Microsurgical Treatment of Pineal Tumors: Anatomy and Techniques

Pineal region tumors are challenging lesions in terms of surgical accessibility and removal.1 The complexity is compounded by the infrequency and heterogeneity of pineal neoplasms.2,3 In Video 1, we present the case of a 39-year-old woman who presented with progressive headaches and vision impairment. She underwent microsurgical resection for a pineal parenchymal tumor of intermediate differentiation. We discuss the rationale, risks, and benefits of treatment for this patient, as well as provide a detailed overview of the alternative approaches that may be considered. Additionally, we discuss the unique anatomic considerations for each approach and include a virtual reality-compatible 3-dimensional fly-through to highlight the relationship between the tumor and relevant venous anatomy. The patient tolerated the procedure well with excellent neurologic outcome, and her follow-up imaging showed no evidence of tumor recurrence.

Papillary Tumors of Pineal Region: A Single-Center Experience in Management of 11 Cases

BACKGROUND

Papillary tumors of pineal region (PTPR) comprise a very rare subset of pineal region tumors that have been recently described. Literature on the management and outcome of PTPR is scarce owing to the rarity of these tumors. To address this lacuna, we analyzed our experience in management of PTPR.

METHODS

We retrospectively analyzed the outcome of 11 patients with histopathologically proven PTPR who underwent surgical excision at our center.

RESULTS

Mean patient age was 33.3 years (range, 12-45 years), and male-to-female ratio was 1.75:1. Headache was the most common presentation followed by visual disturbances, altered sensorium, Perinaud syndrome, and seizures. Cerebrospinal fluid diversion was required in 6 patients. Krause approach was the most common approach used for tumor excision (9/11 cases). There was no perioperative mortality. Two patients were lost to follow-up. In the remaining 9 patients, the average follow-up period was 45 months (range, 12-79 months). On first postoperative magnetic resonance imaging, 8 patients showed no evidence of residual tumor (gross total resection), while 1 patient had small residual tumor (near-total resection) that remained stable during follow-up. Four patients underwent adjuvant chemoradiotherapy. None of the patients developed recurrence during follow-up.

CONCLUSIONS

PTPR are a rare subgroup of pineal region tumors with distinct cells of origin but presentation similar to other pineal region tumors. Surgical resection constitutes the mainstay of management, and the extent of resection appears to be the most important determinant of prognosis. The role of adjuvant therapy still needs to be determined.

[Neurosurgical treatment of tumors of the pineal region - literature review and overview of cases at OMIII]

Pineal region tumors account for less than 1% of adult supratentorial tumors. Their treatment requires a multimodality approach. Previously, the treatment of choice was direct surgery, which is associated with high surgical risk. Advances in minimally invasive techniques and onco-radiotherapy offer a safe and multimodal personalized therapy. The aim of our study was to describe the practice of our Institute based on combined endoscopic and radiotherapy techniques. We performed a retrospective clinical study. We processed data from 23 adult patients who underwent endoscopic third ventricle fenestration and pineal tumor biopsy between 2014 and 2023. Descriptive statistics, t-test, Fisher's exact test and Kaplan-Meier analysis were performed. Clinical improvement with endoscopic intervention was achieved in 78.3% of cases. Significant increase in preoperative performance status was observed in the postoperative period (p=2.755e-5), and radiotherapy resulted in regression or stable disease. Our results suggest a safe treatment with good clinical outcome and an excellent alternative to direct surgery.

Surgical corridor formation by minimally invasive lateral occipital infracortical supra-/transtentorial (OICST) approach in pineal region tumor surgery: A review of 11 cases

INTRODUCTION

The pineal region is a hard-to-reach part of the brain. There is no unequivocal opinion on the choice of a surgical approach to the pineal region. The surgical approaches described differ in both trajectory (infra- and supratentorial, interhemispheric) and size of craniotomy. They have advantages and disadvantages. The minimally invasive lateral occipital infracortical supra-/transtentorial (OICST) approach we have described has all the advantages of the standard supratentorial approach and minimizes its disadvantages, namely, compression and contusion of the occipital lobe. The minimally invasive craniotomy and small surgical corridor facilitate that.

METHODS

We describe 11 consecutive patients with various pineal region tumors (7 cases of pineal cysts, 2 cases of pinealocytoma, 1 case of medulloblastoma, and 1 case of meningioma) who were operated on in our hospital using the lateral OICST approach. Preoperative planning was performed using Surgical Theater®. The surgical corridor was formed using a retractor made from half of a syringe shortened according to the length of the surgical corridor. Preoperative lumbar drain was used.

RESULTS

The pineal region tumors were completely resected in all cases. The mean craniotomy size was 2.22 × 1.79 cm. No long-term neurological deficits were reported.

CONCLUSIONS

The use of semicircular retractors and intraoperative CSF drainage via a lumbar drain allows to form a small surgical corridor to the pineal region via minimally invasive craniotomy. This reduces traction and traumatization of the occipital lobe, as well as minimizes intra- and postoperative risks.

Primary Gamma Knife Radiosurgery for pineal region tumors: A systematic review and pooled analysis of available literature with histological stratification

Pineal region tumors (PTs) represent extremely rare pathologies, characterized by highly heterogeneous histological patterns. Most of the available evidence for Gamma Knife radiosurgical (GKSR) treatment of PTs arises from multimodal regimens, including GKSR as an adjuvant modality or as a salvage treatment at recurrence. We aimed to gather existing evidence on the topic and analyze single-patient-level data to address the efficacy and safety of primary GKSR. This is a systematic review of the literature (PubMed, Embase, Cochrane, Science Direct) and pooled analysis of single-patient-level data. A total of 1054 original works were retrieved. After excluding duplicates and irrelevant works, we included 13 papers (n = 64 patients). An additional 12 patients were included from the authors' original series. A total of 76 patients reached the final analysis; 56.5% (n = 43) received a histological diagnosis. Confirmed lesions included pineocytoma WHO grade I (60.5%), pineocytoma WHO grade II (14%), pineoblastoma WHO IV (7%), pineal tumor with intermediate differentiation WHO II/III (4.7%), papillary tumor of pineal region WHO II/III (4.7%), germ cell tumor (2.3%), neurocytoma WHO I (2.3%), astrocytoma WHO II (2.3%) and WHO III (2.3%). Presumptive diagnoses were achieved in the remaining 43.5% (n = 33) of cases and comprised of pineocytoma (9%), germ cell tumor (6%), low-grade glioma (6%), high-grade glioma (3%), meningioma (3%) and undefined in 73%. The mean age at the time of GKSR was 38.7 years and the mean lesional volume was 4.2 ± 4 cc. All patients received GKSR with a mean marginal dose of 14.7 ± 2.1 Gy (50% isodose). At a median 36-month follow-up, local control was achieved in 80.3% of cases. Thirteen patients showed progression after a median time of 14 months. Overall mortality was 13.2%. The median OS was not reached for all included lesions, except high-grade gliomas (8mo). The 3-year OS was 100% for LGG and pineal tumors with intermediate differentiation, 91% for low-grade pineal lesions, 66% for high-grade pineal lesions, 60% for germ cell tumors (GCTs), 50% for HGG, and 82% for undetermined tumors. The 3-year progression-free survival (PFS) was 100% for LGG and pineal intermediate tumors, 86% for low-grade pineal, 66% for high-grade pineal, 33.3% for GCTs, and 0% for HGG. Median PFS was 5 months for HGG and 34 months for GCTs. The radionecrosis rate was 6%, and cystic degeneration was observed in 2%. Ataxia as a presenting symptom strongly predicted mortality (odds ratio [OR] 104, p = .02), while GCTs and HGG histology well predicted PD (OR: 13, p = .04). These results support the efficacy and safety of primary GKSR treatment of PTs. Further studies are needed to validate these results, which highlight the importance of the initial presumptive diagnosis for choosing the best therapeutic strategy.

Neurosurgical application of pineal region tumor resection with 3D 4K exoscopy via infratentorial approach: a retrospective cohort study

BACKGROUND

The pineal region tumors are challenging for neurosurgeons and can lead to secondary hydrocephalus. The introduction of the exoscope has provided clinical interventions with high image quality and an ergonomic system for pineal region tumor operations. In this study, the authors describe the exoscopic approach used to facilitate the surgical resection of pineal region tumors and relieve hydrocephalus.

MATERIALS AND METHODS

In this retrospective cohort study, we consecutively reviewed the clinical and radiological data of 25 patients with pineal region lesions who underwent three-dimensional exoscopic tumor resection at a single center.

RESULTS

The patient cohort consisted of 16 males and 9 females, with an average age of 34.6 years (range, 6-62 years; 8 cases aged ≤18). Pathological examination confirmed eight pineal gland tumors, four gliomas, nine germ cell neoplasms, two ependymomas, and two metastatic tumors. Preoperative hydrocephalus was present in 23 patients. Prior to tumor resection, external ventricular drainage (EVD) with Ommaya reservoir implantation was performed in 17 patients. Two patients received preoperative endoscopic third ventriculostomy (ETV), and five patients received a ventriculoperitoneal (VP) shunt, including one who received both procedures. Gross total resection was achieved in 19 patients (76%) in the 'head-up' park bench position using the exoscope. Eight patients (31.6%) with third ventricle invasion received subtotal resection, mainly in glioma cases, which was higher than those without invasion (0%), but not statistically significant ( P =0.278, Fisher's exact test). No new neurological dysfunction was observed after surgery. Two patients (8%) developed intracranial and pulmonary infections, and two patients (8%) suffered from pneumothorax. Hydrocephalus was significantly relieved in all patients postoperatively, and four patients with relapse hydrocephalus were cured during the long-term follow-up. Postoperative adjuvant management was recommended for indicated patients, and a mean follow-up of 24.8±14.3 months showed a satisfied outcome.

CONCLUSIONS

The exoscope is a useful tool for pineal region tumor resection and hydrocephalus relief, particularly with posterior third ventricle invasion, as total resection could be achieved without obvious complication. The special superiority of the exoscope for the indicated pineal region tumors should be highlighted.

The sub-occipital transtentorial approach for pineal region tumors: how I do it

BACKGROUND

Two major approaches exist for the surgical removal of pineal region tumors: the supracebellar infratentorial and the sub-occipital transtentorial.

METHODS

We present the Lyon's technique of the sub-occipital transtentorial approach for pineal region tumors and our tricks to avoid complications. The principle is to expose the pineal region under the occipital lobe and not through the interhemispheric fissure.

CONCLUSIONS

The sub-occipital transtentorial approach is a direct, extra cerebral, safe, and effective way to access tumors of the pineal region.

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.

Results of the treatment of pineal tumors in children: the Lyon experience

INTRODUCTION

Pineal tumors are rare and their incidence is of 1% among all pediatric tumors of the central nervous system. Patient survival depends on the histology, the extension of the surgical removal, and the efficacy of the complementary treatment (chemotherapy and cranio-spinal irradiation), as well as the age of the patient.

MATERIALS AND METHODS

In this study, we analyzed 151 pediatric patients treated for pineal tumors from 1997 to 2020 in Lyon, France. All patients were recorded in the French Register of Pineal tumors, which has been centralized and maintained in Lyon since 2010.

RESULTS

Our analysis shows that benign tumors have an overall positive prognosis with total surgical removal. Concerning pineal parenchymal tumors, pinealoblastomas have a poor prognosis , especially in children less than three years old. A new pathological classification system allows for a better stratification of patient risk within different groups of patients with pineal tumors. It is also important to note that the identification of DICER 1 syndrome in families with pinealoblastomas warrant further medical investigation. Patients with Germ Cell Tumors have more favorable outcomes, with a global survival rate of 87 % and a pure germinoma survival rate of almost 97%. When analyzing the prognosis of pineal gland gliomas, otherwise known as tectal plate gliomas, pilocytic astrocytomas had a promising prognosis. Otherwise, prognosis of other tectal plate gliomas are related to the grade of malignancy and the efficacy of complementary treatment. Lastly, papillary tumors need a complete removal for the best chance of survival, and Atypical teratoid/ rabdoid tumors (AT/TR) still have a bad prognosis, regardless of surgical resection.

CONCLUSIONS

Our results show that, with regards to pediatric pineal region tumors, there are still areas in prognostic indicators that need to be improved. Similarly, these pathologies need to be treated via a multidisciplinary approach to improve a patient's survival rate and their quality of life.

Pediatric pineal region tumors: institutional experience of surgical managements with posterior interhemispheric transtentorial approach

PURPOSE

Resecting pineal region tumors in children is often challenging. Several approaches have been proposed and practiced. A personal series of pediatric pineal region tumors resected through craniotomy with posterior interhemispheric occipital transtentorial (OT) approach are reviewed. We present the surgical techniques, pitfalls, and their results.

MATERIAL AND METHODS

Eighty patients ranging in age from 3 months to 21 years old, and treated over 3 decades were reviewed. Hydrocephalus caused the main presenting symptoms and was noted in 74 patients. It was treated prior to the craniotomy for tumor resection with endoscopic third ventriculostomy (ETV) in 33, external ventricular drainage in 26, and precraniotomy shunt in 15. Nine patients had ETV together with endoscopic biopsy. All patients had a parieto-occipital craniotomy in a prone position. Through a tentorial section, a gross total resection of the tumor was attempted except for germinomas.

RESULTS

The tumor pathology showed 32 germ cell tumors (GCT), 22 benign astrocytomas, 13 pineal parenchymal tumors, 5 ATRTs, 3 papillary tumors, and 5 others. Of GCTs, 18 were teratomas. The extent of resection consisted of 55 gross total resections, 13 subtotal resections, 10 partial, and 2 biopsies with one postoperative death. Hemiparesis in 2, cerebellar ataxia in another 2, and hemiballismus in 1 were transient and improved over time. One had permanent hemisensory loss and another patient had bilateral oculomotor palsy. Postoperative homonymous hemianopia occurred in 2 patients but subsided over a short period of time. Parinaud's sign was noted in 24 patients, of which 16 were transient.

CONCLUSION

The posterior interhemispheric OT approach provides a safe route and comfortable access to the pineal region in children. A great majority of postoperative neurological complications are the results of direct manipulations of the midbrain at tumor resection. Identification and preservation of the tumor-brain interface are of paramount importance. GCTs other than teratomas are treated with neoadjuvant chemotherapy and may eliminate the need for craniotomy. Exophytic midbrain JPAs are amenable to resection.

Temporal profile of serum melatonin levels in paediatric pineal tumours subjected to surgery: newer insights

INTRODUCTION

Pineal tumours (PTs) are rare and histologically variable. Serum melatonin is a well-known product of this gland, albeit with uncertain clinical implications vis-à-vis its utility as a potential tumour marker. In particular, the temporal profile of serum melatonin during the disease course remains unclear and infrequently studied.

METHODS

Ten children with pineal tumours were prospectively studied over 2 years. Midnight serum melatonin levels were estimated before and after surgery (6-week postoperatively) and at the time of clinical-radiological progression. Different clinical, radiological, histological and treatment variables were correlated with the mean change in the pre- and postoperative serum melatonin levels using statistical methods.

RESULTS

Histopathologically, 5 of these cases (50%) were pineal cell tumours, while the rest were tumours of non-pineal cell origin. The mean preoperative serum melatonin level was 94.9 pg/ml (range 20-397 pg/ml), while the mean postoperative level was 69.6 pg/ml (range 45-156 pg/ml; in one case, the levels became non-detectable). Tumour histology (p = 0.04) and gender (p = 0.03) correlated with high preoperative serum levels. While the change in overall mean value did not have any statistical significance (effect size 0.29, p value 0.340), postoperative serum melatonin elevation was significant in tumours of non-pineal cell origin (large effect size 0.93, p value 0.004).

CONCLUSION

The serum melatonin may be affected by age, gender and symptom duration. However, the dynamic of serum melatonin in the perioperative period is largely dependent on the cell of origin of the PT.

Second-look surgery for pineal region tumors

PURPOSE

Surgical resection of pineal region tumors is challenging because of close proximity to the vein of Galen draining system and the quadrigeminal plate. Surgical resection usually is performed through the narrow corridor by piecemeal resection and en bloc resection is difficult in cases of large tumors. Moreover, in cases of hypervascular tumors, surgical resection through the narrow corridor could entail massive intraoperative bleeding. The effectiveness of neoadjuvant chemotherapy and second-look surgery for pineal region tumors for maximal safe resection was evaluated.

METHODS

Retrospective institutional review of pediatric patients with pineal region tumors who underwent second look surgery after neoadjuvant chemotherapy was performed.

RESULTS

Nine patients underwent surgical resection after neoadjuvant chemotherapy over the period of September 2017 to February 2022. The mean age was 7.7 years (ranged from 1.4 to 15.3 years). Three patients underwent partial resection via open craniotomy, and 6 underwent endoscopic biopsy as an initial surgery. The histopathological diagnoses were germ cell tumors in 5 patients (yolk sac tumors in 2, germinoma in 2, choriocarcinoma in 1), /rhabdoid tumor (AT/RT) in 2, medulloblastoma in 1, and high-grade glioneuronal tumor in 1. After several courses of chemotherapy, the second-look surgery was performed. The tumor volume was reduced in 8 patients (89%) after chemotherapy except for 1 case of growing teratoma syndrome. The tumor was extended laterally to the ambient cistern in 2 patients, and posteriorly to the tentorial surface of the cerebellum in 3 patients. The lesion was approached through occipital transtentorial approach in 8 patients and infratentorial supracerebellar approach in 1. Intraoperatively, the high vascularity of the tumor was not observed in all cases. Gross total resection (8 patients, 89%) or near total resection (1, 11%) was achieved in all cases. No complications were observed postoperatively in all cases. Eight patients subsequently underwent additional chemo-radiation therapy according to the initial diagnosis. All patients are alive with no evidence of recurrence with a mean follow-up of 33 months.

CONCLUSIONS

Neoadjuvant chemotherapy and second-look surgery for pediatric pineal region tumors was considered to be effective in reducing the tumor volume and vascularity, which facilitates the safe maximal tumor resection.

Radiation-induced Desmoid Tumor Development in the Radiotherapy Field in a Child With Pineoblastoma: A Case Report

Although treatment-related secondary malignancies are rare, they are important problems after the treatment of childhood malignant diseases. Irradiation-induced sarcomas are the development of sarcoma different from the primary tumor after a latent period of ≥3 years or more in the radiotherapy field. Desmoid tumor is extremely rare as irradiation-induced tumor. A 7.5-year-old girl was referred to our hospital after a subtotal mass excision for a solid lesion with a cystic component located in the pineal gland. Pathologic examination revealed pineoblastoma. After surgery, craniospinal radiotherapy, and chemotherapy consisting of vincristine, cisplatin, and etoposide were performed. Painless swelling in the left parieto-occipital region ~75 months after the end of the treatment developed in the patient. A mass was detected in the intracranial but extra-axial region by radiologic imaging methods. Due to the total removal of the mass and the absence of a tumor in the surgical margins, she was followed up without additional treatment. The pathologic diagnosis was a desmoid tumor. She was followed up disease free for ~7 years after the primary tumor and ~7 months after the secondary tumor. Treatment-related desmoid tumor development after treatment for a central nervous system tumor in a child is extremely rare.

Pineal Parenchymal Tumor of Intermediate Differentiation and DICER1 Syndrome: A Case Report

DICER1 syndrome is a rare inherited tumor predisposition syndrome associated with an increased risk for several malignant and benign tumors. We present a patient with pineal parenchymal tumor of intermediate differentiation who was found to have a germline pathogenic variant in DICER1 gene. Pineoblastoma is a known DICER1-related tumor; however, the association between pineal parenchymal tumor of intermediate differentiation and DICER1 mutation is rare with only 1 recent large molecular study that has reported this association. This report adds to the evolving tumor spectrum of DICER1 and highlights the importance of molecular evaluation of pediatric brain tumors, for both therapeutic decisions and long-term surveillance.

The Minimally Invasive Lateral Occipital Infracortical Supra-/Transtentorial Approach in Surgery of Lesions of the Pineal Region: A Possible Alternative to the Standard Approaches

OBJECTIVE

The pineal region is an anatomical region that is difficult to access surgically, especially when it comes to removing neoplasms. Four main surgical approaches to this region are used as standards nowadays: infratentorial supracerebellar, occipital supra-/transtentorial, interhemispheric, and transventricular approaches. All methods have both advantages and disadvantages and are associated to any extent with intra- and postoperative risks. We have developed a lateral minimally invasive occipital infracortical supra-/transtentorial (OICST) approach, which retains the advantages of the standard occipital transtentorial approach while improving tumor exposure and minimizing its disadvantages.

METHODS

We describe 7 consecutive cases of successful complete removals of pineal tumor formations of various quality and size (3 pineal cysts, 2 pineocytomas, 1 meningioma, 1 medulloblastoma) using the OICST approach developed by us. Preoperative 3-dimensional and virtual reality-modeling and the use of a special retractor also contributed to reducing the size of the surgical approach.

RESULTS

All patients underwent surgery for removal of a lesion in the pineal region and suffered from no new and permanent neurological deficits postoperatively. The mean size of the craniotomies was 2.3 × 1.85 cm. The minimally invasive approach developed by us carries the advantages of the standard occipital transtentorial approach, but minimizes its disadvantages. The main disadvantage of the standard occipital approach is excessive retraction of the occipital lobe, which is frequently associated with visual neurological deficits. Also, with occipital approach, the Rosenthal vein lying along the surgical corridor is frequently not good visible since the tumor is approached from its tip rather than side which limits the overview of the surgical field and can pose a risk. Damage to this vein can cause infarction of the basal ganglia. By approaching the pineal region from more laterally the size of the craniotomy can significantly be reduced, excessive retraction of the occipital lobe can be avoided and the risk of damage to large deep veins can be minimized. The cosmetic outcome with a small skin incision of only about 3 cm is also a very good side effect of this minimally invasive technique.

CONCLUSIONS

The minimally invasive lateral OICST approach described by us can be successfully used in the surgery of pineal neoplasms. Reducing the size of the craniotomy does not limit the possibility of complete removal of tumors of various sizes and tissue consistency, and also minimizes the risks of both intra- and postoperative complications.

Supracerebellar Infratentorial Approach for a Malignant Pineal Region Tumor Mimicking a Cavernous Malformation

A man in his early 20s presented with diplopia. Imaging revealed a pineal region hemorrhagic lesion, suggestive of cavernous malformation.^1-6 The patient underwent an endoscopic third ventriculostomy and was transferred to our institution. In the sitting position, he underwent a supracerebellar infratentorial approach. Gross total resection was achieved without new neurological deficits. Pathologic diagnosis was consistent with a mixed germ cell tumor. The patient was referred to the radiation oncology department. Gravity retraction of the cerebellum was achieved with the supracerebellar infratentorial approach in the sitting position, torcular craniotomy exposed the major sinuses, and drainage of cerebrospinal fluid widened the surgical corridor and facilitated resection of this lesion (Video 1). Histopathological findings are critical to establish the correct diagnosis because magnetic resonance imaging findings can be misleading. The patient provided written informed consent for the procedure.

Metastases in the Pineal Region: A Systematic Review of Clinical Features, Management Strategies, and Survival Outcomes

BACKGROUND

Pineal region metastases are rare but often cause severe neurologic deficits. Surgical resection and chemoradiotherapy can provide therapeutic benefit. We investigated the literature to analyze clinical characteristics, management strategies, and survival of adult patients with pineal region metastases.

METHODS

PubMed, Embase, Scopus, and Cochrane were searched following the PRISMA guidelines, including studies reporting clinical outcomes of patients with pineal region metastases. Clinical presentation, management, and survival were reviewed.

RESULTS

We included 31 studies comprising 47 patients. Lung cancer (29.8%) and carcinomas of unknown origin (14.9%) were the most frequent primary tumors. In 48.9% of patients, symptomatic pineal metastases preceded primary tumor diagnosis. Headache (67.4%) and confusion (46.5%) were the most common symptoms. Parinaud syndrome (46.5%) and hydrocephalus (87.2%) were noted. Biopsy (65.9%) was preferred over resection (34.1%), and shunting strategies used were endoscopic third ventriculostomy (43.9%) and ventriculoperitoneal (26.8%). Eleven patients (32.3%) received adjuvant chemotherapy and 32 (68%) received radiotherapy. Posttreatment improvement in symptoms (56.6%) and hydrocephalus (80.5%) were noted. In patients who received adjuvant chemotherapy/radiotherapy, significant improvement in posttreatment performance status occurred with both biopsy (P < 0.001) and resection (P = 0.007). No survival differences were reported between surgery and biopsy (P = 0.912) or between complete and partial resection (P = 0.220). Overall survival was neither influenced by surgical approach (P = 0.157) nor by shunting strategy (P = 0.822). Mean follow-up was 8 months and median overall survival 3 months. Only 2 cases (4.8%) of pineal metastasis showed recurrence.

CONCLUSIONS

Pineal region metastases carry significant morbidity. Biopsy or surgical resection, combined with adjuvant chemotherapy/radiotherapy and/or shunting, may significantly improve performance status.

Pineal teratoma with nephroblastic component in a newborn male: Case report and review of the literature

Neonatal germ cell tumors are rare and comprise both benign and malignant neoplasms. Teratoma with nephroblastoma is a malignant subset defined pathologically by the presence of nephroblastoma and teratoma elements. Although teratoma with nephroblastoma is most often found in the kidney, 24 of 59 reported cases are associated with extrarenal locations, such as the mediastinum or retroperitoneum. To our knowledge, this is the first patient in the literature with intracranial/pineal teratoma with nephroblastoma, which was managed with staged transcranial approaches resulting in gross total resection and no adjuvant therapy (surveillance observation imaging). We further augmented the patient's management by comprehensive genomic profiling of the tumor to better understand the molecular biology and explore options for targeted therapy.

Molecular subgrouping of primary pineal parenchymal tumors reveals distinct subtypes correlated with clinical parameters and genetic alterations

Tumors of the pineal region comprise several different entities with distinct clinical and histopathological features. Whereas some entities predominantly affect adults, pineoblastoma (PB) constitutes a highly aggressive malignancy of childhood with a poor outcome. PBs mainly arise sporadically, but may also occur in the context of cancer predisposition syndromes including DICER1 and RB1 germline mutation. With this study, we investigate clinico-pathological subgroups of pineal tumors and further characterize their biological features. We performed genome-wide DNA methylation analysis in 195 tumors of the pineal region and 20 normal pineal gland controls. Copy-number profiles were obtained from DNA methylation data; gene panel sequencing was added for 93 tumors and analysis was further complemented by miRNA sequencing for 22 tumor samples. Unsupervised clustering based on DNA methylation profiling separated known subgroups, like pineocytoma, pineal parenchymal tumor of intermediate differentiation, papillary tumor of the pineal region and PB, and further distinct subtypes within these groups, including three subtypes within the core PB subgroup. The novel molecular subgroup Pin-RB includes cases of trilateral retinoblastoma as well as sporadic pineal tumors with RB1 alterations, and displays similarities with retinoblastoma. Distinct clinical associations discriminate the second novel molecular subgroup PB-MYC from other PB cases. Alterations within the miRNA processing pathway (affecting DROSHA, DGCR8 or DICER1) are found in about two thirds of cases in the three core PB subtypes. Methylation profiling revealed biologically distinct groups of pineal tumors with specific clinical and molecular features. Our findings provide a foundation for further clinical as well as molecular and functional characterization of PB and other pineal tumors, including the role of miRNA processing defects in oncogenesis.

Pineoblastoma segregates into molecular sub-groups with distinct clinico-pathologic features: a Rare Brain Tumor Consortium registry study

Pineoblastomas (PBs) are rare, aggressive pediatric brain tumors of the pineal gland with modest overall survival despite intensive therapy. We sought to define the clinical and molecular spectra of PB to inform new treatment approaches for this orphan cancer. Tumor, blood, and clinical data from 91 patients with PB or supratentorial primitive neuroectodermal tumor (sPNETs/CNS-PNETs), and 2 pineal parenchymal tumors of intermediate differentiation (PPTIDs) were collected from 29 centres in the Rare Brain Tumor Consortium. We used global DNA methylation profiling to define a core group of PB from 72/93 cases, which were delineated into five molecular sub-groups. Copy number, whole exome and targeted sequencing, and miRNA expression analyses were used to evaluate the clinico-pathologic significance of each sub-group. Tumors designated as group 1 and 2 almost exclusively exhibited deleterious homozygous loss-of-function alterations in miRNA biogenesis genes (DICER1, DROSHA, and DGCR8) in 62 and 100% of group 1 and 2 tumors, respectively. Recurrent alterations of the oncogenic MYC-miR-17/92-RB1 pathway were observed in the RB and MYC sub-group, respectively, characterized by RB1 loss with gain of miR-17/92, and recurrent gain or amplification of MYC. PB sub-groups exhibited distinct clinical features: group 1-3 arose in older children (median ages 5.2-14.0 years) and had intermediate to excellent survival (5-year OS of 68.0-100%), while Group RB and MYC PB patients were much younger (median age 1.3-1.4 years) with dismal survival (5-year OS 37.5% and 28.6%, respectively). We identified age < 3 years at diagnosis, metastatic disease, omission of upfront radiation, and chr 16q loss as significant negative prognostic factors across all PBs. Our findings demonstrate that PB exhibits substantial molecular heterogeneity with sub-group-associated clinical phenotypes and survival. In addition to revealing novel biology and therapeutics, molecular sub-grouping of PB can be exploited to reduce treatment intensity for patients with favorable biology tumors.

Risk-adapted therapy and biological heterogeneity in pineoblastoma: integrated clinico-pathological analysis from the prospective, multi-center SJMB03 and SJYC07 trials

Pineoblastoma is a rare embryonal tumor of childhood that is conventionally treated with high-dose craniospinal irradiation (CSI). Multi-dimensional molecular evaluation of pineoblastoma and associated intertumoral heterogeneity is lacking. Herein, we report outcomes and molecular features of children with pineoblastoma from two multi-center, risk-adapted trials (SJMB03 for patients ≥ 3 years; SJYC07 for patients < 3 years) complemented by a non-protocol institutional cohort. The clinical cohort consisted of 58 patients with histologically diagnosed pineoblastoma (SJMB03 = 30, SJYC07 = 12, non-protocol = 16, including 12 managed with SJMB03-like therapy). The SJMB03 protocol comprised risk-adapted CSI (average-risk = 23.4 Gy, high-risk = 36 Gy) with radiation boost to the primary site and adjuvant chemotherapy. The SJYC07 protocol consisted of induction chemotherapy, consolidation with focal radiation (intermediate-risk) or chemotherapy (high-risk), and metronomic maintenance therapy. The molecular cohort comprised 43 pineal parenchymal tumors profiled by DNA methylation array (n = 43), whole-exome sequencing (n = 26), and RNA-sequencing (n = 16). Respective 5-year progression-free survival rates for patients with average-risk or high-risk disease on SJMB03 or SJMB03-like therapy were 100% and 56.5 ± 10.3% (P = 0.007); respective 2-year progression-free survival rates for those with intermediate-risk or high-risk disease on SJYC07 were 14.3 ± 13.2% and 0% (P = 0.375). Of patients with average-risk disease treated with SJMB03/SJMB03-like therapy, 17/18 survived without progression. DNA-methylation analysis revealed four clinically relevant pineoblastoma subgroups: PB-A, PB-B, PB-B-like, and PB-FOXR2. Pineoblastoma subgroups differed in age at diagnosis, propensity for metastasis, cytogenetics, and clinical outcomes. Alterations in the miRNA-processing pathway genes DICER1, DROSHA, and DGCR8 were recurrent and mutually exclusive in PB-B and PB-B-like subgroups; PB-FOXR2 samples universally overexpressed the FOXR2 proto-oncogene. Our findings suggest superior outcome amongst older children with average-risk pineoblastoma treated with reduced-dose CSI. The identification of biologically and clinically distinct pineoblastoma subgroups warrants consideration of future molecularly-driven treatment protocols for this rare pediatric brain tumor entity.

Genomic profile of a primary squamous cell carcinoma arising from malignant transformation of a pineal epidermoid cyst

Malignant transformation of intracranial epidermoid cysts is a rare occurrence. We present the second case of such an event occurring in the pineal region and the first case sent for detailed genomic profiling. MRI demonstrated two lesions: a cyst in a quadrigeminal cistern with restricted diffusion on DWI-weighted images and an adjacent, peripherally enhancing tumor with cerebellar infiltration. Both the lesions were completely resected with a small residual of the epidermoid cyst. The final pathology of both lesions was consistent with epidermoid cyst and squamous cell carcinoma (SCC), respectively. The tumor specimen was sent for comprehensive genomic profiling which revealed stable microsatellite status and loss of CDKN2A/B, MTAP (exons 2-8), and PTEN (exons 6-9). Although reports of primary SCC originating from the epidermoid cyst have been previously described, this is the first description of the genomic profile of such a tumor.

CNS germinoma with extensive calcification: An unusual histologic finding

INTRODUCTION

Intratumoral calcification is a feature that is more often observed in pineal parenchymal tumour than germinoma. We describe a 13-year-old male with pineal region germinoma demonstrating extensive intratumoral calcification.

CASE REPORT

He presented with worsening headache that was associated with fatigue, nausea and vomiting. Radiologic examination revealed a multilobular mass in the pineal region with internal calcifications. Biopsy showed a pure germinoma with unusually extensive calcification.

DISCUSSION

Although a diagnosis may be suggested with a careful evaluation of imaging, there is no pathognomonic pattern. Thus, histologic verification is necessary for most pineal region masses.

[Surgical approaches to pineal region - review article]

INTRODUCTION

The pineal region is a deep-seated part of the brain surrounded by highly eloquent structures. Differential diagnosis of space-occupying lesions in this region encompasses pineal gland cysts, pineal gland tumours, metastases, germ cell tumours, meningiomas, gliomas, hemangioblastomas and neuroectodermal tumours. A treatment strategy is based mainly on tumour anatomical characteristics and histological type. Except germinatous tumours, a surgical excision is the treatment of choice.

METHODS

Microsurgical approaches: The microsurgical supracerebellar-infratentorial approach is an essential approach to the pineal region. Despite certain risks, it allows a straightforward and completely extracerebral approach with a minimal cerebellar retraction. The other basic approach is the microsurgical occipital-transtentorial approach that is advantageous in patients with a supratentorial tumour extension or a steep tentorium. The interhemispheric-transcallosal approach and the transcortical-transventricular approach are possible options in selected cases.Endoscopic approaches: The neuroendoscopy provides a minimally invasive method to perform a tumour biopsy and to treat hydrocephalus in one session. Stereotactic biopsy: The stereotactic needle biopsy represents an alternative to the endoscopic biopsy in patients without hydrocephalus and in patients with dorsally located lesions inaccessible from the third ventricle.

CONCLUSION

Modern neurosurgery offers a rich variety of surgical approaches to the pineal region. The complexity of space-occupying lesions in this region requires an individualised treatment, a prudent preoperative planning and a meticulous surgical technique.

Mature teratoma of the pineal region in the paediatric age group: A case report and review of the literature

INTRODUCTION

Intracranial teratomas account for 0.5% of all intracranial tumours and 2-4% of intracranial tumours in children. However, in terms of tumours of the pineal area, the exact incidence is not ascertained. Although, it is noted that 50-60% of central nervous system (CNS) germ cell tumours are found in the pineal gland. The degree of difficulty in the sampling of lesions in the pineal gland during biopsy emphasizes the importance of correlating the imaging studies, histopathologic findings, and serum and cerebrospinal fluid (CSF) tumour markers.

CASE REPORT

This case report is that of a 9-year-old male who presented with frontal headache of eight days, with associated photophobia, nausea and vomiting, and diplopia. Biopsy with intraoperative navigation was done and the specimen was referred for histopathologic evaluation. The biopsy showed findings consistent with a mature teratoma with no histologic findings of an immature component or secondary somatic malignancy. Comparison of the pre-operative and post-operative multiaxial cranial CT scan showed findings that was consistent with a residual lesion. This was correlated with the pre-operative serum tumour markers which showed alpha-fetoprotein of 22.5 ng/mL and beta-HCG of 1.0 mIU/mL(IU/L), and the post-operative tumour markers of the cerebrospinal fluid that showed alpha-fetoprotein of 3.28 ng/mL and beta-HCG of 18.9 mIU/mL (IU/L).

CONCLUSION

A review of the literature and comparison with current case in relation to the histopathologic, serum and CSF findings, and imaging studies was done to better understand the mechanism of this lesion.

p53 Restoration in Induction and Maintenance of Senescence: Differential Effects in Premalignant and Malignant Tumor Cells

The restoration of p53 has been suggested as a therapeutic approach in tumors. However, the timing of p53 restoration in relation to its efficacy during tumor progression still is unclear. We now show that the restoration of p53 in murine premalignant proliferating pineal lesions resulted in cellular senescence, while p53 restoration in invasive pineal tumors did not. The effectiveness of p53 restoration was not dependent on p19(Arf) expression but showed an inverse correlation with Mdm2 expression. In tumor cells, p53 restoration became effective when paired with either DNA-damaging therapy or with nutlin, an inhibitor of p53-Mdm2 interaction. Interestingly, the inactivation of p53 after senescence resulted in reentry into the cell cycle and rapid tumor progression. The evaluation of a panel of human supratentorial primitive neuroectodermal tumors (sPNET) showed low activity of the p53 pathway. Together, these data suggest that the restoration of the p53 pathway has different effects in premalignant versus invasive pineal tumors, and that p53 activation needs to be continually sustained, as reversion from senescence occurs rapidly with aggressive tumor growth when p53 is lost again. Finally, p53 restoration approaches may be worth exploring in sPNET, where the p53 gene is intact but the pathway is inactive in the majority of examined tumors.

Clinical, Pathological, and Surgical Outcomes for Adult Pineoblastomas

INTRODUCTION

Pineoblastomas are uncommon primitive neuroectodermal tumors that occur mostly in children; they are exceedingly rare in adults. Few published reports have compared the various aspects of these tumors between adults and children.

METHODS

The authors report a series of 12 pineoblastomas in adults from 2 institutions over 24 years. The clinical, radiologic, and pathologic features and clinical outcomes were compared with previously reported cases in children and adults.

RESULTS

Patient age ranged from 24 to 81 years, and all but 1 patient exhibited symptoms of obstructive hydrocephalus. Three patients underwent gross total resection, and subtotal resection was performed in 3 patients. Diagnostic biopsy specimens were obtained in an additional 6 patients. Pathologically, the tumors had the classical morphologic and immunohistochemical features of pineoblastomas. Postoperatively, 10 patients received radiotherapy, and 5 patients received chemotherapy. Compared with previously reported cases, several differences were noted in clinical outcomes. Of the 12 patients, only 5 (42%) died of their disease (average length of survival, 118 months); 5 patients (42%) are alive with no evidence of disease (average length of follow-up, 92 months). One patient died of unrelated causes, and one was lost to follow-up. Patients with subtotal resections or diagnostic biopsies did not suffer a worse prognosis. Of the 9 patients with biopsy or subtotal resection, 4 are alive, 4 died of their disease, and 1 died of an unrelated hemorrhagic cerebral infarction.

CONCLUSIONS

Although this series is small, the data suggest that pineoblastomas in adults have a less aggressive clinical course than in children.

Diffusion characteristics of pediatric pineal tumors

BACKGROUND

Diffusion weighted imaging (DWI) has been shown to be helpful in characterizing tumor cellularity, and predicting histology. Several works have evaluated this technique for pineal tumors; however studies to date have not focused on pediatric pineal tumors.

OBJECTIVE

We evaluated the diffusion characteristics of pediatric pineal tumors to confirm if patterns seen in studies using mixed pediatric and adult populations remain valid.

MATERIALS AND METHODS

This retrospective study was performed after Institutional Review Board approval. We retrospectively evaluated all patients 18 years of age and younger with pineal tumors from a single institution where preoperative diffusion weighted imaging as well as histologic characterization was available.

RESULTS

Twenty patients (13 male, 7 female) with pineal tumors were identified: seven with pineoblastoma, four with Primitive Neuroectodermal Tumor (PNET), two with other pineal tumors, and seven with germ cell tumors including two germinomas, three teratomas, and one mixed germinoma-teratoma. The mean apparent diffusion coefficient (ADC) values in pineoblastoma (544 ± 65 × 10⁻⁶ mm²/s) and pineoblastoma/PNET (595 ± 144 × 10⁻⁶ mm²/s) was lower than that of the germ cell tumors (1284 ± 334 × 10⁻⁶ mm²/s; p < 0.0001 vs pineoblastoma). One highly cellular germinoma had an ADC value of 694 × 10⁻⁶ mm²/s.

CONCLUSION

ADC values can aid in differentiation of pineoblastoma/PNET from germ cell tumors in a population of children with pineal masses.

Long Survival of Primary Pineal Melanoma with Radiation Treatment Only

Pineal gland tumors in adults account for about 0.4 to 1 % of all intracranial tumors. A wide variety of tumors can occur in the pineal gland. The most common are the pineal parenchymal tumors (pineocytomas, pineoblastomas, and pineal parenchymal tumors of intermediate differentiation), germ cell tumors, and glial tumors. Uncommonly in the pineal gland one may encounter a metastatic tumor, a meningioma or a melanoma.

We here report a case of primary pineal gland melanoma with prolonged survival of 56 weeks after radiotherapy alone. To our knowledge, this is the first reported case of prolonged survival after radiotherapy alone, without surgical intervention or chemotherapy. Contrary to previous reports, our case demonstrates that a pineal melanoma with leptomeningeal dissemination can still yield a better survival with radiation treatment only.

An unusual location for a choroid plexus papilloma: the pineal region

PURPOSE

Choroid plexus papillomas (CPP) are rare benign neoplasms of the central nervous system that occur most often in children during the first decade of life. They occur most often in the lateral ventricle. It is extremely rare for a CPP to occur in the pineal region. We describe the case of a child with a CPP located in the pineal region, who was initially diagnosed with obstructive hydrocephalus by cranial computed tomography (CT).

METHODS

A 9-year-old female patient presented with complaints of visual disturbance, nausea, and vomiting. Magnetic resonance imaging (MRI) showed a poor contrast-enhanced pineal-localized lesion. Anatomical variations within the patient caused her surgery to proceed using a supratentorial-occipital interhemispheric approach.

RESULTS

The tumor was totally removed, and a histological examination revealed the tumor to be a typical CPP. The patient received follow-up neurological and ophthalmologic examinations at 3, 6, 9, 12, 24, and 36 months postoperatively, which demonstrated her progressive improvement.

CONCLUSIONS

CPPs may have a wide range of locations and resulting symptoms. However, the pineal region is a rarely encountered location, particularly for pediatric patients. It is of great value to correctly differentiate neoplasms such as germ cell tumors, pineocytomas, meningiomas, and astrocytomas, so that patients receive the correct diagnosis and treatment approach.

Solitary fibrous tumor of the central nervous system: report of 2 cases and review of literature

Solitary fibrous tumors (SFTs) rarely occur in the central nervous system (CNS). Involvement of the brainstem and pineal gland is rarely recorded. Herein, we represent 2 cases of SFTs and firstly report SFT of the pineal gland. Cranial MR imaging showed isointense to hypointense signal intensity, and marked enhancement. Microscopically, the tumors showed characteristic "patternless-pattern" architecture. Elongated tumour cells formed fascicles alternating with hypocellular densely collagenous stroma. Immunohistochemistry for CD34, BCL2, and CD99 favors the definitive diagnosis of SFT. It is difficult to predict prognosis in patients with intraventricular SFT. In general, complete surgical resection may offer the best chance of a favorable clinical outcome.

[A case of glioblastoma multiforme in the pineal region with intraventricular hemorrhage]

INTRODUCTION

Glioblastoma multiforme (GBM) is a very rare type of tumor involving the pineal region. No case of pineal region GBM with tumoral hemorrhage has ever been reported. Here, we present the first such case report.

CASE REPORT

A 65-year-old man presented with sudden-onset disturbance of consciousness. CT revealed intraventricular hemorrhage and acute hydrocephalus. The patient was treated by an emergent operation for ventricular drainage. MRI with contrast media showed a heterogeneous enhanced area in the pineal region. The patient underwent endoscopic biopsy surgery and a third ventriculostomy for non-communicating hydrocephalus. The pathological diagnosis was high-grade glioma, indicating the need for tumor removal via the occipital transtentorial approach. The tumor was removed subtotally and radiation and chemotherapy courses were then started.

CONCLUSION

Pineal GBM with tumoral hemorrhage has never been reported before. Endoscopic operations are useful for rapid decision making prior to radical surgery.

[Pineal anlage tumor in a 8-month-old boy. The first case reported in Spanish language]

BACKGROUND

The pineal anlage tumor is a very infrequent malign neoplasm. Even though it has been documented in literature, it is not listed yet in the World Health Organization's last nervous system classification (2007). It is a primitive pineal tumor with neuroepithelial and ectomesenchyme differentiation. Due to its low frequency, the understanding of its biological behavior and a suitable treatment are incomplete. In a search performed in PubMed with the term pineal anlage tumor, only seven informed cases were identified between 1989 and 2011.

CLINICAL CASE

An 8-month-old infant was brought to medical attention because he had a progressive enlargement of the cephalic perimeter, and convergent strabismus of two months of evolution. A pineal tumor was identified. The histology showed glial tissue, ganglia cells, pigmented neuroepithelium and striate muscle cells. A ventriculoperitoneal derivation was done to diminish hydrocephalic pressure and also to led the complete surgical resection. The patient was treated with two courses of chemotherapy with carboplatine, ifosfamide and mesna. One year after the treatment, the patient is asymptomatic.

CONCLUSIONS

This is the first case reported in Spanish language. Given that it is a really infrequent tumor, it could be misdiagnosed as teratome, melanotic or mesoblastic medulloblastoma, or a melanotic neuroectodermal tumor of childhood (melanotic prognoma).

Cellular pleomorphism in papillary tumors of the pineal region

Papillary tumor of the pineal region (PTPR) is a recently recognized entity. We present the pathologic findings of two cases of PTPR as examples, and discuss the presence of cellular pleomorphism in these tumors. Patient 1 is a 48-year-old man with a pineal region mass. The tumor had unique biphasic patterns, papillary/pseudopapillary areas, and increased mitotic activity. Juxtaposed areas had marked pleomorphism, including nuclear enlargement, smudgy chromatin, nuclear pseudoinclusions, and cytoplasmic vacuolation. Mitoses were absent in these areas. Immunohistochemical staining revealed strong S100 expression. CAM 5.2 and CK18 were strongly positive in a patchy fashion. MIB1 labeling indices were high in classic PTPR regions but very low in pleomorphic areas. Patient 2 was a 35-year-old male with a pineal region tumor characterized by papillary architecture and overall cellular monotony, rare mitoses, and pleomorphism as a more isolated finding, with associated nuclear enlargement and crowding. S100 and CAM 5.2 labeling were present, and MIB1 labeling index was very low throughout the tumor. We discuss the pathologic and phenotypic features of PTPR. Variable pleomorphism may be present, reflected in size variation and nuclear hyperchromasia, but was not accompanied by increased proliferative activity in these cases, suggesting a degenerative phenomenon.

Clinical and neurophysiological changes in patients with pineal region expansions

In the last 20 years neurological and neurosurgical follow up of our patients with pineal region expansions (118 patients) pointed to certain clinical and neurophysiological regularities. We performed retrospective study which included 84 patients with pineal region expansions in the period from 1992 to 2009. The study included 55 women and 29 men, mean age 30.08 +/- 13.93 years, with positive brain magnetic resonance imaging (MRI)--70 patients (83.4%) had simple pineal gland cysts, and 14 patients (16.67%) had expansive process in pineal region with compressive effect. All patients had headache, while 32 patients (38%) had epileptic phenomena--primary generalized seizures. Patients had common electroencephalography (EEG) pattern with paroxysmal discharges of 3Hz (or more than 3 Hz) spike-and-wave complexes. Operation with supracerebellar infratentorial approach was performed in 70 patients. In most of our patients indication for the operation was established based on the size of the cyst (15 mm or more), with the signs of compression on the quadrigeminal plate and compression of the surrounding veins, which could result in seizures and EEG changes verified in our group of patients. Pathohistological analysis revealed pineocytomas in 11 cases (15.71%), pinealoblastomas in 2 cases (2.86%), one case of teratoma (1.43%), while 56 patients had pineal gland cysts (80%). Following surgery clinical condition improved in all patients--patients became seizure-free and headaches significantly decreased. Other symptoms including diplopiae, nausea, vomiting, vertigo as well as blurred vision also disappeared. There were no complications after surgical procedures. This study points to often appearance of seizures that clinically and neurophysiologically present as primary generalized epilepsy in patients with pineal region expansions. Our hypotheses are that mass effect on the surrounding veins that affects normal perfusion, compressive effect on the quadrigeminal plate and the aqueduct of the midbrain, hemosiderin deposists, as well as secretion disturbances of anticonvulsive agent melatonin can be involved in the pathogenesis of seizures. We suggest to perform high resolution brain MRI with special demonstration of pineal region in all young patients that have seizures and specific EEG changes.

Pineal region tumors: simultaneous endoscopic third ventriculostomy and tumor biopsy

OBJECTIVE

Advances in neuroendoscopy have accommodated the development of intraventricular techniques that enhance the management of multiple disease processes. Tumors of the pineal region are amenable to endoscopic management in that they are accessible through the third ventricle and commonly cause hydrocephalus that can be alleviated by endoscopic third ventriculostomy (ETV). We describe the indications for and procedure of simultaneous ETV and biopsy of pineal region tumors, as well as the clinical features favoring different approaches to this procedure.

METHODS

The current literature on endoscopic management of pineal region tumors and the senior author's clinic experience with current techniques are reviewed.

RESULTS

Simultaneous tumor biopsy with ETV following initial evaluation with tumor markers and imaging can be accomplished using a single or dual entry approach. The choice of approach is dependent on multiple clinical factors including massa intermedia size, goals of surgery, degree of hydrocephalus, and the relationship between the tumor and massa intermedia.

CONCLUSIONS

Simultaneous ETV and tumor biopsy is a valuable technique that can be used to manage hydrocephalus and establish diagnosis in patients with newly diagnosed pineal region tumors, potentially avoiding traditional craniotomy and ventriculoperitoneal shunt placement. It is favored as an early step in the management of patients with marker-negative tumors.

Endoscopic supracerebellar infratentorial retropineal approach for tumor resection

BACKGROUND

Lesions located in the pineal region represent a surgical challenge. Multiple approaches to this region have been described, each with its advantages and disadvantages. We report the first application of the endoscopic supracerebellar infratentorial approach for complete resection of a pineal tumor. Unlike transventricular endoscopy, this technique poses no risk to the fornices and can be applied independent of ventricular size.

CASE DESCRIPTION

A 21-year-old man sought treatment for diplopia. Magnetic resonance images of brain revealed a heterogeneous, contrast-enhancing mass that originated from the pineal gland. This tumor exerted the mass effect on the tectum and invaded to the bilateral dorso-medial thalamus and hypothalamus but caused no obstructive hydrocephalus. The results of a cytological study of the cerebrospinal fluid, alpha-fetoprotein, and beta-human chorionic gonadotropin were negative. The patient was referred for the surgical work-up.

TECHNIQUE

The patient was positioned in the semi-sitting position. The supracerebellar infratentoria corridor was accessed through two paramedian burr holes, which provided natural by-gravity cerebellar traction. The excellent illumination and magnification without sacrificing the inferior occipital sinus could be achieved with the aid of the endoscope. The pineal tumor was resected completely via the full-endoscopic approach. Postoperatively, the patient's diplopia resolved completely, and his hospital course was uneventful.

CONCLUSIONS

Taking the advantages of the endoscope and peculiar supracerebellar infratentoria corridor, we could successfully remove the gross-total tumor without violating the critical neurovascular structures. Moreover, this approach can be performed regardless of the size of the ventricle. Consequently, it is an excellent minimally invasive surgical option for resection of symptomatic pineal tumor.

Bifocal intracranial germinoma: a retrospective analysis of treatment outcomes in 20 patients and review of the literature

PURPOSE

Bifocal germinoma (BFG) is a rare intracranial neoplasm for which the choice of radiation therapy (RT) field is controversial. Some believe that BFG represents disseminated disease requiring craniospinal irradiation (CSI), whereas others believe that BFG represents localized disease and advocate for more limited fields.

METHODS AND MATERIALS

We analyzed 20 BFG patients at our institutions with classic bifocal lesions (pineal gland and suprasellar region). In addition, we identified 60 BFG patients from the literature. The RT fields, use of chemotherapy and extent of disease were recorded and analyzed for each patient.

RESULTS

There were 55 patients with bifocal lesions only (Group I), and 25 with bifocal lesions plus ventricular and/or CSF positive disease (Group II). The 5-year progression-free survival was 95% for Group I and 80% for Group II. In Group I, there were no failures in patients receiving CSI (n = 11), two spinal failures in those treated with more limited RT fields without chemotherapy (n = 17), and one spinal failure with chemotherapy (n = 23). In Group II, there were no failures in patients receiving CSI (n = 11), but four spinal failures were observed in patients receiving more limited RT fields with chemotherapy (n = 13); 1 patient who received whole-brain RT without chemotherapy experienced failure in the spine and brain.

CONCLUSIONS

CSI is associated with excellent PFS in BFG. In Group I BFG patients, omission of spinal irradiation appears to be a reasonable approach, especially when chemotherapy is used. Patients with Group II BFG are best treated with CSI.

[Pathological features and origin of primary pineal mixed germ cell tumors]

OBJECTIVE

To investigate the origin of mixed germ cell tumors in the pineal region based on the image data, surgical findings and pathological examination of the tumor.

METHODS

The preoperative CT and magnetic resonance imaging (MRI) findings and tumor specimens were retrospectively analyzed in 15 cases of pineal mixed germ cell tumors confirmed by postoperative histological examination between January 2000 and September 2010.

RESULTS

Radiographic examination of the tumor revealed calcification in 12 cases, cystic changes in 10 cases, and the presence of lipid in 5 cases. On the anteroposterior images, the tumors appeared round or elliptic with smooth edge in 6 cases, and showed irregular shape with multiple processes on the edge in 9 cases. Surgical exploration found all the tumors located in the the suprapineal recess enclosed by the arachnoidal envelope of the Galen vein. Pathologically, 13 specimens contained germinoma component, 9 contained teratoma component, 4 had embryonic carcinoma component, 3 had choriocarcinoma component, 7 showed yolk sac tumor component, and 3 showed rhabdomyoma component. Germinoma components were found on the tumor margin in 7 specimens, and intermingled germinoma and other components were found in 10 specimens.

CONCLUSION

Pineal mixed germ cell tumor originates from the residue germ cells around the pineal gland, and most likely evolves from single primordial germ cells.

Histopathological patterns of papillary tumour of the pineal region

Papillary tumour of the pineal region (PTPR) is a rare neoplasm that has been formally included in the 2007 WHO classification of central nervous system tumours. The critical diagnosis of this neoplasm is often difficult because of its similarity to other primary or secondary papillary lesions of the pineal region, including parenchymal pineal tumours, papillary ependymoma, papillary meningioma, choroid plexus papilloma and metastatic papillary carcinoma. We present the variability of the histopathological pattern in three cases of PTPR. All cases showed predominant epithelial-like morphology but with various degrees of papillary formation and intensity of cellular pleomorphism. One tumour was highly cystic and exhibited cellular sheets containing vessels covered by several layers of uniform columnar to cuboidal tumour cells. The second tumour showed distinct papillae covered by layers of polymorphous cells with atypical, often hyperchromatic nuclei. Numerous cells displayed foamy, eosinophilic or clear, sometimes vacuolated cytoplasm. The third case consisted of solid cellular areas composed of pseudostratified columnar cells, most often arranged in perivascular pseudorosette formations. The cells lining papillary structures exhibited marked polymorphism with atypical, often plump nuclei. Mitotic figures were rare and areas of necrosis were observed only in one case. Immunohistochemical staining showed diffuse immunoreactivity for neuron-specific enolase, S-100 protein, cyto-keratin and vimentin. Focal reaction for synaptophysin and chromogranin A and epithelial membrane antigen (EMA) were observed. The tumours lacked expression of GFAP. The Ki-67 labelling index was relatively low but its focal increase was noted in two cases. The final diagnosis of PTPR was based on both predominant papillary morphology and immunohistochemical results. PTPR should be considered in diagnosis of pineal tumours but their natural history, therapeutic strategy and prognosis remain controversial.

Low-grade oligodendroglioma of the pineal gland: a case report and review of the literature

BACKGROUND

Gliomas are a very rare subtype of pineal region tumours, whereas oligodendrogliomas of the pineal region are exceedingly rare, since there have been only 3 cases of anaplastic oligodedrogliomas reported this far.

METHODS-RESULTS

We present a case of a low-grade oligodendroglioma arising in the pineal gland of a 37 year-old woman. The patient presented with diplopia associated with a cystic pineal region mass demonstrated on MRI. Total resection was performed and histological examination showed that the cystic wall consisted of tumour cells with a central nucleus a perinuclear halo and minimal pleomorphism. Immnunohistochemical analysis showed that these cells were diffusely positive for CD57, and negative for GFAP, CD10, CD99, cytokeratins, neurofilaments and synaptophysin. FISH analysis was performed in a small number of neoplastic cells, which were not exhausted after immunohistochemistry and did not reveal deletion of 1p and 19q chromosome arms. However, the diagnosis of a low grade oligodendroglioma of the pineal gland was assigned.

CONCLUSION

Although the spectrum of tumours arising in the pineal gland is broad, the reports of oligodendrogliomas confined to this location are exceedingly rare, and to the best of our knowledge there is no report of a low-grade oligodendroglioma. However, they should be added in the long list of tumours arising in the pineal gland.

Pineal parenchymal tumor of intermediate differentiation with papillary features: a continuum of primary pineal tumors?

Pineal parenchymal tumors comprise a rare group of primary neoplasms of the pineal gland. We describe a case involving a 29-year-old woman who presented with signs and symptoms of hydrocephalus secondary to a pineal region tumor obstructing the third ventricle. Surgical resection was performed and pathological analysis revealed a novel diagnosis consistent with a pineal parenchymal tumor of intermediate differentiation (PPTID) with transition to a papillary tumor of the pineal region (PTPR). To our knowledge, this particular pineal region tumor pathology has not yet been reported in the literature and highlights the continuum with which primary pineal tumors exist. We provide a review of the existing literature on pineal region tumors, specifically PTPR and PPTID, and offer insight into the management of these rare neoplasms.