Objectives: A pineal region tumor is an uncommon deepseated, heterogeneous group of mass lesions of the brain, the pineal region is the origin of lesions with a highly diverse histopathology. The purpose of this communication is to present results of our experience in treating patients with these neoplasms.
Journal of military pharmaco-medicine no2-2018 RESULT TREATMENT OF PINEAL REGION TUMORS ON 45 PATIENTS WITH THE INFRATENTORIAL SUPRACEREBELLAR APPROACH Nguyen Van Hung*; Dong Van He** SUMMARY Objectives: A pineal region tumor is an uncommon deepseated, heterogeneous group of mass lesions of the brain, the pineal region is the origin of lesions with a highly diverse histopathology The purpose of this communication is to present results of our experience in treating patients with these neoplasms Subjects and methods: From 2010 to 2016, 112 patients were operated at Department of Neurosurgery, Vietduc Hospital The tumors were removed in 112 cases In this paper, we present results of microsurgery on 45 patients with pineal region lesions who were operated by infratentorial supracerebellar (ITSC) approach On the basis of the MRI and CT, we divided all pineal tumors into five groups: 1) Small tumors [less than 2.5 cm in diameter] mainly located in the quadrigeminal cistern; 2) Midsized tumors (4 cm in diameter) located in both the posterior part of the third ventricle and quadrigeminal cistern; 3) Large tumors (4 cm in diameter) occupied the pineal region and expanded into lateral ventricle in some cases; 4) Giant tumors (6 cm in diameter) made up nearly the whole third ventricle, expanding into the fourth and lateral ventricles Results: In 45 patients, a significant obstructive hydrocephalus was diagnosed preoperatively and a ventriculoperitoneal (VP) shunt was seen in 12 patients (26.67%) and 43 patients (73.33%) with endoscopic third ventriculostomy were performed month before Total tumor removal was achieved in 18 patients (40%), subtotal removal in 23 patients (51.11%) and partial removal in patients (8.89%) Pathohistological examination revealed 11 pineocytomas (24.44%), germinomas (20%), pineoblastomas (4.44%), astrocytomas (15.56%) and astrocytompilocytic, epidermoid cysts, yolk sack tumors Conclusions: The infratentorial supracerebellar approach provides a direct midline view to the pineal region between the dorsal cerebellum and tentorium These results confirm that surgery in the pineal region, especially using infratentorial supracecebellar approach, can be accomplished with relatively low morbidity and mortality Benign pineal tumors should be cured with surgery alone Malignant tumors should be treated with aggressive resection followed with irradiation and chemotherapy * Keywords: Pineal region tumors; Infratentorial supracerebellar approach INTRODUCTION Pineal region lesions are rare and uncommon deepseated tumors of the brain occupying 0.4% to 1% of adult brain tumors and these tumors are approximately 10 times more common in children than in adults and constitute 3% to 11% of childhood brain tumors [1, 2] * 103 Military Hospital ** Vietduc Hospital Corresponding author: Nguyen Van Hung (hungpttk103vn@gmail.com) Date received: 01/09/2017 Date accepted: 18/01/2018 148 Journal of military pharmaco-medicine no2-2018 Pineal tumors are a heterogeneous group of mass lesions originating in or located adjacent to the pineal gland and represent a spectrum of neoplasms ranging from benign to malignant The three major categories include germ cell tumors, pineal parenchymal cell tumors and the supporting tissue neoplasms [2] Before the microsurgical techniques, most authors advocated surgical conservatism because of an operative mortality from 30 to 70% and morbidity of up to 65% after surgery [4, 5, 6, 7, 8] Recent advances in neuroradiology CT, MRI, microneurosurgical techniques, modern neuroanesthesia and postoperative intensive care have led to more encouraging surgical results Now surgical tumors are removed with microsurgery and fractionated radiation therapy, which allows an overall mortality of less than 5% and a 5-year survival rate of 60 to 75%, the mortality of direct surgery has been reduced to under 5% and morbidity rate down to a minimal level [9, 10, 11] Outcome analysis of surgical strategies for pineal lesions are hindered by the small number of patients and the retrospective design of nearly all studies [4, 9] We report the surgical treatment outcome for 45 patients with pineal region lesions who have been applied infratentorial supracerebellar (ITSC) approach alone We have chosen an open surgical approach in order to achieve the pathohistologically exact diagnosis and possible total lesion removal SUBJECTS AND METHODS Subjects From 2010 to 2016, 112 patients were operated at Department of Neurosurgery, Vietduc Hospital The tumor was removed in 112 cases In this paper, we present treatment results of 45 patients with pineal region lesions who were operated by infratentorial supracerebellar approach Methods * Study design: - A retrospective clinical evaluation of patients with pineal region tumors was performed - A prospective study with surgical procedure: Microsurgery of pineal region tumors was performed by infratentorial supracerebellar approach Infratentorial supracerebellar approach is a midline incision made extending down to approximately C2 and up to the region of the lambdoid suture, above the external occipital protuberance The craniotomy should extend just above the inferior margin of lateral sinuses and the torcular A bilateral symmetric craniotomy with a free bone flap is performed above the foramen magnum rim After semioval incision of the dura below the lateral sinuses is made, some bridging veins between the cerebellum and the tentorium are cauterized and divided With the patient in the sitting position, the cerebellum drops down by gravity and provides to 1.5 cm of space between its surface and the tentorium This allows a relatively easy access over the 149 Journal of military pharmaco-medicine no2-2018 superior surface of one or both cerebellar hemispheres to the pineal region (figure 1) tumor compression or infiltration of the midbrain, the third ventricle walls and the hypothalamus as impaired oculomotor function such as upward gaze palsy and other variations of Parinaud’s syndrome… - Preoperative diagnostic studies: An analysis of the MRI and CT with pathologically proven pineal region tumors was performed, focusing on the relationship between the tumor and adjacent anatomic structures, the tumor size and its predominant expansion On the basis of these data, we divided all pineal tumors into four groups: 1) Small tumors [less than 2.5 cm in diameter] was mainly located in the quadrigeminal cistern; 2) Midsized tumors (2.5 - 4.0 cm in diameter) was sited in both the posterior part of the third ventricle and quadrigeminal cistern; 3) Large tumors (4 - cm in diameter) occupied the pineal region and expanded into lateral ventricle in some cases; 4) Giant tumors (diameter > cm) made up nearly the whole third ventricle, expanding into the fourth and lateral ventricles Figure 1: Pineal region tumor and infratentorial supracerebellar approach * Assessment of results: - Preoperative clinical signs: The clinical manifestations of the pineal tumors were attributable to a number of phenomena, including increased intracranial pressure because of obstructive hydrocephalus, 150 - Postoperative complications: Bleeding in the subdural or epidural effusions, inflammation (meningoencephalitis), significant risk of the oculomotor dysfunction… An assessment of the quality of life of all patient groups with a mean Karnofsky performance status score * Statistical analysis: All statistical analyses were performed using SPSS 16.0 software for Windows (SPSS, Inc., Chicago IL) A p-value < 0.05 was considered to be statistically significant Journal of military pharmaco-medicine no2-2018 RESULTS AND DISCUSSION Demographic characteristics of the patients treated by endoscopic third ventriculostomy (ETV) Preoperative diagnostic studies There were 21 male and 24 female patients Median age was 24.4 years (5 - 65 years) Mean follow-up was 26 months (4 - 48 months) Preoperative diagnostic evaluation consisted of a medical history, physical examination, detailed neurological examination and neuroradiological studies Table 1: Types of pineal region tumors CT and MRI of the brain revealed information about tumor localization and extension CT-scans were obtained for 26 out of the 45 patients MRI scans were performed in 45 patients We divided all pineal tumors into five groups: Small tumors with diameter ≤ 2.5 cm: case (2.22%); midsized tumors 2.5 - cm in diameter: 19 cases (42.22%); large tumors - cm in diameter: 22 cases (48.89%); giant tumors: > cm in diameter: 03 cases (6.67%) The maximum tumor size varied from 24 to 97 mm (median 42 mm) MRI showed the exact diagnosis of the localization of tumors and differentiation among blood, CSF, fat and calcium within tumors Also, MR angiography provided important information about the very complex deep venous system in pineal region [11] Tumor type Male Female Total Germinoma Pineocytoma 11 Pineoblastoma 2 Astrocytoma Pilocytic Epidermoid cyst 3 Yolk-sac tumor Menengimas Total 21 24 45 Preoperative clinical signs The most important clinical symptoms were related to the effects of increased intracranial pressure Obstructive hydrocephalus was detected in 45 patients (100%), headache was present in all patients (100%), vomiting was encountered in 40 patients (88.89%) Blurred vision was present in 21 patients (46.67%) Parinaud's syndrome was observed in 12 patients (26.67%), seizure was present in 18 patients (40%), diplopia was seen in 12 patients (26.67%) Glasgow coma score (GCS) - was achieved in patients (8.69%) at admission due to acute hydrocephalus These patients came to hospital by emergency and were Surgical treatment Several operative approaches to the pineal region are available Two approaches are rarely used, which are Dandy's transcallosal approach and Van Wagenen's transcortical transventricular approach [10, 11] Nowadays, two approaches to the pineal region are widely used They are Poppen-Yasargil occipital interhemispheric approach and KrauseStein infratentorial supracerebellar approach [12] The optimal approach for a specific 151 Journal of military pharmaco-medicine no2-2018 patient depends on the anatomical features of the tumor Also, the surgeon’s level of experience and comfort with each approach should be considered The surgical removal of the tumor and opening the posterior third ventricle can relieve the obstructive hydrocephalus The infratentorial supracerebellar approach was used in all patients in a sitting position, supine position The surgical procedure was done as described [8, 10] Although it has been reported that the sitting position is no longer in use due to the high incidence of venous air embolism, we have maximally reduced the possibility of venous air embolism following the standardized [8] In 45 patients, a significant obstructive hydrocephalus was diagnosed preoperatively and a ventriculoperitoneal shunt was seen in 12 patients (26.67%) and 33 patients (73.33%) were performed endoscopic third ventriculostomy month before To date, performing the endoscopic third ventriculostomy seems to be the best option in patients with obstructive hydrocephalus [12] The extent of lesion removal was graded as total, subtotal and partial Total tumor removal was achieved in 18 patients (40%), subtotal in 23 patients (51.11%) and partial in patients (8.89%) Totally removed tumors in our series were pineocytomas and symptomatic pineal cyst The number of benign pineal cysts is increasing due to improved neuroradiological diagnostic methods [8, 10] In our study, patients with pineal cysts who were operated had a median cyst size of 20 x 15 mm and persistent symptoms 152 Pathohistology According to the classification of World Health Organization, tumors in this series are divided into four main groups: germ cell tumors, pineal parenchymal tumors, glial tumor, and miscellaneous Pathohistological examination revealed 11 pineocytomas (24.44%), germinomas (20%), pineoblastomas (4.44%), astrocytomas (15.56%), and astrocytompilocytic, epidermoid cysts, yolk sack tumors The histological diagnosis was summarized in table Patients with malignant pineal lesions (germinomas, pineoblastomas, yolk sac tumor…) underwent irradiation and/or chemotherapy according to standardized protocol [7, 9] All benign lesions were completely removed Surgical results, complications and outcome The postoperative survival was 93.33%, postoperative mortality accounted for 6.67% After 3.6 months, KPS I + II of survival patients was good 46.32% of cases were completely cured by MRI or CT-scan There were cases of perioperative mortality (6.67%) Overall mortality was seen in patients (20%) during follow-up care from 38.7 ± 11.6 months patients died, among which four patients with germinomas and two patients with pineoblastomas, two patients with Yolk-sac tumor, and developed astrocytomas Three patients had postoperative seizures that were couped with antiepileptic drugs Journal of military pharmaco-medicine no2-2018 Four patients experienced meningitis and were treated with systemic antibiotic administration There were three patients with a cerebrospinal fluid fistula who needed wound revision and plastic of the dura Other complications included hemiparesis and diabetes insipidus Postoperative sequelae included vision disorders (26 patients = 57.78%), double vision (17 patients = 37.78%) CONCLUSIONS The infratentorial supracerebellar approach provides a direct midline view to the pineal region between the dorsal cerebellum and tentorium Its main disadvantage is hard-to-access to larger tumors and tumors with lateral extension These results confirm other literature reports that surgery in the pineal region, especially using infratentorial supracecebellar approach, can be accomplished with relatively low morbidity and mortality Benign pineal tumors should be cured with surgery alone Malignant tumors should be treated with aggressive resection followed with irradiation and chemotherapy Pure germinomas, which are exquisitely radiosensitive can be cured by conventional radiation therapy alone REFERENCES Abay E.O, Laws E.R, Grand G.L et al Pineal tumors in children and adolescents J Neurosurg 1981, 55, pp.889-895 Chan H.S, Humpreys R.P, Hendrick E.B et al Primary intracranial choriocarcinoma A report of two cases and review of the literature Neurosurgery 1984, 15, pp.540-545 Cumins F.M, Taveras J.M, Schlesinger E.B Treatment of gliomas of the third ventricle and pinealomas With special reference to the value of radiotherapy Neurology 1960, 10, pp.1031-1036 Dandy W.E Operative experience in cases of pineal tumor Arch Surg 1936, 33, pp.19-46 Poppen J.L, Marino R Jr Pinealomas and tumors of the posterior portion of the third ventricle J Neurosurg 1968, 28, pp.357-364 Jenkin R.D.T, Simpson W.J.K, Keen C.W Pineal and suprasellar germinomas Results of radiation treatment J Neurosurg 1978, 48, pp.99-107 Obrador S, Soto M, Gutierrez Diaz J.A Surgical management of tumors of the 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Experience with a palliative method J Neuro-Surg 1948, 5, pp.249-275 Wara W.M, Fellows C.F et al Radiation therapy for pineal tumors and suprasellar germinomas Radiology 1977, 124, pp.221-223 10 Bruce, Stein Neurosurgical Clinical 1990, 1, pp.123-127 11 Lupret V, Jeliai I Approach problems in anterior third ventricle tumors: Review of 33 Cases Surgery in and around the brain stem and the third ventricle (Springer Verlag, Berlin Heidelberg 1986 12 Jadik S, Wissing H, Fried Rich K et al,.Neurosurgery 2009, 64, p.533 153 ... present treatment results of 45 patients with pineal region lesions who were operated by infratentorial supracerebellar approach Methods * Study design: - A retrospective clinical evaluation of patients. .. patients with pineal region tumors was performed - A prospective study with surgical procedure: Microsurgery of pineal region tumors was performed by infratentorial supracerebellar approach Infratentorial. .. of pineal region tumors CT and MRI of the brain revealed information about tumor localization and extension CT-scans were obtained for 26 out of the 45 patients MRI scans were performed in 45 patients