Atypical teratoid/rhabdoid tumors in adult patients: case report and review of the literature

Atypical teratoid/rhabdoid tumor in adult: case series and an integrated survival analysis

BACKGROUND

Atypical teratoid/rhabdoid tumor (AT/RT) is well documented in children but less so in adults because of its rarity.

METHOD

We report a series of five cases, a literature review and quantitative analysis of the survival outcome of adult AT/RT patients.

RESULTS

Seventy-four patients including our five cases (male: female = 16: 58) were evaluated, whose median age was 32.5 years (18-80 years). The commonest location was the sellar region. Median overall survival (OS) was 12.5 months (0.5-204.00 months). Chemotherapy was associated with OS (HR: 0.349, 95%CI: 0.176-0.694, p = 0.003), while other factors did not influence OS. From Kaplan-Meier analysis, surgery combining postoperative chemotherapy and radiotherapy was associated with better prognosis (Log Rank: χ2 = 14.662, p = 0.001).

CONCLUSIONS

Adult AT/RT is commoner in females and tends to recur rapidly after surgical resection. Chemotherapy may provide a survival benefit. Surgery combined with postoperative chemotherapy and radiotherapy was associated with better prognosis for adult AT/RT patients, though the overall prognosis was still poor.

Atypical Teratoid/Rhabdoid Tumor of the Cerebellum in an Adult: Case Report and Literature Review

BACKGROUND

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare tumor that is most frequently encountered in the pediatric patient population. AT/RT accounts for approximately 1%-2% of all pediatric central nervous system tumors and roughly 10%-20% of tumors in patients younger than 3 years of age. While AT/RT has been encountered in the adult population, the vast majority of the cases reported occur in the supratentorial space. In the existing literature, only 3 adult cases that arise from the cerebellum have ever been reported.

CASE DESCRIPTION

A 38-year-old female presented with 6 months of worsening nausea, emesis, vertigo, diplopia, and coordination difficulty. Magnetic resonance imaging revealed a T1 avidly contrast-enhancing mass, composed of both cystic and solid areas, extending from the cerebellum into the fourth ventricle. Following a gross total resection, surgical pathology was consistent with AT/RT, with tumor cell loss of integrase interactor-1 (INI-1) observed via immunohistochemical staining.

CONCLUSIONS

This case represents just the fourth ever reported case of AT/RT arising from the cerebellum in an adult and the oldest reported age to date of a cerebellar AT/RT occurring in a female. Due to the paucity of reported adult AT/RT cases, little is known about adults with AT/RT. Further reports will function to improve the general understanding of AT/RT in the adult population.

Adult Pineal Region Atypical Teratoid Rhabdoid Tumor: A Case for Aggressive Surgical and Chemoradiation Management with Comprehensive Literature Review

BACKGROUND

Atypical teratoid rhabdoid tumor (ATRT) is a rare, highly malignant central nervous system neoplasm classified as an embryonal grade IV neoplasm by the World Health Organization. ATRT generally occurs in children younger than 3 years, with 85 pathologically confirmed cases reported in adults. It is most commonly supratentorial, with only 9 confirmed adult cases localized to the pineal region.

CASE DESCRIPTION

The case is described of a 29-year-old man with a history of chronic migraines and a previously negative computed tomography scan of the head presenting with worsening headaches and new-onset diplopia with upward gaze palsy. Computed tomography and magnetic resonance imaging showed a hemorrhagic pineal mass with extension into the right thalamus. After resection, the immunohistochemical staining and cytogenetic profile proved consistent with ATRT, making it the ninth reported case of pineal ATRT in an adult, which was treated aggressively with good outcome.

CONCLUSIONS

Adult ATRT is rare, especially in the pineal region, with only 9 cases reported. Because of the aggressiveness, ATRT must be considered in the differential diagnosis of pineal region lesions because early diagnosis and aggressive treatment are key to prolonged survival.

Atypical Teratoid Rhabdoid Tumor: Two Case Reports and an Analysis of Adult Cases with Implications for Pathophysiology and Treatment

We present the first quantitative analysis of atypical teratoid rhabdoid tumors (ATRT) in adults, including two patients from our own institutions. These are of interest as one occurred during pregnancy and one is a long-term survivor. Our review of pathological findings of 50 reported cases of adult ATRT leads us to propose a solely ectodermal origin for the tumor and that epithelial–mesenchymal transition (EMT) is a defining feature. Thus, the term ATRT may be misleading. Our review of clinical findings shows that ATRT tends to originate in mid-line structures adjacent to the CSF, leading to a high rate of leptomeningeal dissemination. Thus, we hypothesize that residual undifferentiated ectoderm in the circumventricular organs, particularly the pituitary and pineal glands, is the most common origin for these tumors. We note that if growth is not arrested soon after diagnosis, or after the first relapse/progression, death is almost universal. While typically rapidly fatal (as in our first case), long-term remission is possible (as in our second). Significant predictors of prognosis were the extent of resection and the use of chemotherapy. Glial differentiation (GFAP staining) was strongly associated with leptomeningeal metastases (chi-squared p = 0.02) and both predicted markedly worse outcomes. Clinical trials including adults are rare. ATRT is primarily a disease of infancy and radiotherapy is generally avoided in those aged less than 3 years old. Treatment options in adults differ from infants in that cranio-spinal irradiation is a viable adjunct to systemic chemotherapy in the adult population. Given the grave prognosis, this combined approach appears reasonable. As effective chemotherapy is likely to cause myelosuppression, we recommend that stem-cell rescue be available locally.

Does Stereotactic Radiosurgery Positively Impact the Local Control of Atypical Teratoid Rhabdoid Tumors?

BACKGROUND

Atypical teratoid rhabdoid tumors (ATRTs) are rare and aggressive tumors, usually affecting patients younger than 3 years of age, that are characterized by a poor prognosis. Nowadays multimodal management, including surgery, chemotherapy and radiation therapy (RT), is advocated depending on the patients' age and tumor stage, even if no consensus exists regarding the best treatment modality. Local RT seems to be the most effective treatment in prolonging progression-free and overall survival rates, although RT might not be used on younger children because of the risk of neurocognitive and endocrine sequelae. Stereotactic radiosurgery (SRS) is a valuable alternative therapeutic option to conventional RT because of the more conformal dose delivery. The aim of this study was to review the available literature on SRS in the management of ATRT.

METHODS

The authors carried out a systematic review of PubMed, Web of Science, and Google Scholar for clinical reports dealing with SRS for the management of ATRT.

RESULTS

Nine studies describing 12 patients treated with SRS for ATRT were included in the analysis. Patient's clinical features, radiosurgical treatment characteristics, and follow-up data of the pertinent literature were reviewed critically. SRS represents a feasible and effective therapeutic option in the management of ATRT. Local control has been reported in 66.7% of cases; however, 33.3% of patients experienced poor survival because of craniospinal tumor dissemination.

CONCLUSION

SRS should be considered in the multimodal treatment of ATRT, and future studies should focus on a better definition of the role played by SRS in their management.

[Molecular methods in diagnosis of poorly differentiated malignant brain tumors in children]

The histological diagnosis of malignant brain tumors in children is a complex process. In some cases, glioblastoma, primitive neuroectodermal tumor of the central nervous system, and atypical teratoid/rhabdoid tumor have a histological type similar to that of small blue round cell malignant tumor. Despite the similar histology, biological properties and approaches to treatment, these neoplasms are completely different and require their own treatment protocols. We retrospectively reviewed the most malignant types of childhood tumors and analyzed our own experience to propose a diagnostic algorithm for intracerebral small blue round cell malignant tumors in children based on the use of immunohistochemistry and fluorescence in situ hybridization.

Intracranial atypical teratoid rhabdoid tumor: current management and a single institute experience of 15 patients from north India

OBJECTIVE

We intended to assess the clinicopathological features and treatment outcome in patients of intracranial atypical teratoid rhabdoid tumor (AT/RT), a rare malignant tumor of the brain.

METHODS

Medical records were reviewed and clinical data collected on AT/RT in a 6-year period (2006-2012). Overall survival was analyzed by Kaplan-Meier method. Univariate analysis of factors predictive of overall survival was done by log-rank test.

RESULTS

Fifteen patients met the study criterion (male:female = 4:1). Median age at presentation was 5 years (range, 0.8-8 years). Presenting complaints included vomiting (73.33 %), headache (46.67 %), orbital symptoms (33.33 %), motor impairment (26.67 %), gait abnormality (20 %), and seizure (20 %). Median duration of symptoms was noted to be 2 months (range, 0.5-6 months). On contrast-enhanced MRI of brain, tumor location was supratentorial in 60 % patients and infratentorial in 40 % of patients. Cystic component and hydrocephalus were noted in 73.33 % patients each, whereas contrast enhancement and calcification were discerned in 53.33 and 40 % of the patients, respectively. All patients underwent tumor resection-gross total (26.67 %), near-total (13.33 %) and subtotal (60 %). Histopathology was confirmative of AT/RT with MIB-1 labeling index varying from 11 to 85 % (median 45 %). There was a lack of immunostaining for INI-1 protein, suggesting INI-1gene mutation or deletion. Adjuvant radiation (36 Gray/20 fractions/4 weeks to entire neuraxis followed by local boost 20 Gray/10 fractions/2 weeks) was started in six patients (40 %) and completed in five patients. Young age at presentation and poor performance status precluded the use of radiation in the remainder. Systemic chemotherapy was administered in ten (66.67 %) patients. Median number of cycles given was three (range, 1-12) with ICE (ifosfamide, carboplatin, etoposide) and VAC (vincristine, dactinomycin, cyclophosphamide) being the common regimens (26.67 and 20 %, respectively). After a median follow-up of 8.33 months (mean, 12.27 months), median overall survival was noted to be 10 months. At last follow-up, two patients are in complete response, one patient is on treatment, three patients are alive with evidence of disease, and nine patients expired due to disease progression. The 1- and 2-year actuarial rate of overall survival was noted to be 48.1 and 24.1 %, respectively. On univariate analysis, extent of surgery (p = 0.0149), use of craniospinal radiation (p = 0.0087), and MIB1 labeling index (p = 0.0034) were significant predictors of overall survival while age (≥5 years versus <5 years) was of borderline significance (p = 0.08).

CONCLUSIONS

Median survival of 10 months reflects the aggressive biology of this rare neoplasm. Maximal safe resection followed by craniospinal irradiation and systemic chemotherapy with ICE or VAC regimen is a reasonable treatment strategy in this uncommon malignancy.

[About a rare case of atypical rhabdoid teratoid tumor of the central nervous system in a pregnant woman]

Les tumeurs rhabdoïdes tératoïdes atypiques du système nerveux central sont des tumeurs pédiatriques rares et de mauvais pronostic. La littérature rapporte une dizaine de cas chez l'adulte dont deux survenus au cours d'une grossesse. Nous rapportons dans ce travail, le cas d'une femme de 25 ans, enceinte de 14 semaines d'aménorrhée, qui a été opérée pour une tumeur rhabdoïde tératoïde atypique de la fosse cérébrale postérieure. Un complément thérapeutique a été discuté chez la patiente après interruption thérapeutique de grossesse, mais la patiente fut décédée avant de démarrer le traitement adjuvant. Nous décrivons brièvement les caractéristiques des tumeurs rhabdoïdes, et les particularités de sa prise en charge chez l'adulte.

Adult-onset sellar and suprasellar atypical teratoid rhabdoid tumor treated with a multimodal approach: a case report

We report a very rare case of sellar and suprasellar atypical teratoid rhabdoid tumor (ATRT) in a 42-year-old female patient. The tumor was removed subtotally with a transsphenoidal approach. Histopathologic study showed rhabdoid cells with prominent nucleoli and abundant cytoplasm. Immunohistochemistry for INI1 was completely negative in the tumor cells, consistent with ATRT. After surgery, she received radiotherapy including spinal irradiation with proton beam therapy and subsequent chemotherapy, with no evidence of recurrence for more than 2 years. Up to date, this is the 8th case of an adult-onset ATRT in the sellar or suprasellar region. Despite its rarity, ATRTs should be considered in the differential diagnosis of an unclear malignant sellar or suprasellar lesion in adult patients and the treatment strategies for adult ATRT patients could be differentiated from those of pediatric ATRT patients.

Atypical teratoid/rhabdoid tumor in sellar turcica in an adult: A case report and review of the literature

Background:

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare central nervous system tumor composed of primitive rhabdoid cells that may differentiate along neuroectodermal, mesenchymal and epithelial lineages. AT/RT in adults is rare but not completely exceptional. It generally arises from the posterior fossa of infants, but the broad majority of the reported AT/RT in adults manifested supratentorially with the exception of four cases that arose in the cerebellum and two that arose in the spinal cord.

Case Description:

A 44-year-old female complained of visual disturbance. We performed craniotomies twice and removed partially for each time, but any malignant cells were not found in the specimens. Finally, we determined histological diagnosis from the extended lesion. She died of respiratory failure 17 months after the initial treatment.

Conclusion:

AT/RT should be considered in the differential diagnosis of a sellar lesion in adult patients. However AT/RT is rare in adults, the appropriate immunohistochemical evaluation should be performed to diagnose this rare entity.

Radiological image features of the atypical teratoid/rhabdoid tumor in adults: a systematic review

PURPOSE

Atypical teratoid/rhabdoid tumor (AT/RT) occurs in children less than 3 years old, and has a very poor prognosis. AT/RT seldom occurs in adult. We have experienced four cases of AT/RT at our institute. The purpose of this study is to evaluate the radiological image findings of adult-onset AT/RT and to conduct a systematic review.

METHODS

Image findings of four AT/RTs in our institute were retrospectively evaluated by an experienced neuroradiologist. If the images were unavailable, image findings were evaluated from the former image interpretation report. We assembled papers of adult-onset AT/RT (n = 38) and evaluated the image findings.

RESULTS

AT/RT occurs in a variety of sites (spinal region, pineal region, suprasellar region, jugular foramen, and so on). High density on computed tomography (CT) was seen in 10 of 11 cases; mixed intensity in T2-weighted image was seen in 13 of 18 cases; and high intensity on diffusion-weighted image (DWI) was seen in 3 of 3 cases. Contrast enhancement was observed in all cases in which images were available.

CONCLUSIONS

We have experienced four adult-onset AT/RT cases at our institute and have evaluated image findings through systematic review. The image findings of high density on CT, high intensity on DWI, with low apparent diffusion coefficient, and a heterogenous component should lead to an inclusion of AT/RT in the differential diagnosis of a tumor; these findings may be able to suggest AT/RT; however, they cannot make the diagnosis.

Rhabdoid glioblastoma: a recently recognized subtype of glioblastoma

BACKGROUND

Rhabdoid glioblastoma is a rare type of recently described malignant brain tumor. It is characterized by a glioblastoma associated with rhabdoid components.

METHODS

Here we report two cases of rhabdoid glioblastoma and a brief literature review. The first patient was a 19-year-old boy who initially presented with a foul-smelling odor and progressive right-side weakness. The second case was a 29-year-old male patient who presented only with a severe headache.

RESULTS

Both of these patients were young, and the disease progression was quick despite optimal treatment.

CONCLUSION

The diagnosis of rhabdoid glioblastoma was confirmed after microscopic and immunohistochemical findings.

Atypical presentation of atypical teratoid rhabdoid tumor in a child

Atypical Teratoid Rhabdoid Tumor (ATRT) is a rare malignant intracranial neoplasm more commonly diagnosed in young children. The authors report the case of an 11-year-old boy with a long standing history of slowly progressive weight loss, fatigue, and weakness over 1.5 years whose magnetic resonance imaging revealed a large heterogeneous enhancing dorsally exophytic lower brainstem mass. Examination revealed extreme cachexia, gaze-evoked nystagmus, dysphagia, dysarthria, bilateral dysmetria, and global weakness without ambulation. The protracted history and neuroimaging features were most suggestive of a low grade glioma. However, pathology revealed a hypercellular tumor with large hyperchromatic nucleoli and loss of INI-1 staining on immunohistochemistry consistent with a diagnosis of an ATRT. The child died shortly after surgery due to complications from his brainstem infiltrative disease. This case illustrates the diverse presentation of ATRT in childhood that can clinically and radiographically mimic that of low grade glioma.

Hemorrhagic onset of rhabdoid meningioma after initiating treatment for infertility

Rhabdoid meningioma (RM) is a rare aggressive phenotype and is classified as a grade III neoplasm by the World Health Organization. A 29-year-old woman initiated treatment with clomiphene citrate for infertility. Two weeks later, she presented with acute headache and nausea. Brain computed tomography and magnetic resonance imaging demonstrated a tumor with hematoma in the left frontoparietal region. Surgical resection was performed, and the tumor was subtotally removed. The tumor was diagnosed as a rhabdoid meningioma (RM). Despite radiation and chemotherapy, she experienced regrowth and dissemination to the spinal cord. She died 11 months after onset of symptoms. Spontaneous hemorrhage is an unusual presentation of RM. In our case, infertility treatment may have triggered progression and bleeding because of an imbalance of sex hormones.

Malignant brain tumor with rhabdoid features in an adult

Rhabdoid tumor (RT) of the central nervous system is an uncommon and aggressive neoplasm that usually affects pediatric patients. Currently, these tumors are classified as malignant RT or atypical teratoid/RT. Another entity of intraparenchymal brain tumor with a rhabdoid component is the extremely rare rhabdoid glioblastoma. A 23-year-old woman presented with a malignant RT in the right thalamus. The tumor was adjacent to the right lateral ventricle and was partially resected. Histological examination revealed prominent proliferation of rhabdoid cells, which is consistent with a diagnosis of malignant RT; the typical features of glioblastoma were not observed. The tumor cells stained positively for integrase interactor-1 and glial fibrillary acidic protein. Therefore, the tumor may have originated from glial components. Genetic analysis using comparative genomic hybridization showed a deoxyribonucleic acid copy-number gain on chromosome 7 but not on chromosome 22. The tumor did not respond to chemotherapy or radiotherapy, and the patient survived for only 4 months after surgery. The present case of malignant RTs shows certain similarities with those of rhabdoid glioblastoma. Further accumulation and analysis of data, including data from genetic analyses, may lead to the identification of a new type of malignant RT.

Atypical teratoid/rhabdoid tumors in adults: a case report and treatment-focused review

Atypical teratoid/rhabdoid tumor is predominantly a childhood tumor and has only been rarely reported in adults; therefore, treatment regimens are often extrapolated from the pediatric experience. Typically, children are treated with craniospinal radiation therapy which is often followed by systemic chemotherapy. Employing pediatric regimens to treat this tumor in adult patients poses a particular risk for myelosuppression, as the prescribed doses in pediatric protocols exceed those tolerated by adults, and conventional craniospinal radiation can be associated with prolonged myelotoxicity and a depletion of the bone marrow reserve in vertebrae of adults. Here we present a case of a woman with a pineal region atypical teratoid/rhabdoid tumor, an unusual adult cancer presenting in an atypical location. This is followed by a review of the disease in adult patients with an emphasis on treatment and suggestions to minimize myelotoxicity.

Atypical teratoid/rhabdoid tumors in adult patients: CT and MR imaging features

Primary AT/RT is a rare highly malignant tumor of the CNS, usually occurring in children younger than 5 years of age. The objective of this study was to characterize the CT and MR imaging findings in a series of 5 adult patients with pathologically proved AT/RT. All 5 AT/RTs were supratentorial. In 2 patients who underwent nonenhanced CT, the tumors appeared isoattenuated, and 1 of the 2 tumors contained calcifications. Solid portions of the tumors on MR imaging were isointense on T1-weighted, T2-weighted, and FLAIR images, and 1 case showed restricted diffusion on DWI. The tumors also demonstrated a bandlike rim of strong enhancement surrounding a central cystic area on contrast-enhanced T1-weighted imaging. One tumor was associated with destruction of the calvaria. Although AT/RTs can have nonspecific findings, the tumors in our series were large and isointense on T1-weighted, T2-weighted, and FLAIR images with central necrosis and prominent rim enhancement.

Atypical teratoid/rhabdoid tumor of the pineal region in an adult

An atypical teratoid/rhabdoid tumor (AT/RT) is a highly malignant embryonal tumor most often occurring in the posterior fossa in children younger than 3 years of age. Adult cases of AT/RT are very rare, and 27 cases with a diagnosis of either AT/RT or (malignant) rhabdoid tumor have been reported to date. The authors report an adult case of an AT/RT occurring in the pineal region with molecular cytogenetic and immunohistochemical confirmation. A 33-year-old woman presented with a 2-month history of headache and blurred vision progressing to diplopia, and was admitted emergently due to deteriorating mental status. An MR image showed a heterogeneously enhancing mass involving the posterior third ventricle and pineal region with mild hydrocephalus. She underwent a subtotal resection of the tumor and was then treated with chemoradiation. Thirteen months after surgery, she was still alive with radiological evidence of recurrence/residual lesions. Histological sections showed epithelioid cellular sheets of rhabdoid tumor cells with scattered mitotic figures. Immunohistochemically, the tumor cells were diffusely and strongly positive for epithelial membrane antigen and vimentin, and showed focal expression of glial fibrillary acidic protein, pancytokeratin, and neurofilament protein. Loss of nuclear immunoreactivity for INI1 protein was observed. Fluorescence in situ hybridization analysis showed monosomy 22. Histologically, this tumor consisted exclusively of epithelioid tumor cells with rhabdoid features. The differential diagnoses include rhabdoid glioblastoma, metastatic carcinoma, and rhabdoid meningioma. Molecular testing to identify monosomy 22 or deletions of the chromosome 22q11 containing the INI1/hSNF5 gene and/or immunohistochemical staining with INI1 antibody is of great importance for the diagnosis of this tumor.

[Primitive malignant rhabdoid tumor of the central nervous system in an adolescent. A case study]

Primitive malignant rhabdoid tumors of the central nervous system are rare and have a poor prognosis. Adult and adolescent cases are exceptional. We report the case of a 16-year-old girl who presented an intratumoral hemorrhage in a rhabdoid tumor. She was treated with surgery, followed by intravenous and intrathecal chemotherapy. Despite intensive treatment, she died 5 months after diagnosis. We discuss the different therapeutic options for this patient and review the literature on this kind of tumor.

Histological and immunohistochemical characterization of AT/RT: a report of 15 cases from India

Atypical teratoid rhabdoid tumor (AT/RT) is a highly malignant embryonal CNS tumor, generally unresponsive to any form of therapy, uniformly fatal within 1 year. We report 15 cases of AT/RT diagnosed at our center over a period of 5 years (2003-08). Tumors were located in different sites of the neuraxis, posterior fossa being the most common (n = 10) followed by cerebral lobes (n = 3). There was one each at the supra sellar and cervical spinal regions, respectively. Radiologically most of the tumors were heterodense and enhancing heterogeneously. The tumors exhibited diverse histological profile that included rhabdoid and PNET areas in all cases, mesenchymal and epithelial areas in 73.3% and 53.3% cases, respectively. Necrosis was evident in all cases and one showed calcification. Tumor cells displayed a polyphenotypic immunoprofile. All cases were consistently positive for vimentin and epithelial membrane antigen and were negative for desmin. Variable positivity was seen for other markers. The number of cases positive for these were: CK (53%), SMA (60%), synaptophysin (66%), NFP (33.3%) and GFAP (85%). CK staining was prominent in epithelial areas, while PNET cells labeled prominently with synaptophysin. There was lack of INI1 expression in all cases. Follow-up was available in 46.6% of cases which revealed a uniform poor prognosis.

Atypical teratoid rhabdoid tumor of the brain: case series and review of literature

INTRODUCTION

Intracranial atypical teratoid rhabdoid tumor is an uncommon malignancy with a dismal outcome. Commonly misdiagnosed over the decades as primitive neuroectodermal tumor of the brain, it has dramatically different biological behavior.

DISCUSSION

We herein report a case series of five patients diagnosed and treated as atypical teratoid rhabdoid tumor of the brain in a major cancer center in north India. We have also analyzed the clinical, histopathological, and radiological features and the therapeutic options of this enigmatic tumor.

Cerebral tumor with extensive rhabdoid features and a favorable prognosis

This 32-year-old woman, 27 weeks pregnant, harbored a cystic mass with a solid component in the left frontal lobe. Histologically, the lesion was hypercellular and contained a diffuse sheet of eosinophilic cells of various sizes. The cells were almost round and had a few prominent, eccentrically placed, hyperchromatic nuclei of various sizes. Immunohistochemically, the tumor was reactive for vimentin, epithelial membrane antigen, cytokeratin AE1/AE3, smooth muscle actin, and BAF47/INI-1, and negative for glial fibrillary acidic protein, neurofilament protein, S100 protein, CK7, CK20, HMB-45, MIC2, and Bcl-2. The Ki 67 labeling index was 4.2%. Comparative genomic hybridization analysis revealed aberrations of the chromosomal copy number of +7 and −10. This tumor could not be categorized according to the present World Health Organization classification. Results of staining with glial fibrillary acidic protein were not consistent with a glioma, and staining with INI-1 was inconsistent with atypical teratoid/rhabdoid tumor. The tumor was therefore designated as a “cerebral tumor with extensive rhabdoid features.”

Childhood atypical teratoid rhabdoid tumor of the central nervous system: a meta-analysis of observational studies

PURPOSE

Therapy for central nervous system (CNS) atypical teratoid rhabdoid tumor (ATRT) is controversial. We describe 4 children treated with sarcoma-like therapy and review the literature to evaluate outcome in relation to treatment modalities.

PROCEDURE

Reports from 1995 to 2007, describing clinical features of children (< or =18 years) were reviewed for details of demography, therapy, and outcome. Kaplan-Meier survival analyses were used to study the impact of clinical features, demography, and therapy on overall survival (OS).

RESULTS

The median OS for patients treated with multiagent chemotherapy (n=79) was 17.3 months (range, 1.5-93 mo); unrelated to age at diagnosis, sex, tumor site, and extent of resection. Overall mortality was 67%. Disease progression (craniospinal spread in 58%) was the major cause of death. Patients (n=30) treated with intrathecal (IT) chemotherapy had significantly higher 2-year OS [64% (95% confidence interval, 46.5-82.0) vs. 17.3% (95% confidence interval, 5.4-29.3); P<0.0001] and lower prevalence of distant CNS metastasis compared with those without IT therapy (n=49) (20% vs. 59.2%; P=0.001).

CONCLUSIONS

Despite dismal OS, multimodal therapy can induce remission even in metastatic CNS ATRT with partial resection. IT chemotherapy results in higher OS and, because of an overall high rate of distant relapse, should be considered in future trials.

Primary malignant rhabdoid tumour of the brain in adults

Malignant rhabdoid tumour (MRT) was described for the first time in the kidney, and is rarely reported in the brain. Most rhabdoid tumours affect infants and young children and there have been only isolated adult patients reported. The optimal treatment for this very aggressive tumour has not yet been established. We describe the clinical and pathological features of a rare primary malignant rhabdoid tumour of the brain in a 27-year-old pregnant female. The literature is reviewed briefly and the role of the INI1 gene in adult MRTs and the also possible interactions between MRTs and pregnancy are discussed.

Atypical teratoid/rhabdoid tumor of the central nervous system in an 18-year-old patient

OBJECTIVE

Atypical teratoid/rhabdoid tumors are aggressive neoplasms of the central nervous system occurring mainly in the early childhood and rarely in adults. We described a case of this tumor in an 18-year-old male patient without previous medical history.

MATERIAL AND METHODS

The neoplasm was localized in the right frontotemporal area of the brain and was totally excised. The specimen was fixed in formalin and embedded in paraffin. The histological and immunohistochemical features of the neoplasm were assessed, while sequencing analysis as well as interphase fluorescence in situ hybridization (FISH) were performed.

RESULTS

Histological and immunohistochemical analysis demonstrated atypical rhabdoid cells strongly and diffusely positive for EMA and Vimentin as well as focally immunoreactive for SMA and GFAP. Additionally, though no abnormalities detected in the coding sequence of the INI1 gene, interphase FISH studies were consistent with a homozygous deletion of the INI1 gene in the majority of examined nuclei. INI1 immunostaining demonstrated diffuse loss of nuclear INI1 expression in tumor cells. Taken together, the results were consistent with a diagnosis of atypical teratoid/rhabdoid tumor (ATRT).

CONCLUSIONS

26 previous cases of ATRT have been reported in adults, thus far. To our knowledge, this is the eighth case of an ATRT reported in an adult patient having genetic confirmation and the first one in which the tumor is, partly, localized in the right temporal area of the brain. This unusual presentation underlines the necessity of considering this devastating neoplasm in the differential diagnosis of malignant brain tumors of young adults.

Extra-renal non-cerebral rhabdoid tumours

BACKGROUND

Rhabdoid tumours (RTs) are aggressive malignancies of childhood, mainly occurring in the kidney and brain. We describe a national multi-centre retrospective analysis of extra-renal non-cranial RTs (ERRTs).

PROCEDURE

Diagnosis relied on central histological review and/or on hSNF5/INI1 defect, evidenced by immunohistochemistry or molecular screening. Clinical data were obtained from physicians.

RESULTS

Twenty six patients fulfilled the inclusion criteria. Median age at diagnosis was 28 months [0-366], including late childhood and young adults cases. Surgery, either initial or secondary, was complete in three. All but three patients received chemotherapy, with variable regimens. Additional radiotherapy was used in six patients. Median time to recurrence or progression was 5 months [0-44], and one patient remained free of disease at 7 years.

CONCLUSIONS

ERRTs share the same chemosensitivity, early recurrence, and poor prognosis as renal and cerebral RTs. No chemotherapy regimen demonstrates a superior response.

Atypical teratoid/rhabdoid tumour in sella turcica in an adult

Although atypical teratoid rhabdoid tumours preferentially arise in the posterior fossa of infants, we encountered a 56 year old woman with an atypical teratoid rhabdoid tumour located in the sella. She presented with right abducent and oculomotor nerve paresis. Magnetic resonance imaging demonstrated an intrasellar tumour impinging on the right cavernous sinus. Microscopically, the tumour was composed of cells with rhabdoid features; we observed atypia, eccentric nuclei, and intracytoplasmic inclusion bodies. The Ki-67 labeling index was around 30%. The tumour cells were positive for vimentin, epithelial membrane antigen, and neurofilament, but negative for INI1. Despite extended local brain and whole-spine irradiation she died of neural axis dissemination.

Atypical teratoid rhabdoid tumor (AT/RT) in adults: review of four cases

Atypical teratoid/rhabdoid (AT/RT) tumor is a rare, highly malignant tumor of the central nervous system (CNS) most commonly found in children less than 5 years of age. Although the vast majority of cases are diagnosed in young children, there have been isolated case reports in adults. Since its histological appearance can be confused with other tumors, especially in adults, separating AT/RT from other neoplasms may be difficult. In many instances, a reliable diagnosis is not possible without demonstrating the lack of nuclear INI1 protein expression by immunohistochemical methods. The patients (three males and one female) ranged in age from 23 to 42 years (mean age, 32 years). Radiographically, two tumors were localized in the right fronto-parietal region, one was frontal and the other was found in the left temporal lobe. Varying degrees of hydrocephalus and heterogeneous enhancement were present on MRI. In all cases, diagnosis during intraoperative consultation and preliminary diagnosis was different from the final diagnosis after immunohistochemical analysis. Immunohistochemical staining showed that the tumor cells were positive for vimentin and reacted variably for keratin, epithelial membrane antigen (EMA), synaptophysin, neurofilament protein, CD34, and smooth muscle actin (SMA). All were negative for GFAP, S-100, desmin and CD99. Three of the four cases lacked nuclear expression of INI1. One patient is alive with no evidence of disease 17 years after the diagnosis. In adult examples of AT/RT, the diagnosis requires a high index of suspicion, with early tissue diagnosis and a low threshold for investigation with INI1 immunohistochemistry to differentiate this entity from other morphologically similar tumors. Although the prognosis is dismal in pediatric population, long term survival is possible in adult AT/RT cases after surgery and adjuvant radiotherapy and chemotherapy.

Rhabdoid choroid plexus carcinoma: a rare histological type

Primary central nervous system atypical teratoid/rhabdoid tumors mostly occur during early childhood and are almost invariably fatal. These tumors show similar histological and radiological features to primitive neuroectodermal tumor, meduloblastoma and choroid plexus carcinoma, but present different biological behaviors. We present the case of an 18 year-old man who presented headache, vomiting and ataxia. CT-scan and MRI revealed a posterior fossa tumor. A gross total resection was performed. An intraoperative study showed papillary-like tumors with large cells and mitotic features. Histological examination showed two different main growth patterns: solid sheets of undifferentiated polygonal cells with papillary features and rhabdoid cells. Immunohistochemically, these rhabdoid cells were positive for vimentin, epithelial membrane antigen, smooth-muscle actin, cytokeratin, S-100 protein, and glial fibrillary acidic protein. Electro-microscopically, the typical rhabdoid cells contained whorled bundles of intermediate filaments in their cytoplasm. A rhabdoid tumor is a clinicalpathological entity and emphasizes the necessity to distinguish this unique tumor from other pediatric central nervous system neoplasms. Cytopathological features, immunohistochemistry and electro-microscopy differential diagnoses are discussed.

Atypical teratoid/rhabdoid tumor of the spine in an adult: case report and review of the literature

Atypical teratoid/rhabdoid tumors (AT/RTs) are rare, malignant brain tumors which occur almost exclusively in infants and young children. There have been only 17 cases of AT/RT in adults reported in the medical literature and the rarity of this tumor makes the diagnosis in adults difficult. We describe a case of an AT/RT of the spinal cord in an adult. A 43-year old woman presented with neck and left upper extremity pain. An MRI demonstrated a mass lesion in the dorsal spinal cord extending from C4 to C6. The patient underwent a C3 through C7 laminectomy. In consultation with senior pathologists at other institutions, the lesion was initially diagnosed as a rhabdoid meningioma. Molecular genetic studies revealed monosomy 22 and loss of expression of the INI1 gene in 22q11.2. Subsequently, immunohistochemical studies revealed the absence of INI1 gene expression in the malignant cells, supporting the diagnosis of AT/RT. The patient underwent three additional surgical procedures for recurrent disease throughout the neuraxis secondary to leptomeningeal spread of the tumor. Despite aggressive surgical resection, adjuvant chemotherapy and radiation therapy, the patient succumbed to the disease two and a half years after her initial presentation. An unrestricted autopsy was performed. To our knowledge, this is the first case of a spinal atypical teratoid/rhabdoid tumor in an adult fully documented with molecular, immunohistochemical, cytogenetic and autopsy findings.

Atypical teratoid/rhabdoid tumor: the controversy behind radiation therapy

To date, approximately 200 cases of atypical teratoid/rhabdoid tumor (AT/RT) of the central nervous system have been described in the literature. This CNS tumor tends to present at an age of less than 3 years, and most patients succumb to their disease within 1 year of diagnosis. Prior to the rise in utilization of immunohistochemical (IHC) testing in the late 1990s, this tumor was likely mistaken as medulloblastoma and treated as such. However, lessons learned from regimens based upon medulloblastoma have revealed that AT/RT requires more aggressive treatment. A significant portion of patients die of local recurrence in spite of aggressive surgery and chemotherapy. As most patients with AT/RT present as infants or young children, radiation therapy has been a less than standard treatment option. However, recent evidence suggests that long-term survival can occur with use of more aggressive treatment approaches including dose-intense chemotherapy as well as adjuvant radiation therapy. A standardized and effective approach to treating this usually fatal tumor remains elusive, and the role of radiation therapy presents a particular dilemma as young patients with this disease may experience devastating late effects of therapy if they achieve a long-term survival. Review of the literature reveals an association between initial radiation therapy and the ability to achieve a prolonged survival. Our review underscores the importance or enrolling patients in multi-institutional prospective studies to further investigate the value of radiation to treat this pediatric neoplasm.

Primary rhabdoid tumor of the brain in an adult

Rhabdoid tumor (RT) is an uncommon childhood neoplasm that typically arises within the kidney. It is characterized by an aggressive clinical course. Since its description in 1978, several cases of primary extrarenal RT, including a CNS localization, have been reported. The first case in the CNS was reported in 1985 and was defined as "rhabdoid tumor" initially, and was classified as grade IV in the most recent classification of the World Health Organization under the term of "atypical teratoid/rhabdoid tumor". Nearly 200 cases of atypical teratoid/rhabdoid tumor of the CNS have been reported to date, most of them occurring in childhood. We report a case of primary RT of the brain located in the right frontal lobe with the clinical, radiographic and pathological features presenting at an unusual age. This tumor, which was composed purely of rhabdoid cells with no additional primitive neuroectodermal, epithelial and mesenchymal components, was in a 27-year-old male patient. In conclusion, RT should be considered also in the differential diagnosis of intracerebral neoplasms of adult patients.

Atypical teratoid rhabdoid tumors of childhood: diagnosis, treatment and challenges

Atypical teratoid rhabdoid tumor of the brain was described as a unique entity in the late 1980s. It occurs primarily in early childhood but the true incidence of the disease is not yet known. At presentation, the differential diagnosis includes medulloblastoma, primitive neuroectodermal tumor, ependymoma and choroid plexus carcinoma. Atypical teratoid rhabdoid tumor behaves in a very aggressive manner and while cure is possible for a small minority of patients, no standard or effective therapy has been defined for most patients. Since its first description, considerable pathologic, cytogenetic and molecular characterizations, as described in this review, have been accomplished that provide insight into the possible molecular etiology of the disease and of malignant rhabdoid tumors that occur outside the CNS. Co-operative group clinical trials that focus solely on atypical teratoid rhabdoid tumor are needed that incorporate biologic studies along with evaluations of aggressive treatment approaches. The goal of these trials should be to increase the cure rate for children with atypical teratoid rhabdoid tumor and further increase our understanding not only of atypical teratoid rhabdoid tumor, but also of other pediatric brain tumors.

Malignant rhabdoid tumor in a pregnant adult female: literature review of central nervous system rhabdoid tumors

Rhabdoid tumors of the central nervous system are uncommon, aggressive childhood malignancies. The 13 described adult cases comprise both primary CNS tumors and malignant transformation of previously existing gliomas, meningiomas, and astrocytomas. Central nervous system rhabdoid lesions of adults have been diagnosed as primary malignant rhabdoid tumors, atypical teratoid/rhabdoid tumors, and more recently, rhabdoid glioblastomas. We report a case of a 20-year-old woman in her 30th week of pregnancy who presented with headache, nausea and blurry vision. MRI revealed a large rim-enhancing mass of the right occipital lobe. Gross total resection was achieved via a right parietal-occipital craniotomy. Pathologic evaluation revealed histology, electron microscopy and immunohistochemistry consistent with the diagnosis of malignant rhabdoid tumor. FISH studies were negative for the INI-1 genetic mutations and chromosome 22q deletion associated with childhood atypical rhabdoid/rhabdoid tumor in 75% of cases. The patient delivered her infant via caesarian section prior to initiating further therapy. We briefly describe the characteristics and current understanding of rhabdoid tumors, and review the literature comparing the 12 other cases of central nervous system rhabdoid tumors in adults. Furthermore, we consider and discuss the implications of this case being the second presentation of MRT during pregnancy in only six adult female patients.

Primary malignant rhabdoid tumor of the central nervous system--a comprehensive review

This paper presents the case of an eight-year-old girl who presented with headache and vomiting and was found to harbor a right fronto-temporo-parietal, partially cystic and centrally solid tumor that measured 11 x 8 x 7 cm. This vascular tumor was gross totally removed. The initial histopathologic diagnosis was hemangiopericytoma and the patient received a total dose of 5330 cGy of external cranial radiation. Twelve months later, the patient presented with left lower quadrant pain and limping and the spinal MR scans showed metastases at T4-5, T7, T12-L1 and L3 levels. The voluminous lesion at T12-L1 was surgically removed. Histopathological examination of both specimens revealed that both tumors in fact were malignant rhabdoid tumor (MRT). The patient did not benefit from spinal surgery and died 4 months later. A review of the literature has shown that since Briner et al'. first report in 1985 [Pediatr Pathol 3: 117-118, 1985], 100 MRT cases have been published. More than two-thirds of reviewed cases presented with local recurrence or subarachnoid spread after a mean period of 6.9 months after diagnosis and died two months later. Infratentorial and pineal location and surgery limited to biopsy were poor prognostic indicators. Twenty-two cases remained alive at a mean period of 24.5 months. The longest survival with an intracranial MRT was 65 months. Of those remaining alive, 15 had no evidence of disease (NED). Our case is the first MRT case immunopositive for HMB-45 and has also shown that the MRT cells grow aggressive over time as demonstrated by a four-fold increase in MIB-1 labeling index.

INI1 expression is retained in composite rhabdoid tumors, including rhabdoid meningiomas

Rhabdoid cells are encountered in specific entities, such as malignant rhabdoid tumor and atypical teratoid/rhabdoid tumor, as well as in composite rhabdoid tumors derived secondarily from other tumor types. Although rhabdoid tumors are uniformly aggressive, distinction of the entity from the phenotype remains important for its therapeutic implications. The majority of malignant rhabdoid tumors and atypical teratoid/rhabdoid tumors affect infants and young children, harbor chromosome 22q deletions, and inactivate the INI1/hSNF5/BAF47 tumor suppressor gene on 22q11.2. In contrast, most composite rhabdoid tumors are diagnosed in adults, with FISH detectable 22q losses the exception rather than the rule. However, this assay remains limited since 22q dosages are maintained in 20-30% of malignant rhabdoid tumors and atypical teratoid/rhabdoid tumors. Furthermore, chromosome 22 losses are common in some parent tumor types, particularly meningiomas. The recently developed INI1 antibody shows loss of nuclear expression in malignant rhabdoid tumors and atypical teratoid/rhabdoid tumors, though its status in composite rhabdoid tumors is largely unknown. Therefore, we utilized immunohistochemistry and FISH to study INI1 expression and 22q dosages, respectively, in 40 composite rhabdoid tumors, including 16 meningiomas, 15 carcinomas, three melanomas, two sarcomas, two glioblastomas, and 1 neuroblastoma. Approximately 70% of rhabdoid meningiomas had a 22q deletion, but this was rare in other tumor types. Except for one retroperitoneal leiomyosarcoma, nuclear INI1 expression was retained in all composite rhabdoid tumors, including meningiomas with 22q deletion. Therefore, we conclude that INI1 immunohistochemistry is a relatively simple, sensitive, and specific technique for distinguishing malignant rhabdoid tumor and atypical teratoid/rhabdoid tumor from composite rhabdoid tumor.