term Effects After Childhood Cancer (DCOG-LATER) cohort of 6165 individuals diagnosed with childhood cancer at younger than 18 years from January 1, 1963, through December 31, 2001, in 7 Dutch pediatric centers and who survived at least 5 years after the diagnosis. Study groups eligible for record linkage from 1990 onward included 5843 CCSs (94.8%) and 883 siblings. Benign tumors were identified from the population-based Dutch histopathology and cytopathology registry (PALGA). Follow-up was completed on May 1, 2015. Data were analyzed from January 1, 1990, through May 1, 2015.

Main Outcomes and Measures

Cumulative incidence of any subsequent benign tumor for cohort strata and multivariable Cox proportional hazards regression models (hazard ratios [HRs]) were used to evaluate potential risk factors for 8 major benign tumor subtypes.

Results

Of the 5843 eligible CCSs (55.9% male), 542 (9.3%) developed a histologically confirmed subsequent benign tumor after a median follow-up of 22.7 years (range, 5.0-52.2 years). Among women, abdominopelvic radiotherapy inferred dose-dependent increased risks for uterine leiomyoma (n = 43) for doses of less than 20 Gy (HR, 1.9; 95% CI, 0.5-7.0), 20 to less than 30 Gy (HR, 3.4; 95% CI, 1.1-10.4), and at least 30 Gy (HR, 5.4; 95% CI, 2.4-12.4) compared with no abdominopelvic radiotherapy (P = .002 for trend). High-dose radiotherapy to the trunk was not associated with breast fibroadenoma (n = 45). Of 23 osseous and/or chondromatous neoplasms, 16 occurred among leukemia survivors, including 11 after total body irradiation (HR, 37.4; 95% CI, 14.8-94.7). Nerve sheath tumors (n = 55) were associated with radiotherapy (HR at 31 years of age, 2.9; 95% CI, 1.5-5.5) and a crude indicator of neurofibromatosis type 1 or 2 status (HR, 5.6; 95% CI, 2.3-13.7). Subsequent risk for benign tumors was higher than the risks for subsequent nonskin solid malignant neoplasms and for benign tumors among siblings.

Conclusions and Relevance

This record linkage study uses a unique resource for valid and complete outcome assessment and shows that CCSs have an approximately 2-fold risk of developing subsequent benign tumors compared with siblings. Site-specific new findings, including for uterine leiomyoma, osteochondroma, and nervous system tumors, are important to enable early diagnosis; this information will be the first step for future surveillance guidelines that include some benign tumors in CCSs and will provide leads for in-depth etiologic studies.

Schwannoma Formation in Childhood Cancer Survivors Exposed to Total Body Irradiation: Case Series

Childhood cancer survivors are at risk for ongoing health risks related to their initial treatment. One potential long-term complication following radiation is the development of secondary tumors, including peripheral nerve tumors, such as schwannomas. We present three adolescent and young adult (AYA)-aged survivors of pediatric cancer (22-40 years), followed in our AYA survivorship clinic. Each was found to have a schwannoma many years following total body irradiation for a childhood primary malignancy. We highlight a late effect of low-dose total body irradiation as well as the importance of long-term monitoring in this population.

The critical role of microRNAs in stress response: Therapeutic prospect and limitation

Stress response refers to the systemic nonspecific response upon exposure to strong stimulation or chronic stress, such as severe trauma, shock, infection, burn, major surgery or improper environment, which disturb organisms and damage their physical and psychological health. However, the pathogenesis of stress induced disorder remains complicated and diverse under different stress exposure. Recently, studies have revealed a specific role of microRNAs (miRNAs) in regulating cellular function under different types of stress, suggesting a significant role in the treatment and prevention of stress-related diseases, such as stress ulcer, posttraumatic stress disorder, stress-induced cardiomyopathy and so on. This paper have reviewed the literature on microRNA related stress diseases in different databases including PubMed, Web of Science, and the MiRbase. It considers only peer-reviewed papers published in English between 2004 and 2018. This review summarizes new advances in principles and mechanisms of miRNAs regulating stress signalling pathway and the role of miRNAs in human stress diseases. This comprehensive review is to provide an integrated account of how different stresses affect miRNAs and how stress-miRNA pathways may, in turn, be linked with disease, which offers some potential strategies for stress disorder treatment. Furthermore, the limitation of current studies and challenges for clinical use are discussed.