Pineal parenchymal tumors: a correlation of histological features with prognosis in 66 cases

Spinal Dissemination of Pineal Parenchymal Tumors of Intermediate Differentiation Over 10 Years After Initial Treatment: A Case Report

Pineal parenchymal tumors (PPTs) are rare, accounting for less than 0.3% of all primary central nervous system (CNS) tumors. Pineal parenchymal tumors of intermediate differentiation (PPTID) (WHO grade 2 or 3) show an intermediate prognosis between pineocytoma and pineoblastoma. The clinical course is unknown, and the optimal treatment for PPTID, especially for recurrence, has not been determined. We report a case of PPTID with spinal dissemination over 10 years after treatment and survival for four years. A 56-year-old woman presented with headaches and diplopia. Computerized tomography (CT) and magnetic resonance imaging (MRI) revealed a pineal mass, but leptomeningeal dissemination was not identified on whole-spine MRI. Microsurgical gross total tumor resection (GTR) was performed, and the pathological diagnosis was PPTID (grade 3). In addition, a later study found it to harbor a KBTBD4 mutation. She underwent whole-brain radiation therapy with a focal boost. The patient was unable to continue chemotherapy for severe myelosuppression after the first course of treatment. Eleven years after the surgery, she was unable to walk, and a whole-spine MRI revealed multiple masses at C3-4, T4, and cauda equina. Fluorodeoxyglucose-positron emission tomography (FDG-PET) revealed accumulations of the same lesions. No recurrence was observed in the brain. A biopsy of the caudal portion was performed, and the histopathological findings were the same as those of the initial surgery. Spinal dissemination was refractory to chemotherapy but responded to whole spine radiotherapy with focal boost, and she remained tumor-free for four years. We considered good local control with a combination of GTR and subsequent radiation therapy to contribute to long-term survival. The timing of spinal radiation administration is controversial because of the tendency for late cerebrospinal dissemination. The importance of long-term follow-up of the spine and head is emphasized. In PPTID cases with good local control, withholding spinal radiation until spinal dissemination occurs may become a long-term treatment plan.

Understanding and Managing Pineal Parenchymal Tumors of Intermediate Differentiation: An In-Depth Exploration from Pathology to Adjuvant Therapies

BACKGROUND

Pineal parenchymal cell tumors constitute a rare group of primary central nervous system neoplasms (less than 1%). Their classification, especially the intermediate subtype (PPTIDs), remains challenging.

METHODS

A literature review was conducted, navigating through anatomo-pathological, radiotherapy, and neurosurgical dimensions, aiming for a holistic understanding of these tumors.

RESULTS

PPTIDs, occupying an intermediate spectrum of malignancy, reveal diverse histological patterns, mitotic activity, and distinct methylation profiles. Surgical treatment is the gold standard, but when limited to partial removal, radiotherapy becomes crucial. While surgical approaches are standardized, due to the low prevalence of the pathology and absence of randomized prospective studies, there are no shared guidelines about radiation treatment modalities.

CONCLUSION

Surgical removal remains pivotal, demanding a personalized approach based on the tumor extension. This review underscores the considerable variability in treatment approaches and reported survival rates within the existing literature, emphasizing the need for ongoing research to better define optimal therapeutic strategies and prognostic factors for PPTIDs, aiming for further and more detailed stratification among them.

Pineal anlage tumor: clinical and diagnostic features, and rationales for treatment

PURPOSE

To provide a treatment-focused review and develop basic treatment guidelines for patients diagnosed with pineal anlage tumor (PAT).

METHODS

Prospectively collected data of three patients with pineal anlage tumor from Germany was combined with clinical details and treatment information from 17 published cases.

RESULTS

Overall, 20 cases of PAT were identified (3 not previously reported German cases, 17 cases from published reports). Age at diagnosis ranged from 0.3 to 35.0 (median: 3.2 ± 7.8) years. All but three cases were diagnosed before the age of three years. For three cases, metastatic disease at initial staging was described. All patients underwent tumor surgery (gross-total resection: 9, subtotal resection/biopsy: 9, extent of resection unknown: 2). 15/20 patients were alive at last follow-up. Median follow-up for 10/15 surviving patients with available follow-up and treatment data was 2.4 years (0.3-6.5). Relapse was reported for 3 patients within 0.8 years after diagnosis. Five patients died, 3 after relapse and 2 from early postoperative complications. Two-year-progression-free- and -overall survival were 65.2 ± 12.7% and 49.2 ± 18.2%, respectively. All 4 patients who received intensive chemotherapy including high-dose chemotherapy combined with radiotherapy (2 focal, 2 craniospinal [CSI]) had no recurrence. Focal radiotherapy- and CSI-free survival rates in 13 evaluable patients were 46.2% (6/13) and 61.5% (8/13), respectively.

CONCLUSION

PAT is an aggressive disease mostly affecting young children. Therefore, adjuvant therapy using intensive chemotherapy and considering radiotherapy appears to comprise an appropriate treatment strategy. Reporting further cases is crucial to evaluate distinct treatment strategies.

[Pediatric brain tumors]

Pediatric central nervous system (CNS) tumors differ in their relative frequency, location, histology, biological behavior and prognosis from tumors in adults. Accurate neuropathological classification of CNS tumors is essential for therapeutic decisions and inclusion in therapy optimization studies. Tissue samples are analyzed by standardized conventional histological, immunohistological and molecular pathological methods and diagnosed according to the current World Health Organization (WHO) classification for CNS tumors (2021). By identifying characteristic genetic alterations and specific epigenetic signatures, the precision in the classification of pediatric brain tumors has significantly improved in recent years. The WHO classification allows a worldwide uniform, standardized classification of brain tumors and forms the basis for comparability of international epidemiological and clinical data. In some tumor types, such as childhood gliomas and embryonal tumors, key molecules and signaling pathways have been identified in recent years that represent starting points for new mechanism-based therapeutic modalities in the treatment of these patients.

A Pineal Parenchymal Tumor of Intermediate Differentiation in an Octogenarian Contains a Rare KBTBD4 Insertion

Pineal parenchymal tumors are rare central nervous system tumors that pose diagnostic challenges for surgical pathologists. Due to their paucity, their clinicopathologic features are still being defined. We report an 86-year-old woman with a remote history of breast lobular carcinoma who presented with a 2-month neurologic history that included gait instability, blurry vision, and headaches. Magnetic resonance imaging revealed a lobular, heterogeneously enhancing pineal region mass compressing the aqueduct of Sylvius. A biopsy performed concomitant with endoscopic third ventriculostomy consisted of small sheets of cells with eosinophilic to clear cytoplasm, multipolar processes, and ovoid nuclei with stippled chromatin. Whole exome sequencing revealed a small in-frame insertion (duplication) in exon 4 of KBTBD4 (c.931_939dup, p.P311_R313dup/ p.R313_M314insPRR), which has very recently been reported in 2 pineal parenchymal tumors of intermediate differentiation (PPTID). Additionally, variants of uncertain significance in CEBPA (c.863G > C, p.R288P) and MYC (c.655T > C, p.S219P) were identified. Although PPTID is considered a disease of young adulthood, review of 2 institutional cohorts of patients with pineal region tumors revealed that 25% of individuals with PPTID were over 65 years of age. In conclusion, PPTID should be considered in the differential diagnosis of pineal region tumors in older adults.

Pineal/germ cell tumors and pineal parenchymal tumors

INTRODUCTION

Pineal region tumors (PRTs) are tumors arising from the pineal gland and the paraspinal structures. These tumors are rare and heterogeneous that account for 2.8-10.1% and 0.6-3.2% of tumors in children and in all ages, respectively. Almost all types and subtypes of CNS tumors may be diagnosed in this region. These tumors come from cells of the pineal gland (pinealocytes and neuroglial cells), ectopic primordial germ cells (PGC), and cells from adjacent structures. Hence, PRTs are consisted of pineal parenchyma tumors (PPTs), germ cell tumors (GCTs), neuroepithelial tumors (NETs), other miscellaneous types of tumors, cystic tumors (epidermoid, dermoid), and pineal cyst in addition. The symptoms of PRTs correlate to the increased intracranial cranial pressure due to obstructive hydrocephalus and dorsal midbrain compression. The diagnostic imaging studies are mainly MRI of brain (with and without gadolinium) along with a sagittal view of whole spine. Serum and/or CSF AFP/β-HCG helps to identify GCTs. The treatment of PRTs is consisted of the selection of surgical biopsy/resection, handling of hydrocephalus, neoadjuvant and/or adjuvant therapy according to age, tumor location, histopathological/molecular classification, grading of tumors, staging, and threshold value of markers (for GCTs) in addition.

METHODS

In this article, we review the following focus points: 1. Background of pineal region tumors. 2. Pineal GCTs and evolution of management. 3. Molecular study for GCTs and pineal parenchymal tumors. 4. Review of surgical approaches to the pineal region. 5. Contribution of endoscopy. 6. Adjuvant therapy (chemotherapy, radiotherapy, and combination). 7.

FUTURE DIRECTION

RESULTS

In all ages, the leading three types of PRTs in western countries were PPTs (22.7-34.8%), GCTs (27.3-34.4%), and NETs (17.2-28%). In children and young adults, the leading PRTs were invariably in the order of GCTs (40-80.5%), PPTs (7.6-21.6%), NETs (2.4-37.5%). Surgical biopsy/resection of PRTs is important for precision diagnosis and therapy. Safe resection with acceptable low mortality and morbidity was achieved after 1970s because of the advancement of surgical approaches, CSF shunt and valve system, microscopic and endoscopic surgery. Following histopathological diagnosis and classification of types and subtypes of PRTs, in PPTs, through molecular profiling, four molecular groups of pineoblastoma (PB) and their oncogenic driver were identified. Hence, molecular stratified precision therapy can be achieved.

CONCLUSION

Modern endoscopic and microsurgical approaches help to achieve precise histopathological diagnosis and molecular classification of different types and subtypes of pineal region tumors for risk-stratified optimal, effective, and protective therapy. In the future, molecular analysis of biospecimen (CSF and blood) along with AI radiomics on tumor imaging integrating clinical and bioinformation may help for personalized and risk-stratified management of patients with pineal region tumors.

Survival and Malignant Transformation of Pineal Parenchymal Tumors: A 30-Year Retrospective Analysis in a Single-Institution

BACKGROUND

This study aims to elucidate clinical features, therapeutic strategies, and prognosis of pineal parenchymal tumors (PPT) by analyzing a 30-year dataset of a single institution.

METHODS

We reviewed data from 43 patients diagnosed with PPT at Seoul National University Hospital between 1990 and 2020. We performed survival analyses and assessed prognostic factors.

RESULTS

The cohort included 10 patients with pineocytoma (PC), 13 with pineal parenchymal tumor of intermediate differentiation (PPTID), and 20 with pineoblastoma (PB). Most patients presented with hydrocephalus at diagnosis. Most patients underwent an endoscopic third ventriculostomy and biopsy, with some undergoing additional resection after diagnosis confirmation. Radiotherapy was administered with a high prevalence of gamma knife radiosurgery for PC and PPTID, and craniospinal irradiation for PB. Chemotherapy was essential in the treatment of grade 3 PPTID and PB. The 5-year progression-free survival rates for PC, grade 2 PPTID, grade 3 PPTID, and PB were 100%, 83.3%, 0%, and 40%, respectively, and the 5-year overall survival rates were 100%, 100%, 40%, and 55%, respectively. High-grade tumor histology was associated with lower survival rates. Significant prognostic factors varied among tumor types, with World Health Organization (WHO) grade and leptomeningeal seeding (LMS) for PPTID, and the extent of resection and LMS for PB. Three patients experienced malignant transformations.

CONCLUSION

This study underscores the prognostic significance of WHO grades in PPT. It is necessary to provide specific treatment according to tumor grade. Grade 3 PPTID showed a poor prognosis. Potential LMS and malignant transformations necessitate aggressive multimodal treatment and close-interval screening.

Histopathology and molecular pathology of pediatric pineal parenchymal tumors

Pineal parenchymal tumors in children are rare. They consist of two main types, pineoblastoma (PB) and pineal parenchymal tumor of intermediate differentiation (PPTID), which are World Health Organization (WHO) grade 4 and grade 2-3 respectively. PBs are divided into four distinct molecular groups: PB-miRNA1, PB-miRNA2, PB-RB1, and PB-MYC/FOXR2. PB-RB1 and PB-MYC/FOXR2 affect young children and are associated with a dismal prognosis. PB-miRNA1 and PB-miRNA2 groups affect older children and follow a more favorable course. They are characterized by mutually exclusive alterations in genes involved in miRNA biogenesis, including DICER1, DROSHA, and DGCR8. They may be sporadic or may represent one manifestation of DICER1 syndrome. PB-RB1 tumors show alterations in the RB1 gene and may develop in the setting of congenital retinoblastoma, a condition known as "trilateral retinoblastoma." In the pediatric population, PPTIDs typically affect adolescents. They are characterized by small in-frame insertions in the KBTBD4 gene which is involved in ubiquitination.

Pineal Parenchymal Tumors With Intermediate Differentiation to Pineoblastoma: A Transitional Neuroectodermal Tumor of the Pineal Gland

Pineal tumors are quite rare and are fairly aggressive tumors seen in young adults and children. These tumors arise from the pineal region or recess from various types of cells in the gland and structures located in close propinquity to the gland. Pineal gland tumors have a heterogeneous spectrum that includes pineal parenchymal tumors (PPTs) and papillary tumors of the pineal region (PTPR). The PPTs are further subclassified into pineocytomas (Grade 1), PPTs of intermediate differentiation (grade 2 or 3), and pineoblastomas (grade 4) based on the World Health Organization (WHO) grades and histopathological features. We discuss the case of an 11-year-old male child who presented with complaints of headache for 15 days, vomiting for seven days, and diplopia for four days. On magnetic resonance imaging (MRI), a soft tissue density lesion was noticed in the posterior third ventricle region. Based on the location and the MRI findings, the differential diagnosis considered were a pineal lesion, a choroid plexus papilloma, or a meningioma. He underwent a right occipital ventriculoperitoneal shunt followed by total excision of the tumor, and the resected specimen was sent for histopathological examination. After pathologic examination, the diagnosis of pineoblastoma (grade 4) with features of a PPT of intermediate differentiation (grades 2-3) was revealed, and the same was confirmed on immunohistochemistry.

Clinicopathologic analysis of pineal parenchymal tumors of intermediate differentiation: a multi-institutional cohort study by the Kyushu Neuro-Oncology Study Group

PURPOSE

Pineal parenchymal tumors of intermediate differentiation (PPTIDs), which were recognized in the 2007 World Health Organization (WHO) classification, are rare, accounting for less than 1% of all central nervous system tumors. This rarity and novelty complicate the diagnosis and treatments of PPTID. We therefore aimed to evaluate the clinicopathological significance of this tumor.

METHODS

At 11 institutions participating in the Kyushu Neuro-Oncology Study Group, data for patients diagnosed with PPTID were collected. Central pathology review and KBTBD4 mutation analysis were applied to attain the diagnostically accurate cohort.

RESULTS

PPTID was officially diagnosed in 28 patients: 11 (39%) with WHO grade 2 and 17 (61%) with WHO grade 3 tumors. Median age was 49 years, and the male:female ratio was 1:2.1. Surgery was attempted in all 28 patients, and gross total resection (GTR) was achieved in 46% (13/28). Adjuvant radiotherapy and chemotherapy were administered to, respectively, 82% (23/28) and 46% (13/28). The 5-year progression-free survival (PFS) and overall survival rates were 64.9% and 70.4% respectively. Female sex (p = 0.018) and GTR (p < 0.01) were found to be independent prognostic factors for PFS and female sex (p = 0.019) was that for OS. Initial and second recurrences were most often leptomeningeal (67% and 100% respectively). 80% (20/25) of patients harbored a KBTBD4 mutation.

CONCLUSIONS

Female sex and GTR were independent prognostic factors in our patients with PPTID. Leptomeningeal recurrence was observed to be particularly characteristic of this tumor. The rate of KBTBD4 mutation observed in our cohort was acceptable and this could prove the accuracy of our PPTID cohort.

Accuracy of apparent diffusion coefficient values for distinguishing between pineal germ cell tumour and pineoblastoma

AIM

To differentiate between pineal germ cell tumour and pineoblastoma using apparent diffusion coefficient (ADC) values due to their overlapping imaging findings on magnetic resonance imaging (MRI).

MATERIALS AND METHODS

This retrospective study was conducted on 33 patients with pineal germ cell tumours and eight patients with pineoblastoma who underwent pretreatment MRI. Twenty-seven patients (21 with pineal germ cell tumour and six with pineoblastoma) were included for ADC measurement. The minimum and mean ADC values of the tumours were measured, with normalized tumour to control ADC ratios generated. The MRI characteristics of the tumours were evaluated.

RESULTS

The mean and minimum ADC values, normalized mean and minimum ADC ratios of pineal germ cell tumours were significantly higher than those of pineoblastomas (all p<0.005). A cut-off value of 0.92 for the normalized mean ADC ratio was used to distinguish between pineal germ cell tumour and pineoblastoma and achieved an area under the curve of 0.95, sensitivity of 90.5%, specificity of 83.3%, and accuracy of 92.6%. An equal degree of contrast enhancement to the adjacent venous sinus was the only MRI characteristic that suggested the diagnosis of pineal germ cell tumour.

CONCLUSION

The ADC values could help differentiate between pineal germ cell tumour and pineoblastoma, specifically when conventional MRI findings are indeterminate.

Large pineal parenchymal tumor of intermediate differentiation causing compression with resultant obstructive hydrocephalus: a case report

The epithalamus region contains the tiny, functionally endocrine pineal gland, which has the shape of a pinecone. Less than 1% of adult primary intracranial malignancies are pineal parenchymal tumors, which are incredibly uncommon brain tumors. A rare variety of pineal parenchymal tumors are those with intermediate differentiation. These tumors, whose namesake refers to a malignant pineal parenchymal tumor, are intermediate between pineoblastomas and pineocytomas (a benign pineal parenchymal tumor).

Case Presentation

A female patient, age 13, who had been experiencing terrible headaches on and off for a month, went to the emergency room. Along with the headache, she experienced nausea, vomiting, dizziness, and blurred eyesight. A nonenhanced computed tomography scan was used for the initial brain neuroimaging, which showed a hypodense mass posterior to the midbrain and superior to the cerebellum. A heterogeneous bulk was visible on MRI.

Clinical Outcome

The headache, vertigo, visual disturbance, nausea, and vomiting have all improved, according to the patient. Both postoperative MRIs with and without contrast revealed the resolution of the obstructive hydrocephalus and the absence of any residual enhancing mass. The patient was followed up for 2 months without any complications or adverse events.

Conclusion

One should carefully investigate a headache as the early symptom of many illnesses and rule out any other potential causes. This would therefore enable us to create a management structure for such a very unusual malignancy.

Pineal parenchymal tumor of intermediate differentiation with late spinal dissemination 13 years after initial surgery: illustrative case

BACKGROUND

Pineal parenchymal tumors of intermediate differentiation (PPTIDs) are rare in the pineal gland. A case of PPTID that disseminated to the lumbosacral spine 13 years after the total resection of a primary intracranial tumor has been reported.

OBSERVATIONS

A 14-year-old female presented with headache and diplopia. Magnetic resonance imaging revealed a pineal tumor that induced obstructive hydrocephalus. A biopsy and endoscopic third ventriculostomy were performed. Histological diagnosis revealed a grade II PPTID. Two months later, the tumor was removed via craniotomy because the postoperative Gamma Knife surgery was ineffective. Histological diagnosis confirmed PPTID, although the grade was revised from II to III. Postoperative adjuvant therapy was not performed, because the lesion had been irradiated and gross total tumor removal was achieved. She has had no recurrence in 13 years. However, pain around the anus newly appeared. Magnetic resonance imaging of the spine revealed a solid lesion in the lumbosacral spine. The lesion was subtotally resected, and histological diagnosis revealed grade III PPTID. Postoperative radiotherapy was performed, and she had no recurrence 1 year after radiotherapy.

LESSONS

Remote dissemination of PPTID can occur several years after the initial resection. Regular follow-up imaging, including the spinal region, should be encouraged.

A temporal in vivo catalog of chromatin accessibility and expression profiles in pineoblastoma reveals a prevalent role for repressor elements

Pediatric pineoblastomas (PBs) are rare and aggressive tumors of grade IV histology. Although some oncogenic drivers are characterized, including germline mutations in RB1 and DICER1, the role of epigenetic deregulation and cis-regulatory regions in PB pathogenesis and progression is largely unknown. Here, we generated genome-wide gene expression, chromatin accessibility, and H3K27ac profiles covering key time points of PB initiation and progression from pineal tissues of a mouse model of CCND1-driven PB. We identified PB-specific enhancers and super-enhancers, and found that in some cases, the accessible genome dynamics precede transcriptomic changes, a characteristic that is underexplored in tumor progression. During progression of PB, newly acquired open chromatin regions lacking H3K27ac signal become enriched for repressive state elements and harbor motifs of repressor transcription factors like HINFP, GLI2, and YY1. Copy number variant analysis identified deletion events specific to the tumorigenic stage, affecting, among others, the histone gene cluster and Gas1, the growth arrest specific gene. Gene set enrichment analysis and gene expression signatures positioned the model used here close to human PB samples, showing the potential of our findings for exploring new avenues in PB management and therapy. Overall, this study reports the first temporal and in vivo cis-regulatory, expression, and accessibility maps in PB.

Benign and Malignant Tumors of the Pineal Region

Pineal region tumors fall into five broad categories: benign pineal region tumors, glial tumors, papillary tumors, pineal parenchymal tumors, and germ cell tumors. Genetic and transcriptional studies have identified key chromosomal alterations in germinomas (RUNDC3A, ASAH1, LPL) and in pineocytomas/pineoblastomas (DROSHA/DICER1, RB1). Pineal region tumors generally present with symptoms of hydrocephalus including nausea, vomiting, papilledema, and the classical Parinaud's triad of upgaze paralysis, convergence-retraction nystagmus, and light-near pupillary dissociation. Workup requires neuroimaging and tissue diagnosis via biopsy. In germinoma cases, diagnosis may be made based on serum or CSF studies for alpha-fetoprotein or beta-HCG making the preferred treatment radiosurgery, thereby preventing the need for unnecessary surgeries. Treatment generally involves three steps: CSF diversion in cases of hydrocephalus, biopsy through endoscopic or stereotactic methods, and open surgical resection. Multiple surgical approaches are possible for approach to the pineal region. The original approach to the pineal region was the interhemispheric transcallosal first described by Dandy. The most common approach is the supracerebellar infratentorial approach as it utilizes a natural anatomic corridor for access to the pineal region. The paramedian or lateral supracerebellar infratentorial approach is another improvement that uses a similar anatomic corridor but allows for preservation of midline bridging veins; this minimizes the chance for brainstem or cerebellar venous infarction. Determination of the optimal approach relies on tumor characteristics, namely location of deep venous structures to the tumor along with the lateral eccentricity of the tumor. The immediate post-operative period is important as hemorrhage or swelling can cause obstructive hydrocephalus and lead to rapid deterioration. Adjuvant therapy, whether chemotherapy or radiation, is based on tumor pathology. Improvements within pineal surgery will require improved technology for access to the pineal region along with targeted therapies that can effectively treat and prevent recurrence of malignant pineal region tumors.

Case report: Implantation metastasis following stereotactic biopsy of pineal parenchymal tumor of intermediate differentiation in an adult patient: An exceptionally rare complication

Implantation metastasis following stereotactic biopsy in the brain had been reported as a rare complication. A 36-years-old female patient was treated with ventriculoperitoneal (VP) shunt and stereotactic biopsy of a pineal parenchymal tumor of intermediate differentiation (PPTID) with hydrocephalus. The patient underwent five cycles of radiotherapy on the pineal area. Seven years after the procedure, the patient developed left hemiparesis with the brain MRI findings showing an enhanced mass along the biopsy tract. Craniotomy tumor removal was carried out and the pathological assessment was consistent with those of the PPTID. Radiation on metastase area and craniospinal was subsequently performed. The patient was disease-free during the 2-year follow-up assessments. The potential occurrence of implantation metastasis following the stereotactic biopsy of PPTID should be considered in the treatment plan and follow-up assessments and evaluations. Expanding the radiation area to cover the entire biopsy tract may be favorable to lower the risk of implantation metastasis.

Surgical Treatment of Pineal Region Tumors: An 18 year-Experience at a Single Institution

BACKGROUND

The pineal tumor was once considered as a restricted area for surgery. Such cases are rare, with many different opinions on surgical treatment. This study aimed to review our experience of tumor treatment in the pineal region and explore the optimal treatment strategy.

METHODS

The clinical data of 72 patients with pineal tumors from January 1997 to May 2015 (18 years) were retrospectively analyzed. Preoperative preparation, pathology type, tumor resection rate, surgical approach, and follow-up outcomes were used as the indicators to evaluate the treatment efficacy.

RESULTS

The Krause approach was used in 46 cases, the Poppen approach in 10 cases, and the transcallosal-lateral ventricle-choroid fissure approach in 16 cases. The postoperative pathological results were as follows: 24 cases of germinoma, 11 of teratoma, 15 of glioma, 6 of meningioma, 11 of Pineocytoma, 2 of cholesteatoma, 2 of cavernous hemangioma, and 1 of choriocarcinoma. Further, the study included 64 cases of total surgical resections, 8 of subtotal resections, and 2 deaths. The follow-up period was from 7 months to 10 years. Further, 51 (70.8%) patients were followed up. The multivariate regression model showed that the surgical method and the pathological type contributed significantly to predicting outcomes.

CONCLUSIONS

The type of pathology, extent of excision, and surgical approach had a significant impact on the prognosis of patients. The transcallosal-lateral ventricle-choroid fissure approach for large and medium-sized pineal tumors near the posterior part of the third ventricle had good efficacy.

Pediatric Pineoblastoma: A pooled outcome study of North American and Australian therapeutic data

Background

Pineoblastoma is a rare brain tumor usually diagnosed in children. Given its rarity, no pineoblastoma specific trials have been conducted. Studies have included pineoblastoma accruing for other embryonal tumors over the past 30 years. These included only occasional children with pineoblastoma, making clinical features difficult to interpret and determinants of outcome difficult to ascertain.

Patients and Methods

Centrally or independently reviewed series with treatment and survival data from North American and Australian cases were pooled. To investigate associations between variables, Fisher’s exact tests, Wilcoxon-Mann-Whitney tests, and Spearman correlations were used. Kaplan-Meier plots, log-rank tests, and Cox proportional hazards models were used in survival analyses.

Results

We describe a pooled cohort of 178 pineoblastoma cases from Children’s Oncology Group (n=82) and institutional series (n=96) over 30 years. Children &lt;3 years of age have significantly worse survival compared to older children, with 5-year progression free survival and overall survival estimates of 13.5±5.1% and 16.2±5.3% respectively compared with 60.8±5.6% and 67.3±5.0% for ≥3 years old (both p&lt;0.0001). Multivariable analysis showed male sex was associated with worse PFS in children &lt;3 years of age (Hazard Ratio 3.93, 95% CI 1.80-8.55; p=0.0006), suggestive of sex specific risks needing future validation. For children ≥3 years of age, disseminated disease at diagnosis was significantly associated with an inferior 5-year PFS of 39.2±9.7% (HR 2.88, 95% CI 1.52-5.45; p=0.0012) and 5-year OS of 49.8±9.1% (HR 2.87, 95% CI 1.49-5.53; p=0.0016).

Conclusion

Given the rarity of this tumor, prospective, collaborative international studies will be vital to improving the long-term survival of these patients.

Characterization of high-grade pineal region lesions: the usefulness of apparent diffusion coefficient volumetric values

BACKGROUND

High-grade pineal region tumors are rare and heterogeneous types of primary central nervous system neoplasms; radiological differential diagnosis is challenging but it is important because it has a therapeutic relevance.

PURPOSE

To discriminate among high-grade pineal region tumors by combining apparent diffusion coefficient (ADC) volumetric values and qualitative features in order to predict their histology.

MATERIAL AND METHODS

Twenty-two patients with high-grade pineal region tumors were assessed by qualitative and quantitative analysis. Margins, T2-weighted signal intensity, contrast enhancement, hemorrhage, calcifications, different volumetric ADC fractions (ADC_mean, ADC_max, ADC_min) were evaluated and were compared to the histopathologic findings (cell count and proliferation index).

RESULTS

Our qualitative imaging data showed that only margins were different among different tumors and each tumor type showed peculiar age onset. ADC_mean was found the best quantitative value to discriminate high-grade tumors of the pineal region. ADC_mean correlated with proliferation index but not with cell count. ADC_mean values were lower in tumors with higher proliferation rate and a significant difference in ADC_mean values were found between germinomas and pineoblastomas, between germinomas and papillary tumors and between papillary tumors and pineoblastomas. Moreover, the cut-off value of 0.865 × 10^-3 mm²/s for ADC_mean (ADC mean threshold value) could differentiate germinoma from pineoblastomas with the best combination of sensitivity and specificity.

CONCLUSION

The ADC_mean value measured on the whole tumor, reflecting tumor proliferative activity, may be a practical and non-invasive marker for predicting tumor histology in high-grade pineal region lesions and might be useful in preoperative assessment.

Role of proliferative marker index and KBTBD4 mutation in the pathological diagnosis of pineal parenchymal tumors

Pineal parenchymal tumors (PPTs) are clinically rare and a biopsy is often required for a definitive diagnosis. To improve the accuracy of histological assessment of PPTs, we examined the proliferative capacity of PPT cells and investigated DICER1 expression and KBTBD4 mutations. This study included 19 cases of PPTs [3 pineocytomas (PCs), 10 PPTs of intermediate differentiation (PPTID), and 6 pineoblastomas (PBs)]. Immunohistochemistry for Ki-67, PHH3, and DICER1, as well as Sanger sequencing analysis for KBTBD4 mutations, was performed using formalin-fixed paraffin-embedded tissue specimens that were resected during surgery. Tumor cell proliferation was quantified using an image analysis software. For the PHH3 and MIB-1 indices, a significant difference was observed between the PPTIDs and PBs (P < 0.05). Loss of DICER1 was not specific for PB; 0/3 PCs (0.0%), 2/9 PPTIDs (22.2%), and 2/4 PBs (50.0%). KBTBD4 mutations were detected in 1/3 PCs (33.3%), 6/9 PPTIDs (66.7%), and 0/4 PBs (0.0%). Thus, combined application of the proliferative marker index and KBTBD4 mutation analysis may be useful for the differential diagnosis of PPTs. Furthermore, detection of KBTBD4 mutations using Sanger sequencing analysis may support the diagnosis of PPTID.

Incidence, Prognostic Factors, and Survival Trend in Pineal Gland Tumors: A Population-Based Analysis

Introduction

Pineal gland tumors are exceedingly rare and account for 0.4-1.0% of brain neoplasms. Their rarity has confounded a clear understanding of the prognostic factors and standards of care for these neoplasms. In this study, we aimed to investigate the incidence, prognostic indicators, and survival trend of tumors emanating from the pineal gland.

Methods

We accessed the Surveillance, Epidemiology, End Results (SEER) Program for pineal gland tumors from 1975-2016. A multivariate Cox regression model was used to investigate the impact of clinicopathological parameters on all-cause mortality. For survival trend analysis, we employed the Kaplan Meier curve and pairwise comparisons to examine the trend.

Results

We found 1,792 and 310,003 pineal gland and brain neoplasms during 1975-2016 resulting in an incidence of 0.6%. In the multivariate Cox proportional hazards model, older age, male gender, non-germ cell tumor, and receipt of chemotherapy were significantly associated with poor survival (p < 0.001). The extent of resection and radiotherapy administration did not produce survival advantages. Our result also highlighted an increased survival of pineal gland tumors over the years.

Conclusion

Our study investigated the prognostic factors that influenced survival in patients with pineal gland tumors. Chemotherapy use adversely affected patient outcomes and should be considered carefully in specific circumstances to avoid its harmful effects. These findings provide important evidence to improve current standards of care for this rare group of tumors. The survival of pineal tumors has improved over time reflecting improvements in current practice.

Pineal parenchymal tumor of intermediate differentiation: a systematic review and contemporary management of 389 cases reported during the last two decades

Pineal parenchymal tumor of intermediate differentiation (PPTID) is a WHO grade II and III tumor arising from pineal parenchymal cells. PPTID is a rare tumor accounting for less than 1% of all primary central nervous system neoplasms. Therefore, reports describing the clinical characteristics and biological features of PPTID are lacking. Moreover, the therapeutic strategy remains controversial. The current study aimed to evaluate treatment results and problems of contemporary therapeutic modalities of PPTID based on its features compared with other pineal parenchymal tumors. A comprehensive systematic literature review of 69 articles was performed, including articles on PPTID (389 patients) and similar tumors. Patient demographics, disease presentation, imaging characteristics, biological features, and current therapeutic options and their results were reviewed. We found that histopathological findings based on current WHO classification are well associated with survival; however, identifying and treating aggressive PPTID cases with uncommon features could be problematic. A molecular and genetic approach may help improve diagnostic accuracy. Therapeutic strategy, especially for grade III and aforementioned uncommon and aggressive tumors, remains controversial. A combination therapy involving maximum tumor resection, chemotherapy, and radiotherapy could be the first line of treatment. However, although challenging, a large prospective study would be required to identify ways to improve the clinical results of PPTID treatment.

Prognosticating survival of pineal parenchymal tumors of intermediate differentiation (PPTID) by grade

BACKGROUND

Pineal parenchymal tumors of intermediate differentiation (PPTID) are a rare group of pineal parenchymal tumors classified by histology as either World Health Organization (WHO) Grades 2 or 3. The rarity of these tumors in adults has left a number of clinical management questions open. Correspondingly, the aim of this study was to aggregate a large PPTID cohort with sufficient statistical power from a large national cancer database to analyze prognostic parameters.

METHODS

All PPTID patients aged over 18 years in the U.S. National Cancer Database (NCDB) between 2005 and 2016 were retrospectively reviewed. Data were summarized and survival was modeled using Kaplan-Meier and Cox regression analyses.

RESULTS

A total of 103 adult PPTID patients were identified in the NCDB with 63 (61%) WHO Grade 2 and 40 (39%) WHO Grade 3 tumors. Overall, mean age was 53 ± 18 years with even gender distribution. A total of 75 (73%) patients underwent surgical resection for diagnosis, with gross total resection (GTR) was the most common resection outcome in 50/75 (67%). Chemotherapy was utilized in 18 (17%) patients, and radiation therapy in 37 (36%) patients. Overall, 5-year survival rate was estimated to be 54% (95% CI 42-64%), with mean survival was 84 (95% CI 69-99) months. Patients with Grade 2 tumors survived statistically longer than Grade 3 tumor counterparts (P < 0.01). Overall, older age (HR 1.09, P < 0.01) was associated with shorter survival, whereas GTR (HR 0.43, P = 0.02) was associated with longer survival. Both these parameters were significant within Grade 2 and Grade 3 subgroup analyses as well.

CONCLUSIONS

PPTID are rare tumors with expected mean survival more than 5 years, although Grade 2 tumors are expected to survive longer than Grade 3 tumors. Age and gross total resection are significant independent predictors of survival in PPTID overall, as well as within Grade 2 and Grade 3 subgroups separately. The prognostic role and benefit of adjuvant therapy is yet to be elucidated, mandating more molecular and biologic research be done to further optimize clinical management in the future.

Clinical Features of Pineal Parenchymal Tumors of Intermediate Differentiation (PPTID): A Single-Institution Series

OBJECTIVE

Pineal parenchymal tumors of intermediate differentiation (PPTID) are rare tumors of the pineal gland. Their treatment is often heterogeneous due to the lack of literature to compile standardized treatments. Although no single institution has large numbers of cases, our experience has been that the clinical course is more varied and complicated than reported.

METHODS

We reviewed the clinical data for all patients with pathology found to be consistent with PPTID at our institution between the years 2006 and 2019.

RESULTS

Nine patients were identified. At initial diagnosis, all were treated with surgery and 4 of 9 patients underwent gross total resection. Adjuvant radiation therapy to the resection bed was administered in 6 of 9 patients. Mean follow-up time was 95.3 months. Mean progression-free survival was 50.5 months, with a tendency to be longer for male sex and after gross total resection. Seven patients developed a recurrence. Five of 6 known locations of first recurrences had either distant metastases or dissemination of disease. First recurrences were treated with radiation alone in 5 patients, craniospinal radiation with multiagent chemotherapy in 1 patient, and surgery with radiation therapy in 1. At last follow-up, 2 patients had died.

CONCLUSIONS

Herein, we report clinical patterns of disease progression and treatment patterns of PPTID. Many patients progressed during the follow-up period. Disseminated disease was the most common presentation at recurrence. Ultimately, given the risk of recurrence and dissemination at recurrence, more aggressive treatment strategies should be considered. Specifically, our series suggests a benefit of adjuvant radiation at initial diagnosis for grade II patients.

Clinical and molecular heterogeneity of pineal parenchymal tumors: a consensus study

Recent genomic studies have shed light on the biology and inter-tumoral heterogeneity underlying pineal parenchymal tumors, in particular pineoblastomas (PBs) and pineal parenchymal tumors of intermediate differentiation (PPTIDs). Previous reports, however, had modest sample sizes and lacked the power to integrate molecular and clinical findings. The different proposed molecular group structures also highlighted a need to reach consensus on a robust and relevant classification system. We performed a meta-analysis on 221 patients with molecularly characterized PBs and PPTIDs. DNA methylation profiles were analyzed through complementary bioinformatic approaches and molecular subgrouping was harmonized. Demographic, clinical, and genomic features of patients and samples from these pineal tumor groups were annotated. Four clinically and biologically relevant consensus PB groups were defined: PB-miRNA1 (n = 96), PB-miRNA2 (n = 23), PB-MYC/FOXR2 (n = 34), and PB-RB1 (n = 25). A final molecularly distinct group, designated PPTID (n = 43), comprised histological PPTID and PBs. Genomic and transcriptomic profiling allowed the characterization of oncogenic drivers for individual tumor groups, specifically, alterations in the microRNA processing pathway in PB-miRNA1/2, MYC amplification and FOXR2 overexpression in PB-MYC/FOXR2, RB1 alteration in PB-RB1, and KBTBD4 insertion in PPTID. Age at diagnosis, sex predilection, and metastatic status varied significantly among tumor groups. While patients with PB-miRNA2 and PPTID had superior outcome, survival was intermediate for patients with PB-miRNA1, and dismal for those with PB-MYC/FOXR2 or PB-RB1. Reduced-dose CSI was adequate for patients with average-risk, PB-miRNA1/2 disease. We systematically interrogated the clinical and molecular heterogeneity within pineal parenchymal tumors and proposed a consensus nomenclature for disease groups, laying the groundwork for future studies as well as routine use in tumor diagnostic classification and clinical trial stratification.

Pineal Gland Tumors: A Review

Simple Summary

Pineal neoplasms are tumors with different and variable morphological, histological, and radiological characteristics and, consequently different diagnosis and management. Due to their rarity, pineal tumors may be misdiagnosed. Pineal tumors, are divided into germ cell tumors, pineal parenchymal tumors and tumors that derive from adjacent structures. In this review, we report the clinical relevance of the main pineal gland tumors, underlining the importance of studying the triggering causes of pineal region carcinogenesis, to realize appropriate diagnosis and, consequently, better clinical management.

Abstract

The pineal gland is a small, pinecone-shaped endocrine gland that participates in the biological rhythm regulation of vertebrates. The recognized major product of the pineal gland is melatonin—a multifunctional endogenous indoleamine. Accumulating evidence suggests that the pineal gland is important for preserving ideal health conditions in vertebrate. Tumors of the pineal region account for approximately 3–11% of pediatric brain neoplasms but fewer than 1% of brain neoplasms in adults. It is fundamental to expand advanced imaging techniques together with both clinical and laboratory knowledge, to help to differentiate among pineal neoplasms and thus facilitate accurate primary diagnoses and proper therapeutic interventions. In this review, we report the gross anatomy of the pineal gland and its functional significance and discuss the clinical relevance of pineal gland tumors, underlining the importance of identifying the leading causes of pineal region masses.

Role of Hypofractionated Stereotactic Radiosurgery in Recurrent Pineal Parenchymal Tumors of Intermediate Differentiation: A Case Report and Review of the Literature

A pineal parenchymal tumor of intermediate differentiation (PPID) is a rare entity, and optimal treatment is still unclear. Combined multimodality treatment should be considered in PPID due to high recurrence rates. Gross total resection is the first choice of treatment, however, it may not be feasible in every case due to location. Stereotactic radiosurgery (SRS) can be considered for the treatment of primary and recurrent disease, as it enables us to deliver a high radiation dose to the target while minimizing radiation exposure to normal tissue. In this report, we present a case treated with hypofractionated SRS for recurrent/metastatic PPID after the primary tumor was controlled with the combination of surgery and conventionally fractionated radiotherapy.

Rare Primary Central Nervous System Tumors in Adults: An Overview

Overall, tumors of primary central nervous system (CNS) are quite common in adults with an incidence rate close to 30 new cases/100,000 inhabitants per year. Significant clinical and biological advances have been accomplished in the most common adult primary CNS tumors (i.e., diffuse gliomas). However, most CNS tumor subtypes are rare with an incidence rate below the threshold defining rare disease of 6.0 new cases/100,000 inhabitants per year. Close to 150 entities of primary CNS tumors have now been identified by the novel integrated histomolecular classification published by the World Health Organization (WHO) and its updates by the c-IMPACT NOW consortium (the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy). While these entities can be better classified into smaller groups either by their histomolecular features and/or by their location, assessing their treatment by clinical trials and improving the survival of patients remain challenging. Despite these tumors are rare, research, and advances remain slower compared to diffuse gliomas for instance. In some cases (i.e., ependymoma, medulloblastoma) the understanding is high because single or few driver mutations have been defined. The European Union has launched European Reference Networks (ERNs) dedicated to support advances on the clinical side of rare diseases including rare cancers. The ERN for rare solid adult tumors is termed EURACAN. Within EURACAN, Domain 10 brings together the European patient advocacy groups (ePAGs) and physicians dedicated to improving outcomes in rare primary CNS tumors and also aims at supporting research, care and teaching in the field. In this review, we discuss the relevant biological and clinical characteristics, clinical management of patients, and research directions for the following types of rare primary CNS tumors: medulloblastoma, pineal region tumors, glioneuronal and rare glial tumors, ependymal tumors, grade III meningioma and mesenchymal tumors, primary central nervous system lymphoma, germ cell tumors, spinal cord tumors and rare pituitary tumors.

Pineal parenchymal tumor of intermediate differentiation: a single-institution experience

Background

Pineal parenchymal tumors are exceedingly rare brain tumors responsible for less than 1% of all adult primary intracranial malignancies in the United States. In this study, we describe the clinicopathologic features, management, and outcomes of patients with pineal parenchymal tumor of intermediate differentiation (PPTID).

Methods

We describe a single-center, multidisciplinary team experience in managing PPTID patients over a 15-year period (January 2000 to January 2015) at The University of Texas MD Anderson Cancer Center (MDACC). Pathology was reviewed by the pathology collaborators (A.G. and G.N.F.) and retrospective chart review was performed for treatment and clinical outcomes.

Results

We identified 17 patients (9 male) with diagnosis of PPTID. Median age at diagnosis of PPTID was 37 years (range, 15-57 years). Follow-up ranged from 0.1 to 162.8 months with 6 reported deaths. Most patients presented with headaches and diplopia. Three patients had neuroaxial dissemination at initial diagnosis, and recurrence of tumor was common (7/16) despite treatment.

Conclusions

No clear prognostic factors were identified in this series. Extension of resection showed a trend toward improved survival. PPTID with neuroaxial dissemination benefits from aggressive initial treatment including craniospinal irradiation and adjuvant chemotherapy, whereas localized disease may be treated traditionally with maximum debulking followed by adjuvant radiotherapy alone. Long-term monitoring is recommended for neurotoxicity and/or late recurrence.

Advances in Diagnostic Immunohistochemistry for Primary Tumors of the Central Nervous System

As genomic characterization becomes increasingly necessary for accurate diagnosis of tumors of the central nervous system, identification of rapidly assessible biomarkers is equally important to avoid excessive cost and delay in initiation of therapy. This article reviews novel immunohistochemical markers that may be used to determine mutation status, activation of signaling pathways, druggable targets, and cell lineage in many diverse tumor types. In particular, recently added entities to the 2016 WHO classification of central nervous system tumors will be addressed, including IDH-mutant gliomas, diffuse midline glioma, epithelioid glioblastoma, angiocentric glioma, RELA-rearranged ependymoma, embryonal tumors (medulloblastoma, atypical teratoid/rhabdoid tumor, pineoblastoma, embryonal tumor with multilayered rosettes, and other genetically defined high-grade neuroepithelial tumors), and meningiomas associated with germline alterations.

Pathologic Prognostic Factors of Pineal Parenchymal Tumor of Intermediate Differentiation

INTRODUCTION

Pineal parenchymal tumor of intermediate differentiation (PPTID) is an uncommon tumor of the pineal gland. Although this behaves as a grade II/III tumor, the exact clinical behavior is not well known. There is no well-established pathologic factor that can predict the behavior of PPTID.

AIM AND OBJECTIVE

The aim of this study was to determine the pathologic prognostic factors in PPTID.

MATERIALS AND METHODS

All PPTID cases diagnosed between 2006 and 2016 were analyzed retrospectively. Immunohistochemistry for synaptophysin, neurofilament protein (NFP), glial fibrillar acid protein, NeuN, and Ki-67 were performed in all cases. Cases were classified arbitrarily into low grade (mitosis <4/10 hpf and Ki-67 <5%) and high grade (mitosis ≥4/10 hpf and Ki-67 ≥5%). Clinical details including follow-up information were retrieved from the patients' files.

RESULTS

A total of 16 patients (6 low grade and 10 high grade) were included in this study. The age ranged from 2 to 55 years (average, 28.2) with a mild male preponderance (male:female, 1.67:1). All cases showed strong and diffuse positivity for synaptophysin. Focal NFP positivity was seen in 2 low-grade and 3 high-grade tumors. Only 2 cases showed focal NeuN positivity. Average Ki-67 index was 1.7% and 12.6% in low-grade and high-grade tumors, respectively. All patients with low-grade tumor were alive without recurrence. Among the patients with high-grade tumors, 2 had local recurrence, 1 had spinal metastasis, and 3 patients died.

CONCLUSION

Mitosis and Ki-67 proliferation index are the most important pathologic prognostic factors in PPTID. NFP expression does not carry any prognostic significance.

Modeling germline mutations in pineoblastoma uncovers lysosome disruption-based therapy

Pineoblastoma is a rare pediatric cancer induced by germline mutations in the tumor suppressors RB1 or DICER1. Presence of leptomeningeal metastases is indicative of poor prognosis. Here we report that inactivation of Rb plus p53 via a WAP-Cre transgene, commonly used to target the mammary gland during pregnancy, induces metastatic pineoblastoma resembling the human disease with 100% penetrance. A stabilizing mutation rather than deletion of p53 accelerates metastatic dissemination. Deletion of Dicer1 plus p53 via WAP-Cre also predisposes to pineoblastoma, albeit with lower penetrance. In silico analysis predicts tricyclic antidepressants such as nortriptyline as potential therapeutics for both pineoblastoma models. Nortriptyline disrupts the lysosome, leading to accumulation of non-functional autophagosome, cathepsin B release and pineoblastoma cell death. Nortriptyline further synergizes with the antineoplastic drug gemcitabine to effectively suppress pineoblastoma in our preclinical models, offering new modality for this lethal childhood malignancy.

The morphological and functional characteristics of the pineal gland

Introduction

The pineal gland is a photo-neuro-endocrine organ situated inside the brain, that secretes serotonin, melatonin and N,N-dymethyltriptamine. This narrative review will address the latest information gathered on this function of the gland as well as the unknown roles it may have. The different histological and pathological findings of the pineal gland have demonstrated a role in clinical manifestations of numerous endocrine, neurological and psychiatric pathologies.

Materials

For this narrative review we used the NCBI website database PubMed. The search terms were “Pineal Gland” AND/OR “histology, melatonin, DMT, pathology”. Total number of articles included were 86.

Results

We have reviewed physiological information of melatonin and DMT, anatomical, histological and histopathological information on the pineal gland and its role in endocrine, neurological and psychiatric pathology.

Conclusion

The role of melatonin in immunity and its potential therapeutic effects show promising potential for further research. DMT seems to have a role in psychiatric pathology and potential therapeutic effects. Proper tumoral screening and diagnostic protocol are required.

Therapeutic strategy for pineal parenchymal tumor of intermediate differentiation (PPTID): case report of PPTID with malignant transformation to pineocytoma with leptomeningeal dissemination 6 years after surgery

Pineal parenchymal tumor of intermediate differentiation (PPTID) is rare. The WHO first classified PPTID in 2000 as a pineal parenchymal tumor (PPT) with an intermediate prognosis between pineocytoma (PC) and pineoblastoma (PB). It is considered an intermediate-grade tumor and divided into WHO grade II or III.The number of available reports about PPTID is presently limited, and the appropriate management for this tumor has not yet been determined.The authors report a rare case of PC in a 63-year-old woman who presented with lower-extremity weakness and gait disturbance. A pineal mass lesion was detected on MRI. A diagnosis of PC was established after microsurgical gross-total tumor resection, and the patient received no adjuvant therapy after surgery. Two years after surgery, a partial recurrence was recognized and Gamma Knife radiosurgery was performed. Fours years later, the patient developed diffuse leptomeningeal dissemination. She was successfully treated with craniospinal irradiation. Leptomeningeal dissemination may develop 6 years after the initial diagnosis of PC. A histopathological study of the recurrent tumor revealed a malignant change from PC to PPTID.The present case shows the importance of long-term follow-up of patients with PPTs following resection and the efficacy of craniospinal irradiation in the treatment of leptomeningeal dissemination.

Pineal region glioblastomas display features of diffuse midline and non-midline gliomas

INTRODUCTION

Pineal region glioblastomas (GBM) are very rare, with approximately 46 cases described in the literature. The epidemiology, pathogenesis, and treatment of these lesions are poorly characterized.

METHODS

We identified all cases of pineal region GBM treated surgically at our institution between 1990 and 2017. Demographic and clinical follow-up data were extracted from the medical records for all cases. Pathology was reviewed and classified according to 2016 World Health Organization (WHO) criteria. Specific attention was given to the frequency of histone H3 K27M mutations in these midline gliomas.

RESULTS

Eight patients (seven men, one woman) with pineal region GBM, WHO grade IV, were identified. The most common presenting symptoms were headache (75%), vision changes (75%), and gait imbalance/ataxia (50%). Median age at diagnosis was 48.5 years (range 36-74 years). Radical subtotal resection, via a supracerebellar infratentorial approach, was achieved in 75% of patients. Review of the surgical pathology revealed seven primary GBMs (including one giant cell GBM) and one pineal region GBM that developed three years after resection of a pineal parenchymal tumor of intermediate differentiation. No cases demonstrated evidence of IDH-1 R132H mutation (N = 6) or 1p/19q co-deletion (N = 3). One case tested positive for the histone H3 K27M-mutation. Targeted exome sequencing of 467 cancer-related genes revealed nonsense mutations in ATRX and NF1. Adjuvant radiation and chemotherapy was employed in 87.5% and 75.0% of patients, respectively. Median overall survival (OS) was 15 months (range 2-24 months) from GBM diagnosis.

CONCLUSIONS

This study expands the clinical and pathologic spectrum of pineal region GBM, and provides the first report of the genetic landscape of these tumors.

Pineoblastoma-The Experience at St. Jude Children's Research Hospital

BACKGROUND

Pineoblastomas are rare, supratentorial, primitive neuroectodermal tumors.

OBJECTIVE

To document outcomes with multimodal therapy and evaluate the impact that the degree of surgical resection has on outcome.

METHODS

A departmental brain tumor database was queried to identify all patients with pathologically proven pineoblastoma who were treated from January 1997 to June 2015 at St. Jude Children's Research Hospital. For each patient, we recorded demographic, pathological, radiological, surgical, and clinical follow-up data. The effect of degree of surgical resection on survival outcomes was analyzed.

RESULTS

Forty-one patients (21 male, 20 female) treated for pineoblastoma were identified. The median age at diagnosis was 5.5 years (range 0.4-28.1) and the median follow-up was 34.5 months. Nineteen patients experienced tumor relapse with a median progression-free survival of 11.3 months, and 18 ultimately succumbed to their disease. Patients who died or experienced treatment failure were younger (median, 2.69 vs 6.5 years, P = .026) and more likely to have metastatic disease at diagnosis (12 [63.2%] vs 5 [22.7%], P = .012). When analyzing only patients 5 years of age or older with focal disease at presentation, those who had a gross total resection or near-total resection-compared with subtotal resection or biopsy-had greater overall survival (75.18 vs 48.57 months), with no patients dying as a result of their cancer.

CONCLUSION

Poor prognostic variables for children with pineoblastoma include young age, metastatic disease at presentation, and tumor relapse. For patients older than 5 years with focal disease, maximal tumor resection should be the goal.

Pineal parenchymal tumour of intermediate differentiation: a rare differential diagnosis of pineal region tumours

Pineal parenchymal tumours of intermediate differentiation are a rare type of pineal parenchymal tumours. As indicated by their name, these tumours fall between pineoblastoma (a malignant pineal parenchymal tumour) and pineocytoma (a benign pineal parenchymal tumour). In this article, we present a case of pineal parenchymal tumour of intermediate differentiation that was successfully treated by resection via the supracerebellar approach. We also discuss the differential consideration based on epidemiological, pathological and radiological findings.

Primary Cerebellar Neuroendocrine Tumors: Chimeras or Real Entities? A Case Report with a 6-Year Follow-Up

We report the case of a 38-year-old patient who was diagnosed with a cerebellar well-differentiated neuroendocrine tumor (WDNET) in 2009. At first glance, we believed that it was a metastasis from an unrecognized WDNET arising outside the cerebellum. However, despite a prolonged follow-up of 6 years, an extracranial WDNET has never been found. During this time, the tumor recurred locally twice, and the patient was treated with surgery and radiotherapy. At the moment, he enjoys good general conditions and his tumor is under control. Due to the histopathological characteristics and clinical behavior of the tumor, we believe that this is the first report to date of a primary cerebellar WDNET.

Histopathologic review of pineal parenchymal tumors identifies novel morphologic subtypes and prognostic factors for outcome

BACKGROUND

Pineal parenchymal tumors (PPTs) are rare neoplasms of the central nervous system, and data concerning clinical outcomes are limited. The purpose of this study was to define the clinical behavior of PPT according to current histopathologic criteria and identify prognostic factors to guide therapeutic decisions.

METHODS

Seventy-five patients treated for PPT at a single institution between 1992 and 2015 were retrospectively identified. Forty-five resection specimens were available and re-reviewed. Freedom from progression (FFP) and overall survival (OS) were estimated using the Kaplan-Meier method and compared using log-rank tests.

RESULTS

Median follow-up was 4.1 years. All patients initially underwent surgery; 78% of patients with PPT of intermediate differentiation (PPTID) and all patients with pineoblastoma received adjuvant therapy. Pathologic re-review refined classification in 27% of cases, with the majority of these being adult patients with pineal tumors originally classified as pineoblastomas that more accurately resembled PPTID based on the 2007 WHO classification.

CLASSIFICATION

Our histologic review also identified that PPTIDs can be classified into small-cell and large-cell morphologic subtypes, which have distinct clinical outcomes. Tumor grade, extent of resection, and neuraxis spread were prognostic for FFP. PPTID subtype, extent of resection, and neuraxis spread were prognostic for OS. Genetic analysis of a pineoblastoma case identified somatic mutations of DICER1, ARID1A, and KDM5C genes.

CONCLUSIONS

PPTIDs can be classified into 1 of 2 novel morphologic subtypes that are associated with distinct clinical outcomes. Tumor grade, neuraxis spread, and extent of resection also influence outcome for patients with PPT.

Twenty-seven cases of pineal parenchymal tumours of intermediate differentiation: mitotic count, Ki-67 labelling index and extent of resection predict prognosis

OBJECTIVE

Optimal grading and treatment of pineal parenchymal tumours of intermediate differentiation (PPTID) have not been established due to their rarity. After careful review of more than 500 pineal region tumours treated in our centre, 27 patients with PPTID were identified.

METHODS

Diagnoses were confirmed according to WHO classification and graded as suggested by Jouvet et al. The relationship between the WHO grade, histopathological characters, management and outcome was analysed.

RESULTS

The WHO grade did not demonstrate significant correlation with outcome. Mitotic count and Ki-67 labelling index (LI) were detected as prognostic factors. Stratification of patients by mitotic count and Ki-67 LI correlated significantly with overall survival and progression-free survival. All the patients underwent resection. Gross total resection (GTR) was achieved in 16/27 (59.3%) patients, subtotal resection in 6/27 (22.2%) patients and partial resection in 5/27 (18.5%) patients. Log rank test confirmed GTR correlated with significantly better survival. Adjuvant therapy had a tendency to correlate significantly with progression-free survival. Among the high-risk patients, 6/9 patients with residual tumour received radiotherapy and 50% (3/6) were free of local tumour recurrence. In the other three high-risk patients with residual tumour who did not receive adjuvant therapy, recurrence occurred early and Ki-67 LI predicted prognosis.

CONCLUSIONS

Risk evaluation combining mitotic count and Ki-67 LI predicts prognosis. Surgery is the most efficient management. GTR is related to better prognosis. If GTR is not achieved, adjuvant therapy might delay tumour progression or recurrence, especially in high-risk patients.