Tumores germinales intracraneales: revisión de 21 años

Clinicopathological spectrum of central nervous system germ cell tumors: A single-institution retrospective study

CONTEXT

Central nervous system germ cell tumors (CNSGCTs) though rare is the second most common extragonadal site for GCTs.

AIMS

To determine the clinicopathological features of CNSGCTs diagnosed at our center.

SETTINGS AND DESIGN

A retrospective study of all histologically diagnosed CNSGCTs, during 2006-2019.

MATERIALS AND METHODS

The patients' data were retrieved from the hospital information systems and analyzed.

STATISTICAL ANALYSIS

Data on categorical variables were analyzed as percentages, and data on continuous variables calculated as mean. Chi-square test or Fisher's exact test was used to study association between variables.

RESULTS

Of the total 34 cases with CNSGCT, age ranged from 1 to 27 years, majority in the second decade (19/34; 56%). Male: female (M: F) ratio was 1.6:1. Single site involvement was seen in 27 cases (27/34; 79%), whereas seven (7/34; 21%) showed bi/multifocal involvement. Among the unifocal cases, common sites involved were suprasellar (12/27; 44.4%), closely followed by the pineal (10/27; 37%). All multifocal tumors affected suprasellar compartment, being bifocal with pineal in four cases. A male gender predilection was noted among pineal region (9/10;90%) and multifocal tumors (5/7;71%). Germinoma was the commonest subtype (21/34; 61.8%) with male gender predilection (17/21; 81%) (M: F =4.3:1), with female predilection seen among mixed GCTs (MGCTs) (8/10; 80%) (M: F =1:4) and suprasellar location (M: F =1:2). Serum tumor markers (25 cases) and CSF markers (7 cases) were concordant with histology in all, except two cases.

CONCLUSION

Though histology and immunohistochemistry were diagnostic, correlation between serum and/or CSF marker was essential to rule out GCT component(s) that may be missed on biopsy due to sampling error.

Contribution of whole slide imaging-based deep learning in the assessment of intraoperative and postoperative sections in neuropathology

The pathological diagnosis of intracranial germinoma (IG), oligodendroglioma, and low-grade astrocytoma on intraoperative frozen section (IFS) and hematoxylin-eosin (HE)-staining section directly determines patients' treatment options, but it is a difficult task for pathologists. We aimed to investigate whether whole-slide imaging (WSI)-based deep learning can contribute new precision to the diagnosis of IG, oligodendroglioma, and low-grade astrocytoma. Two types of WSIs (500 IFSs and 832 HE-staining sections) were collected from 379 patients at multiple medical centers. Patients at Center 1 were split into the training, testing, and internal validation sets (3:1:1), while the other centers were the external validation sets. First, we subdivided WSIs into small tiles and selected tissue tiles using a tissue tile selection model. Then a tile-level classification model was established, and the majority voting method was used to determine the final diagnoses. Color jitter was applied to the tiles so that the deep learning (DL) models could adapt to the variations in the staining. Last, we investigated the effectiveness of model assistance. The internal validation accuracies of the IFS and HE models were 93.9% and 95.3%, respectively. The external validation accuracies of the IFS and HE models were 82.0% and 76.9%, respectively. Furthermore, the IFS and HE models can predict Ki-67 positive cell areas with R² of 0.81 and 0.86, respectively. With model assistance, the IFS and HE diagnosis accuracy of pathologists improved from 54.6%-69.7% and 53.5%-83.7% to 87.9%-93.9% and 86.0%-90.7%, respectively. Both the IFS model and the HE model can differentiate the three tumors, predict the expression of Ki-67, and improve the diagnostic accuracy of pathologists. The use of our model can assist clinicians in providing patients with optimal and timely treatment options.

Radiological Latency in Pineal Germinoma: A Case Report and Literature Review

Suprasellar germinomas can present with non-diagnostic, or even normal results on imaging. The spectrum of reported cases ranges from normal imaging, thickened pituitary stalks, to discrete tumour growths. This similar phenomenon is less commonly seen in the pineal region, or bifocal germinomas, and the literature is sparse with only a few case series or reports mentioning a similar presentation of signs and symptoms preceding radiological evidence of diagnosis. We report a case of pineal germinoma presenting with dorsal midbrain syndrome with no evidence of tumour growth on initial imaging despite symptoms. For patients presenting with this clinical radiological latent period, follow-up imaging is useful to identify interval development of germinomas. This applies to patients with dorsal midbrain syndrome, or even other unexplained ophthalmoplegia, as the initial sign of pineal region germinoma, despite normal imaging.

Pineal germinoma in a young adult: A case report

BACKGROUND

Intracranial germinomas (GN) are rare cancers that primarily affect children, making them rarer still in adults. Standard treatment for this neoplasm includes neoadjuvant chemotherapy (NC) followed by radiotherapy (RT) or RT at a higher dose and larger field. These recommendations are based on studies focused mostly on children; it is currently unclear whether this treatment is applicable to adults.

CASE

We present a case of a 23-year-old adult male with no underlying pathologies, drug allergies, or family history of cancer, who presented for medical evaluation with blurred vision, diplopia, forgetfulness, and weight loss starting 3-4 months before the evaluation. Clinical examination indicated Parinaud's Syndrome. Magnetic resonance imaging (MRI) and computed tomography (CT) revealed a pineal tumor with ependymal dissemination in both lateral ventricles, which was causing obstructive hydrocephalus. The patient had surgery consisting of ventriculostomy, Holter shunt insertion, cisternal ventricular intubation, and cisterna magna anastomosis to improve ventricular drainage. Pathology confirmed pineal germinoma. Cerebrospinal fluid cytology and MRI of the axis were negative. Four cycles of NC were given to the patient (carboplatin, etoposide, and ifosfamide), with reduced dosage. Once a partial volumetric response was confirmed, whole-ventricular radiotherapy (WVR) was initiated with a total tumor bed dose of 45 Gy over 25 sessions in 5 weeks. Optimum clinical results were observed, and no short-term (<90 day) radiation toxicity was observed. The patient was able to resume his normal activities soon after treatment. Follow-ups over 2 years post-surgery indicated continued control of the lesion and absence of symptoms except for mild diplopia.

CONCLUSION

Although this is a case report, these data suggest that a reduced NC course and WVR may effectively treat adult GN. This protocol likely decreases the risk of undesirable NC and RT secondary effects, while providing excellent local control; however, using a narrower RT field is not recommended.

Management trends and outcomes of pineal germinoma in a multi-institutional Australian cohort

Pineal germinoma is rare with high cure rates following craniospinal radiotherapy. Efforts to reduce the radiotherapy dose and field via combination with chemotherapy suggest comparable disease control and reduced neurocognitive impairments, while the efficacy of immunotherapy in pineal germinoma remains undetermined. This report aimed to review clinical outcomes in patients treated for pineal germinoma in Queensland, Australia, and assess for Programmed Death-Ligand1 (PD-L1) expression. Patients who commenced radiation and/or chemotherapy for pineal germinoma from 2005 to 2017 were retrospectively identified using Queensland Oncology Online database. Demographic, diagnostic, treatment, and outcome data was obtained from electronic medical records. PD-L1 immuno-histochemistry was performed on available specimens. Eighteen patients with long-term follow-up data were identified. Median age at diagnosis was 16.8 years (range 9-46 years). Diagnosis was made histologically in fifteen patients, and radiologically in three. All patients underwent radiotherapy (median 36 Gy (range 21-54 Gy)) with lower median dose delivered with whole ventricle irradiation (12/18patients) than craniospinal irradiation (5/18patients). Sixteen patients received chemotherapy preceding radiotherapy. All patients are alive at median 7.25 years from primary treatment completion (range 2.03-13.1 years). Relapse occurred in three patients (16.67%) following treatment response, all of whom achieved remission following high-dose chemotherapy with stem-cell support and craniospinal radiotherapy. Post-treatment functional outcomes were similarly excellent. PD-L1 expression was low (1-49% cells) or negative in 87% of tumours tested but results were confounded by specimen quality and availability. Reduced-dose radiotherapy with chemotherapy does not compromise outcome and is standard of care at this institution. Immunotherapy is unlikely to become standard treatment in the near future.

Comparison on epidemiology, tumor location, histology, and prognosis of intracranial germ cell tumors between Mayo Clinic and Japanese consortium cohorts

OBJECTIVE

Central nervous system (CNS) germ cell tumors (GCTs) are rare malignant neoplasms that arise predominantly in adolescents and young adults. CNS GCTs demonstrate characteristic trends in national associations, with implications for both tumor incidence and genetics. Although the incidence of CNS GCTs is markedly higher in East Asia than Western countries, direct comparative analyses between these CNS GCT populations are limited.

METHODS

In Japan, to facilitate the genomic analyses of CNS GCTs, the Intracranial Germ Cell Tumor Genome Analysis Consortium was established in 2011, and more than 200 cases of GCTs are available for both tumor tissue and clinical data, which is organized by the National Cancer Center (NCC) Japan. At the Mayo Clinic, there have been 98 cases of intracranial GCTs treated by the Department of Neurologic Surgery since 1988. In this paper, the authors compared the epidemiology, clinical presentation including location and histology, and prognosis between cases treated in the US and Japan.

RESULTS

There was no significant difference in age and sex distributions between the databases. However, there was a significant difference in the tumor locations; specifically, the frequency of basal ganglia was higher in the NCC database compared with the Mayo Clinic (8.4% vs 0%, p = 0.008), and bifocal location (neurohypophysis and pineal gland) was higher at the Mayo Clinic than at the NCC (18.8% vs 5.8%, p = 0.002). There was no difference in histological subdivisions between the databases. There was no difference in progression-free survival (PFS) and overall survival (OS) of germinoma cases and OS of nongerminomatous GCT (NGGCT) cases treated with chemotherapy and radiation therapy covering whole ventricles. However, PFS of NGGCTs differed significantly, and was better in the NCC cohorts (p = 0.04).

CONCLUSIONS

There appears to be a differential distribution of GCTs by neuroanatomical location between major geographic and national groups. Further study is warranted to better characterize any underlying genomic, epigenetic, or environmental factors that may be driving the phenotypic differences.