Papillary tumor of the pineal region: Histopathological characterization and review of the literature

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.

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.

Papillary tumor of the pineal region in pediatric patient – A case report

Background:

Papillary tumor of the pineal region (PTPR) represents a rare and histologically distinct subgroup of tumors originating in the pineal region. Few pediatric cases have been reported so far in the literature; therefore, clinical data are scarce.

Case Description:

We describe a case of PTPR in a 9-year-old girl who presented with a 5-month history of excessive appetite and weight gain. The patient underwent neuroimaging procedures and total gross surgical resection with postoperative adjuvant local radiotherapy, which from our experience was the best treatment choice as an attempt to avoid local recurrence. During 78-month follow-up, the patient from our study manifested no disease recurrence.

Conclusion:

PTPR should be included in the differential diagnosis of pineal region masses.

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.

Papillary tumor of the pineal region in pediatric populations: An additional case and systematic review of a rare tumor entity

Papillary tumors of the pineal region (PTPR) are a rare tumor entity first described in 2003, later codified in the 2007 WHO tumor classification system. PTPRs most commonly occur in the third and fourth decades, with exceedingly rare presentations in pediatric populations. Herein, we present an additional case of a 10-year-old female found to have PTPR in conjunction with Trisomy 21 managed successfully with cerebrospinal fluid diversion and gross total resection (GTR). Three years after resection she has returned to baseline without recurrence. We also performed a comprehensive review of the current literature discussing the diagnosis, treatment, and pathophysiologic correlations in children. Diagnosis and management of PTPRs is a topic that is increasingly garnering attention in the literature given the recent characterization of this tumor entity. However, relatively little is known about the presentation of PTPRs in pediatric populations. In adults, PTPRs have been linked with several chromosomal and genetic abnormalities; however this correlation is limited in pediatric literature. Although GTR is the mainstay for treatment, the application of adult treatment protocols may not be advisable due to age and the developmental changes of the CNS in children.

Papillary Tumor of the Pineal Region: Systematic Review and Analysis of Prognostic Factors

BACKGROUND

Clinical outcomes and biological behavior of papillary tumors of the pineal region (PTPR) are still under investigation. The best therapeutic strategy has not been defined.

OBJECTIVE

To perform a comprehensive patient-level analysis of all PTPR cases and identify their clinical features, treatment options, and prognostic factors.

METHODS

A search of the medical databases for case series and reports on PTPRs from January 2003 to June 2017 was performed. Data addressing PTPR's clinical presentation, imaging, treatment, and histological features were. Variables associated with the primary outcome of 36-mo survival were identified through Cox regression models.

RESULTS

The initial search yielded 1164 studies, of which 71 were included (60 case reports and 11 case series), containing 177 patients (mean age 33.0 ± 15.3 yr and 53.2% male). Intracranial hypertension and hydrocephalus prevailed as the clinical picture. Surgery was performed on 82.0% and gross total resection (GTR) was achieved on 71.4%. A total of 56.8% recurred after a median 29 mo (quartiles 10.5-45.5). The 36-mo survival rate was 83.5% (95% confidence interval [CI] 76.2-89.2%). Good functional outcomes (Glasgow Outcome Scale 4/5) were observed in 60.0%. The variables of interest were inconsistently reported and the multivariable analysis final sample was 133 patients. After adjustment for age, tumor size (each additional centimeter, hazard ratio [HR] 1.99, 95% CI 1.12-3.53, P = .019) and surgical treatment (HR 0.16, 95% CI 0.05-0.45, P = .001) were associated with 36-mo survival.

CONCLUSION

Tumor size and surgery are associated with improvement in 36-mo survival. We did not observe any significant benefits from GTR or adjuvant treatments.

Radiotherapy for papillary tumor of the pineal region: A systematic review of the literature

Papillary tumor of the pineal region (PTPR) is a rare neuroepithelial brain tumor, characterized by a high risk of local recurrence (greater than 70 % at 6 years). The aim of our study was to review the available literature on radiotherapy for PTPR in order to evaluate timings, schedules, outcomes and toxicities of this treatment modality. In our review, 72.4 % (84) of the patients diagnosed with PTPR received radiation therapy. There is heterogeneity in the dose prescription, ranging from 45 Gy (25 × 1.8 Gy) to 60 Gy (30 × 2 Gy) for 3D Conformal Radiation Therapy and from 12 Gy to 36 Gy for Stereotactic Radiosurgery. Being considered as a grade II or III tumor, PTPR should receive higher total radiation dose in the adjuvant setting. Our analysis showed a very limited treatment-related toxicity with an expected 10-y OS of 72.5 %. At 5-years from the diagnosis, about 60 % of the patients experienced a local recurrence, whereas at 10 years the rate is higher than 80 %. In the literature, conflicting data about radiotherapy for PTPR are reported, in particular regarding disease progression. Although radiotherapy represents a fundamental treatment in the management of PTPR, prospective studies are required to better define its impact on overall survival and progression-free survival.

Recurrent Pineocytomalike Papillary Tumor of The Pineal Region: A Case Report and Literature Review

BACKGROUND

Papillary tumors of the pineal region (PTPRs) are malignant World Health Organization grade II/III tumors; however, they may perfectly mimic benign tumors (e.g., pineocytomas [World Health Organization grade I]).

CASE DESCRIPTION

We present a case of a 28-year-old man with a 35-mm tumor of the pineal region. Considering the typical radiological and pathologic presentation, the tumor was first diagnosed as pineocytoma. However, despite first total resection, the tumor recurred after 7 years. The recurrent neoplasm was composed mainly of papillary structures with low-grade atypical cells positive for CKAE1/AE3 and CK18. This categorization led to the final diagnosis of PTPR. The patient underwent adjuvant radiotherapy, which vastly improved his neurologic condition and resulted in significant tumor regression.

CONCLUSIONS

This case exemplifies that PTPRs can perfectly mimic pineocytomas and simple staining for cytokeratins may warrant correct diagnosis and better treatment.

Nuclear CRX and FOXJ1 Expression Differentiates Non-Germ Cell Pineal Region Tumors and Supports the Ependymal Differentiation of Papillary Tumor of the Pineal Region

Papillary tumor of the pineal region (PTPR) is a neuroepithelial neoplasm first described in 2003. Despite the anatomic association of PTPR with the pineal gland, the features of these tumors resemble those of the ependymal circumventricular subcommissural organ (SCO) of the posterior third ventricle. Given the presumed distinct derivation of PTPR and pineal parenchymal tumors, we hypothesized that expression of lineage-specific transcription factors could distinguish these tumors and provide additional insight into the differentiation of PTPR. A broad series of pineal region samples was reviewed, including 7 benign pineal glands, 4 pineal cysts, 13 pineocytomas, 28 pineal parenchymal tumors of intermediate differentiation, 11 pineoblastomas, and 18 PTPR. All samples were evaluated by immunohistochemistry for expression of CRX, a master transcriptional regulator of photoreceptor differentiation expressed in pineal gland and retina and/or FOXJ1, a master transcriptional regulator of ciliogenesis expressed in normal ependymal cells and ependymal neoplasms. Diffuse nuclear CRX expression is present in 100% of pineal samples. FOXJ1 is negative in all pineal samples. CRX staining is present in 53% of PTPR, though expression is nearly always limited to rare cells. Diffuse nuclear FOXJ1 expression is present in 100% of PTPR. Fetal human SCO diffusely expressed FOXJ1 but was negative for CRX. Immunohistochemistry for FOXJ1 and CRX differentiates non-germ cell pineal region tumors with high sensitivity and specificity, including pineal parenchymal tumors and PTPR. Our findings support the hypothesis that PTPR have ependymal differentiation and are phenotypically more similar to SCO than pineal gland.

NHERF1/EBP50 and NF2 as diagnostic markers for choroid plexus tumors

The adaptor protein NHERF1 (Na/H exchanger-3 regulatory factor-1) and its associated ezrin-radixin-moesin-merlin/neurofibromin-2 (ERM-NF2) family proteins are required for epithelial morphogenesis and have been implicated in cancer progression. NHERF1 is expressed in ependymal cells and constitutes a highly sensitive diagnostic marker for ependymoma, where it labels membrane polarity structures. Since NHERF1 and ERM-NF2 proteins show polarized expression in choroid plexus (CP) cells, we tested their diagnostic utility in CP neoplasms. NHERF1 immunohistochemistry in 43 adult and pediatric tumors with papillary morphology revealed strong apical plasma membrane staining in CP papilloma (WHO grade I) and cytoplasmic expression in CP carcinoma (WHO grade III). Ezrin and moesin showed similar but less distinctive staining. NHERF1 also labeled papillary tumors of the pineal region in a microlumen and focal apical membrane pattern, suggestive of a transitional morphology between CP papilloma and ependymoma. CP tumors of all grades could be differentiated from metastatic carcinomas with papillary architecture by NF2, which showed polarized membranous staining in CP tumors. NHERF1 and NF2 immunohistochemistry showed enhanced sensitivity and specificity for CP tumors compared to commonly used markers, including cytokeratins and Kir7.1, emerging as reliable diagnostic tools for the differential diagnosis of papillary tumors of the central nervous system.

Papillary tumor of the pineal region: A case report and review of the literature

Papillary tumor of the pineal region (PTPR) was first described as a distinct tumor entity in 2003 and was introduced into the World Health Organization classification of central nervous system tumors in 2007. This tumor is rare and, to the best of our knowledge, only 7 cases have been reported in children <16 years of age, while the youngest documented patient was a 15-month-old boy. The present study reported a case of PTPR in a 10-year-old girl who underwent magnetic resonance imaging and surgical resection of tumors. Histological and immunohistochemical staining results were presented. Patients with PTPR require long-term follow-up, and the patient of the present study has continued to do well, with no recurrence of the tumor at the 15-month follow-up examination. In addition, a review of the literature on this unusual neoplasm was performed, along with discussion of their differential diagnosis.

Papillary tumor of the pineal region-report of three cases with literature review

Papillary tumor of the pineal region (PTPR) is a rare tumor of the pineal region. Not much is known about the pathogenesis, prognosis, and treatment protocol of this uncommon entity. We present three cases of PTPR with follow-up from 8 months to 98 months. All patients presented with headache and visual disturbance. One patient also had amenorrhea. Radiology revealed an heterogeneously enhancing mass arising from the pineal region with associated hydrocephalus. Histopathologically, all cases showed the papillary architecture, strong pan cytokeratin and cytokeratin 18 positivity, and faint positivity for synaptophysin and neuron-specific enolase. All cases received postoperative radiotherapy. One case showed tumor recurrence after 7 years. Other two cases did not show any recurrence till the last follow-up.