Case-based review: atypical teratoid/rhabdoid tumor

A Rare Case of Unilateral Auditory Neuropathy Induced by Proton Therapy

Hearing loss (HL) is one of the most common complications of the treatment in head and neck oncology. Most cases of HL are due to the ototoxicity of platinum-based chemotherapy (PBC) - resulting usually in a symmetric bilateral sensorineural hearing loss (SNHL) - or radiotherapy. Radiation-induced SNHL is progressive, permanent, and dose-dependent. Total dose and follow-up time are important factors affecting incidence rates. However, the hearing consequences of proton radiation therapy (PRT), a radiation-type therapy especially used in pediatric malignancies of the central nervous system (CNS), remains unclear and poorly documented. We report here a case of a four-year-old patient with unilateral auditory neuropathy spectrum disorder (ANSD) related to PRT. This case highlights the need for appropriate auditory monitoring in patients undergoing PRT for CNS or head and neck malignancies.

Sellar Atypical Teratoid/Rhabdoid Tumors (AT/RT): A Systematic Review and Case Illustration

Introduction: Atypical Teratoid/Rhabdoid tumors are rare, highly malignant tumors in adults, with a median survival of 20 months. We report a case of a sellar atypical teratoid/rhabdoid tumor in a 70-year-old female treated with intraventricular chemotherapy, followed by a systematic review of the current management of sellar AT/RTs.

Methods: A comprehensive systematic literature search was conducted on Web of Science, Scopus, and PubMed Central using the key terms “sellar” and “atypical teratoid/rhabdoid tumors”, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data, including patient demographics, histology, treatments, and overall survival were extracted and analyzed. Kaplan-Meier survival curves and log-rank analysis were used to compare survival outcomes between different treatment regimens.

Results: Our literature search disclosed 123 publications. After prespecified exclusions, 41 patients with sellar AT/RT from 30 manuscripts were identified, and 38 were included in the final analysis. Including our patient, the median age was 44 (range: 20-70) with a substantial female predominance (94.7%). Collectively, patients who received combined chemoradiation therapy had a significantly increased overall survival compared to those who received single modality or no adjuvant therapies (median OS 27 vs. 1.25 months; p=0.0052).

Conclusion: Atypical teratoid/rhabdoid tumor in the sellar region carries a poor prognosis. Adjuvant chemotherapy and radiation therapy were associated with significantly increased overall survival. Early consideration of neuro-oncology and radiation-oncology referral and management is likely beneficial in this patient population. Intrathecal chemotherapy is a treatment modality that requires further exploration given the limited options and current dismal prognosis of adult sellar AT/RT.

Clinical predictors of survival for patients with atypical teratoid/rhabdoid tumors

PURPOSE

Atypical teratoid/rhabdoid tumors (AT/RTs) are malignant central nervous system (CNS) neoplasms of the young. Our study analyzed a large AT/RT cohort from the National Cancer Database (NCDB) to elucidate predictors of short-term mortality and overall survival (OS).

METHODS

Information was collected on patients with histologically confirmed AT/RT using the NCDB (2004-2016). Kaplan-Meier analysis indicated OS. Prognostic factors for 30-day mortality, 90-day mortality, and OS were determined via multivariate Cox proportional hazards (CPH) and logistic regression models.

RESULTS

Our cohort of 189 patients had a median age of 1 year (IQR [1, 4]) and tumor size of 4.7 ± 2.0 cm at diagnosis. Seventy-two percent were under 3 years old; 55.6% were male and 71.0% were Caucasian. Fifty (27.2%) patients received only surgery (S) (OS = 5.91 months), 51 (27.7%) received surgery and chemotherapy (S + CT) (OS = 11.2 months), and 9 (4.89%) received surgery and radiotherapy (S + RT) (OS = 10.3 months). Forty-five (24.5%) received S + CT + RT combination therapy (OS = 45.4 months), 13 (17.1%) received S + CT + BMT/SCT (bone marrow or stem cell transplant) (OS = 55.5 months), and 16 (8.70%) received S + CT + RT + BMT/SCT (OS = 68.4 months). Bivariate analysis of dichotomized age (HR = 0.550, 95% CI [0.357, 0.847], p = 0.0067) demonstrated significantly increased patient survival if diagnosed at or above 1 year old. On multivariate analysis, administration of S + CT + RT, S + CT + BMT/SCT, or S + CT + RT + BMT/SCT combination therapy predicted significantly (p < 0.05) increased OS compared to surgery alone.

CONCLUSION

AT/RTs are CNS tumors where those diagnosed under 1 year old have a significantly worse prognosis. Our study demonstrates that while traditional CT, RT, and BMT/SCT combination regimens prolong life, overall survival in this population is still low.

Atypical Teratoid/Rhabdoid Tumor in Taiwan: A Nationwide, Population-Based Study

Simple Summary

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare, highly malignant CNS neoplasm with poor prognosis. A retrospective population-based analysis of patients with the diagnosis of AT/RT, registered between 1999 and 2014 in Taiwan, showed that: (1) AT/RT had a higher prevalence in males, in children < 36 months of age, and at infratentorial sites; (2) older age (≥12 months), presence of the tumor in the supratentorial region, use of radiotherapy, chemotherapy, or both were associated with better prognosis compared to surgery or no treatment. These data represent a historical experience with AT/RT in Taiwan and may inform risk stratification and clinical trial design.

Abstract

Background: Atypical teratoid/rhabdoid tumor (AT/RT) is a rare, highly aggressive embryonal brain tumor most commonly presenting in young children. Methods: We performed a nationwide, population-based study of AT/RT (ICD-O-3 code: 9508/3) in Taiwan using the Taiwan Cancer Registry Database and the National Death Certificate Database. Results: A total of 47 cases (male/female = 29:18; median age at diagnosis, 23.3 months (IQR: 12.5–87.9)) were diagnosed with AT/RT between 1999 and 2014. AT/RT had higher prevalence in males (61.70%), in children < 36 months (55.32%), and at infratentorial or spinal locations (46.81%). Survival analyses demonstrated that patients ≥ 3 years of age (n = 21 (45%)) had a 5y-OS of 41% (p < 0.0001), treatment with radiotherapy only (n = 5 (11%)) led to a 5y-OS of 60%, treatment with chemotherapy with or without radiotherapy (n = 27 (62%)) was associated with a 5y-OS of 45% (p < 0.0001), and patients with a supratentorial tumor (n = 11 (23%)) had a 5y-OS of 51.95%. Predictors of better survival on univariate Cox proportional hazard modeling and confirmed with multivariate analysis included older age (≥1 year), supratentorial sites, and the administration of radiotherapy, chemotherapy, or both. Gender had no effect on survival. Conclusion: Older age, supratentorial site, and treatment with radiotherapy, chemotherapy, or both significantly improves the survival of patients with AT/RT.

The Neurokinin-1 Receptor Is a Target in Pediatric Rhabdoid Tumors

Rhabdoid tumors (RT) are among the most aggressive tumors in early childhood. Overall survival remains poor, and treatment only effectively occurs at the cost of high toxicity and late adverse effects. It has been reported that the neurokinin-1 receptor/ substance P complex plays an important role in cancer and proved to be a promising target. However, its role in RT has not yet been described. This study aims to determine whether the neurokinin-1 receptor is expressed in RT and whether neurokinin-1 receptor (NK1R) antagonists can serve as a novel therapeutic approach in treating RTs. By in silico analysis using the cBio Cancer Genomics Portal we found that RTs highly express neurokinin-1 receptor. We confirmed these results by RT-PCR in both tumor cell lines and in human tissue samples of various affected organs. We demonstrated a growth inhibitory and apoptotic effect of aprepitant in viability assays and flow cytometry. Furthermore, this effect proved to remain when used in combination with the cytostatic cisplatin. Western blot analysis showed an upregulation of apoptotic signaling pathways in rhabdoid tumors when treated with aprepitant. Overall, our findings suggest that NK1R may be a promising target for the treatment of RT in combination with other anti-cancer therapies and can be targeted with the NK1R antagonist aprepitant.

Optical genome mapping identifies a germline retrotransposon insertion in SMARCB1 in two siblings with atypical teratoid rhabdoid tumors

In a subset of pediatric cancers, a germline cancer predisposition is highly suspected based on clinical and pathological findings, but genetic evidence is lacking, which hampers genetic counseling and predictive testing in the families involved. We describe a family with two siblings born from healthy parents who were both neonatally diagnosed with atypical teratoid rhabdoid tumor (ATRT). This rare and aggressive pediatric tumor is associated with biallelic inactivation of SMARCB1, and in 30% of the cases, a predisposing germline mutation is involved. Whereas the tumors of both siblings showed loss of expression of SMARCB1 and acquired homozygosity of the locus, whole exome and whole genome sequencing failed to identify germline or somatic SMARCB1 pathogenic mutations. We therefore hypothesized that the insertion of a pathogenic repeat‐rich structure might hamper its detection, and we performed optical genome mapping (OGM) as an alternative strategy to identify structural variation in this locus. Using this approach, an insertion of ~2.8 kb within intron 2 of SMARCB1 was detected. Long‐range PCR covering this region remained unsuccessful, but PacBio HiFi genome sequencing identified this insertion to be a SINE‐VNTR‐Alu, subfamily E (SVA‐E) retrotransposon element, which was present in a mosaic state in the mother. This SVA‐E insertion disrupts correct splicing of the gene, resulting in loss of a functional allele. This case demonstrates the power of OGM and long‐read sequencing to identify genomic variations in high‐risk cancer‐predisposing genes that are refractory to detection with standard techniques, thereby completing the clinical and molecular diagnosis of such complex cases and greatly improving counseling and surveillance of the families involved. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Infantile Brain Tumors: A Review of Literature and Future Perspectives

Brain tumors in infants including those diagnosed in fetal age, newborns and under a year old represent less than 10% of pediatric nervous system tumors and present differently when compared with older children in terms of clinical traits, location and histology. The most frequent clinical finding is a macrocephaly but non-specific symptoms can also be associated. The prognosis is usually poor and depends on several factors. Surgery continues to be the main option in terms of therapeutic strategies whereas the role of chemotherapy is not yet well defined and radiotherapy is exceptionally undertaken. In view of this situation, a molecular characterization could assist in providing therapeutic options for these tumors. This review highlights the recent advances in the diagnosis and treatment of brain tumors in infants with a particular focus on the molecular landscape and future clinical applications.

Age of diagnosis clinically differentiates atypical teratoid/rhabdoid tumors diagnosed below age of 3 years: a database study

BACKGROUND

Atypical teratoid/rhabdoid tumor (ATRT) is a rare and largely pediatric diagnosis, with poor survival. Diagnosis below the age of 3 years is characteristically seen as a poor prognostic sign. However, elucidating if clinical differences exist within this niche age group has never been attempted before. Correspondingly, we sought to characterize clinical profile of ATRT diagnoses before the age of 3 years based on separate ages of diagnosis.

METHODS

All pediatric ATRT patients aged < 3 years in the US National Cancer Database (NCDB) between 2005 and 2016 were retrospectively reviewed. Age groups were divided based on diagnoses at ages 0-1 years in group 1, 1-2 years in group 2, and 2-3 years in group 3. Data were summarized, and overall survival (OS) was modeled using Kaplan-Meier and Cox regression analyses.

RESULTS

A total of 354 ATRT diagnoses were made before the age of 3 years, with surgery used in 316 (89%) cases, chemotherapy in 242 (68%) cases, and radiation therapy in 118 (33%) cases. In terms of diagnosis age, there were 153 (43%) in group 1, 137 (39%) in group 2, and 64 (18%) in group 3. With respect to OS, median value was 9.9 months in group 1, 28.4 months in group 2, and 15.9 months in group 3. Upon multivariate analysis, receiving radiation therapy was the only parameter shared amongst all three groups as independently prognostic of longer OS (HR 0.53, P = 0.01 in group 1; HR 0.34, P < 0.01 in group 2; HR 0.31, P < 0.01 in group 3). In group 1, surgery (HR 0.47, P < 0.01) and chemotherapy (HR 0.44, P < 0.01) were also independently prognostic of longer OS. In group 3, multiple socioeconomic parameters were identified to independently predict longer OS. There were no additional predictive parameters identified in group 2.

CONCLUSION

Although ATRT diagnosed before the age of 3 is typically viewed a poor prognostic age category, our findings demonstrate that the clinical profile of this pediatric niche is highly heterogeneous based on age of diagnosis. Survival of only those diagnosed between 0 and 1 years is independently prognosticated by all three treatment modalities; patients diagnosed between 1 and 2 years trend towards longest survival, and socioeconomic parameters are most influential in those diagnosed between 2 and 3 years.

Perinatal atypical teratoid/rhabdoid tumor involving the deep ear structures and complicated by arterial infarction

Atypical teratoid/rhabdoid tumor is a malignant pediatric brain tumor. Unusual invasive behavior of the dura and bony involvement of the deep ear structures and rapid progression in size complicated by arterial infarction have not been described before. A newborn girl presented with increased intracranial pressure. Medical imaging revealed a large mass centered in the left cerebellopontine angle and left middle cranial fossa with large supra-tentorial components associated with destruction of the left petrous bone with involvement of the inner and middle ear structures. Shortly, the tumor rapidly progressed in size and complicated by left middle cerebral artery territory infarction. The patient passed away after a short hospital course. This case report illustrates how rapid and aggressive the natural history of atypical teratoid/thabdoid tumor can be with unusual skull base destruction and deep ear structures involvement.

Pineal Atypical Teratoid Rhabdoid Tumor in a 5-Month-Old Child

INTRODUCTION

Atypical teratoid rhabdoid tumors (ATRT), an uncommon malignant intracranial tumor with aggressive behavior are mostly seen in posterior fossa in young pediatric age-group.

CASE PRESENTATION

We present an infrequent location of this tumor in the pineal region in a 5-month-old infant. Also, the lesion was non-enhancing which was highly atypical of an ATRT. It was near-totally excised with the child placed in sitting position. However, within a short interval, a tumor recurrence was noted.

CONCLUSION

The case possibly represents an extended spectrum of congenital childhood brain tumors. Importantly, it highlights an atypical imaging of ATRT in very young children.