Pineal region tumors

Gliomas of the pineal region

Although several series of pineal region tumors are available, the issue of pineal gliomas has been scarcely faced in the literature. Gliomas are usually included in largest series of pineal neoplasms. Therefore, whether pineal gliomas share the biological behavior of either hemispheric gliomas or other midline lesions is not yet defined. The aim of this retrospective study is to analyze long-term morbidity and mortality of these lesions. In English published literature gliomas account for about 14-22 % of all pineal region tumors. Most of these tumors are pilocytic astrocytomas, while glioblastoma multiforme is rare. We retrospectively analyzed all pineal region tumors operated on in our department in the last 28 years, and identified eight pineal astrocytomas, accounting for 14.03 % of all pineal tumors. The series includes four pilocytic astrocytomas, two grade II diffuse astrocytomas, and two anaplastic astrocytomas. A comprehensive review of the available literature data shows that the mean survival time of WHO grade II gliomas is shorter when tumor grows in the pineal region than for hemispheric locations, although the limited amount of available data prevents a rigorous statistical analysis. This difference might be due to the peculiar infiltrating behavior of pineal tumors, which often can't be satisfactorily resected from vital structures.

Pineal region tumor manifesting initially as hearing impairment

An 18-year-old male presented with a pineal region germinoma with hearing impairment as the chief complaint. Magnetic resonance image demonstrated a well-enhanced multi-cystic tumor extending into the upper fourth ventricle and wall of the bilateral lateral ventricles. Audiometry revealed bilateral mild hearing impairment in the low frequencies. Auditory brainstem response recording showed low amplitudes in all waves (IV-V/I ratio < 1) with prolong latencies (I-V and III-V) on the right but no discernable wave at 60 dB clicks on left. Hearing impairment and audiometric findings were improved after ventriculoperitoneal shunt operation. The hearing impairment appeared to be a mixed (conductive and sensorineural) type. The tumor was responsible for the sensorineural deafness because of invasion and compression of the central auditory structures. The inferior brachium was maximally compressed anterolaterally by the dilated bilateral lateral ventricles and posteromedially by the tumor. Hydrocephalus caused conductive deafness by halting or arresting the footplate of stapes movement, as a consequence of high-pressure transmission through the cochlear aqueduct.

Radiation therapy of pineal region tumors: 25 new cases and a review of 208 previously reported cases

PURPOSE

Malignant pineal region tumors are rare neoplasms arising in midline structures of the brain. This report analyzes the influence of histology, tumor location, radiation dose, treatment volume, age and cerebrospinal fluid findings on freedom from relapse, freedom from spinal relapse and survival.

METHODS AND MATERIALS

Patient and treatment parameters of 25 cases of pineal region tumors managed at Stanford University are presented, and an additional 208 published cases were reviewed. Univariate and multivariate analysis were performed to delineate parameters predictive of freedom from relapse, freedom from spinal relapse, and survival for all 233 patients.

RESULTS

The 5- and 10-year freedom from relapse for Stanford patients was 63% and 46%, respectively. The 5- and 10-year survival for Stanford patients was 67% and 61%, respectively. The 5- and 10-year freedom from relapse for the total 233 cases was 66% and 61%, respectively. The 5- and 10-year survival for all patients was 74% and 68%, respectively. For the entire group, biopsy confirmed germinoma and non-biopsied tumors had superior freedom from relapse compared to non-germinoma germ cell tumors (p = 0.03, p = 0.005, respectively). Non-biopsied patients had improved survival compared to non-germinoma germ cell tumors (p = 0.004). Pineal parenchymal tumors had worse freedom from relapse compared to non-biopsied patients (p = 0.04). For patients with suprasellar tumors, germinomas were associated with improved freedom from relapse compared to non-germinoma germ cell tumors (p = 0.02). Simultaneous pineal and suprasellar tumors had superior survival compared to solitary tumors of pineal (p = 0.04), suprasellar (p = 0.03), or third ventricle location (p = 0.03). Twenty-two patients (9.4%) developed isolated spinal relapse. Five- and 10-year spinal relapse rates for all patients were 11% and 13%. Survival after spinal relapse was 19%. Pineal parenchymal tumors had lower freedom from spinal relapse compared to non-biopsied patients (p = 0.001). For tumors located in the pineal gland, germinomas and pineal parenchymal tumors had lower freedom from spinal relapse than did non-biopsied patients (p = 0.006, p = 0.004, respectively). Pineal germinomas had lower freedom from spinal relapse than germinomas with suprasellar location (p = 0.04). Univariate and multivariate analysis identified tumor histology as the most significant predictor of freedom from relapse, freedom from spinal relapse and survival.

CONCLUSION

Histologic type had the greatest impact on outcome. Treatment recommendations should be based on assessment of histologic type and extent of disease.

Hearing impairment resulting from a pineal region meningioma

Because of extensive interconnections within the auditory pathways, hearing impairment from a central origin is rare. We describe a patient with a large pineal region meningioma in whom hearing loss was the predominant symptom. The patient promptly recovered hearing after the surgical removal of the tumor. The mechanism of this phenomenon is discussed.

Gadolinium-enhanced MR imaging in the management of a midline cerebral dysgerminoma

Magnetic Resonance (MR) imaging has proved to be an excellent modality for the evaluation of CNS tumors and detection of metastatic seeding through CNS pathways. We present a case of cerebral dysgerminoma in which the use of gadopentetate dimeglumine (Gd-DTPA) enhancement added important information in lesion detection and delineation for treatment planning. Our results, and a review of recent literature, suggest that Gd-DTPA-enhanced MR imaging may be useful for initial and follow-up evaluation of CNS dysgerminomas.