Tumors of the posterior third ventricular region in pediatric patients: The Indian perspective and a review of literature

Intraventricular Tumors: Surgical Considerations in Lateral and Third Ventricular Tumors

Management of lateral and third ventricular tumors has been a challenge for neurosurgeons. Advances in imaging and pathology have helped in a better understanding of the treatment options. Technical refinement of microsurgical technique and addition of endoscopy has enabled more radical excision of tumors, when indicated, and added more safety.A proper understanding of the pathology at various ages and treatment options is continuously evolving. Many pediatric tumors are amenable to conservative surgical methods with effective complementary treatments. However, radical surgery is required in many adults as the main treatment and for many benign tumors. Various intraventricular lesions encountered and their surgical management is reviewed here for their efficacy, safety, and outcome, encompassing changes in our practice over the last 20 years.

Neuroendoscopy in the management of pineal region tumours in children

INTRODUCTION

Pineal region tumours (PRTs) are more common in children and represent a wide variety of lesions. The practise of a radiation test dose is obsolete and a biochemical/histological diagnosis is recommended before further therapy. Many patients present with hydrocephalus. Advances in neuroendoscopic techniques have allowed safe and effective management of this obstructive hydrocephalus with an opportunity to sample cerebrospinal fluid (CSF) and obtain tissue for histopathology. Definitive surgery is required in less than a third. Endoscopic visualisation and assistance is increasingly used for radical resection, where indicated.

METHODOLOGY

Our experience of endoscopic surgery for paediatric PRTs from 2002 to 2021 is presented. All patients underwent MRI with contrast. Serum tumour markers were checked. If negative, endoscopic biopsy and endoscopic third ventriculostomy (ETV) were performed; and CSF collected for tumour markers and abnormal cells. For radical surgery, endoscope-assisted microsurgery procedures were performed to minimise retraction, visualise the extent of resection and confirm haemostasis.

RESULTS

M:F ratio was 2:1. The median age of presentation was 11 years. Raised ICP (88.88%) was the commonest mode of presentation. Nineteen patients had pineal tumours, one had a suprasellar and pineal tumour, one had disseminated disease, while six had tectal tumours. The ETB diagnosis rate was 95.45%, accuracy rate was 83.3% and ETV success rate was 86.96%.

CONCLUSION

Neuroendoscopy has revolutionised the management of paediatric PRTs. It is a safe and effective procedure with good diagnostic yield and allows successful concurrent CSF diversion, thereby avoiding major surgeries and shunt implantation. It is also helpful in radical resection of lesions, where indicated.

Management of mature pineal region teratomas in pediatric age group

PURPOSE

Mature pineal region teratomas differ from other pineal tumors in terms of their characteristic radiological appearance and their clinical outcome after gross total excision. Our aim is to share our clinical experience and treatment outcomes in pediatric patients with mature pineal region teratoma.

METHODS

In this retrospective study, we reviewed clinical, radiological, and surgical data of ten patients who had radiologically predicted diagnosis of pineal region teratoma and pathologically confirmed diagnosis of mature pineal region teratoma between years 2004 and 2017 in our clinic. Statistical analysis was performed with SPSS 20.

RESULTS

All patients were male. Ages of patients ranged between 5 and 17 (median age was 9.5). All of them presented with headache. Magnetic resonance imaging showed characteristic appearance of teratomas with variable degree of hydrocephalus. All patients had negative results for AFP and b-HCG levels. All patients had gross total resection of pineal tumor through occipital transtentorial approach with no permanent neurological deficit. Pathological results of all tumor samples were consistent with mature teratoma. None of them had adjuvant chemotherapy or radiotherapy. Follow-up periods ranged between 3 and 170 months (median follow-up period was 60.5 months). All patients are alive with no tumor recurrence.

CONCLUSIONS

Pediatric mature pineal region teratomas are benign tumors with characteristic MRI appearance and negative tumor markers. Their definitive treatment is gross total surgical excision. Occipital transtentorial approach is a safe procedure for treatment of pediatric mature pineal teratomas.

Intracranial germ cell tumors: a multi-institutional experience from three tertiary care centers in India

OBJECTIVE

Central nervous system germ cell tumors (CNS GCTs) are relatively rare neoplasms. Incidence of CNS GCTs in Western literature is low (0.3-0.6 %) as compared to East Asia (3-4 %). No large study is available on CNS GCTs from India.

METHODS

Intracranial GCT cases were retrieved from databases of three tertiary care institutes in India; clinicopathological data was reviewed.

RESULTS

Ninety-five intracranial GCT cases were identified, accounting for 0.43 % of CNS tumors. Median age was 12 years (range, birth to 48 years); male preponderance was noted (66 %). Most patients (86.3 %) were aged <18 years. Pineal location was most common (45 %) and was associated with male gender and age >14 years. Germinoma was the commonest histopathological type (63.2 %), followed by teratoma (20 %). Suprasellar location was associated with germinoma histology. Follow-up was available for 71 patients (median, 15 months). Of these, 48 received adjuvant chemotherapy and/or radiotherapy. At the last follow-up, 44 patients showed no evidence of disease. Age >10 years, male gender, pineal location, and germinoma histology were associated with favorable outcome.

CONCLUSION

This is the first multicentric study from India establishing that incidence of CNS GCT in India is similar to that in the West and differs from that in East Asian countries. However, similar to both, germinoma is the commonest histological type, and pineal location is most frequent. Studies on molecular alterations based on ethnicity and geographical location are necessary to provide clarity on differences in incidence. Attention needs to be focused on decreasing treatment heterogeneity and minimizing treatment-related morbidity and mortality, improving the cure rate of these highly treatable tumors.

Common molecularcytogenetic alterations in tumors originating from the pineal region

Tumors of the pineal region (PR) are rare and can be subdivided into four main histomorphological groups: Pineal-parenchymal tumors (PPT), germ cell tumors (GCT), glial tumors and miscellaneous tumors. The appropriate pathological classification and grading of these malignancies is essential for determining the clinical management and prognosis. However, an early diagnosis is often delayed due to unspecific clinical symptoms, and histological support is not always decisive to identify the diversity of tumors of the PR. The present study aimed to characterize 18 tumors of the PR using comparative genomic hybridization. All the tumors were primarily surgically resected without any previous irradiation or chemotherapy. In addition to chromosomal aberrations in PPT and different GCTs of the PR, the present study described, for the first time, the chromosomal changes in a few rare entities (solitary-fibrous and neuroendocrine tumors) of the PR. The tumors in the study, regardless of histology and World Health Organization grade, were characterized by frequent gains at 7, 9q, 12q, 16p, 17 and 22q, and losses at 13q. While the detection of chromosomal aberrations in these tumors appears not to be indicative enough of histological entities and their grade of malignancy, the present data may be of use to select genes of interest for higher resolution genomic analyses.

Incidence of pineal tumours. A review of the literature

The knowledge of the incidence of pineal tumours is important not only for diagnostic care but also for its therapeutic programme. We reviewed the incidence of pineal tumours reported in literature in an attempt to establish if a difference existed between pineal gland tumours and the pineal region tumours as different authors use both expressions to indicate the same thing. The rate of frequency of these tumours is useful to guide the therapeutic choice for patients as the decisional tree is completely different for either germ cell tumours, pineal gland tumours or pineal gliomas and eventually papillary tumours of the pineal region. According to the French Register of pineal tumours, true pineal tumours represent: 27% pineal parenchymal tumours (PPT), 27% germ cell tumours, 17% gliomas, 8% papillary tumours. True pineal gland tumours are represented by: pineocytomas - (13%), pineal parenchymal tumours with intermediary differentiation PTT-ID - (66%) and pinealoblastomas - (21%). There was no statistical difference found between the French register and the Lyon series concerning histological diagnosis. It seemed to us important to discover its true incidence by comparing the data published in the literature and to stress the utility of the French Register for these uncommon tumours not only for recording new histological cases but also to document clinical symptomatology, therapeutic programmes, length of follow-up and clinical results for each patient treated. A better understanding of their natural history and improved evaluation of different treatments and their complications should contribute to improve clinical results.

Peripheral primitive neuroectodermal tumor of the pelvis

The primitive neuroectodermal tumor (PNET) belongs to a group of highly malignant tumors and is composed of small round cells of a neuroectodermal origin. Categorized in the same tumor family as Ewing sarcoma, the PNET is most likely to occur in bones and soft tissues. However, a small number of PNET cases arising in the pelvis have been reported as well.

WE PRESENT THREE CASES OF PELVIC PNET

two cases in the ovary and one case in the broad ligament. The PNET often exhibits aggressive clinical behavior with worse outcomes than other small round cell tumors. The significant prognostic factors of the PNET include site of tumor, volume of neoplasm, and presence of metastasis. The treatment protocol is multimodal and includes local surgical treatment followed by chemotherapy. We herein describe three PNET cases as a rare entity in the pelvis. Pelvic PNETs should be included in the differential diagnosis of pelvic masses.