Primary Meningeal T-Cell Lymphoma at the Clivus Mimicking a Meningioma

Imaging features of primary dural lymphoma: A report of 3 cases

Primary dural lymphoma (PDL) constitutes a rare subgroup within central nervous system lymphomas, defined by its exclusive confinement to the dura mater, without a concurrent brain or systemic lymphatic involvement. This distinctive localization presents diagnostic challenges. In this report, we present a series of 3 cases where initial radiological presentations resembled meningiomas. We meticulously analyze key differentiating imaging characteristics, in CT, morphological MRI, and spectroscopy imaging. And show that recognizing and understanding these nuanced features are pivotal in enabling accurate differentiation of PDL and facilitating timely clinical intervention.

Primary Dural Lymphoma: Clinical Cases and Literature Review

Primary dural lymphoma (PDL) is an extranodal non-Hodgkin lymphoma that accounts for less than 1% of all central nervous system lymphomas. Primary dural lymphoma grows from the dura mater, and it is often diagnosed as meningioma or acute subdural hematoma due to its radiological characteristics. Surgery is the gold standard of therapy; in many patients, PDL is relatively benign with good outcome. Authors report their experience in three patients affected by extranodal non-Hodgkin lymphoma (PDL) mimicking a meningioma.

Primary Lymphoma of the Skull Base in the Chinese: Clinical, Radiological, Pathological, and Therapeutic Experience in a Series of 8 Patients

BACKGROUND

Primary lymphoma of the skull base (PLSB) is an extremely rare neoplasm and not much is known regarding the clinical features of, treatment strategies for, and prognoses of these lesions. We investigated the manifestations and clinical outcomes of Chinese patients with PLSB.

METHODS

We retrospectively reviewed the data from 8 consecutive patients with PLSB who had been treated at our center from October 2008 to December 2016 and analyzed their clinical features, treatment strategies, and prognoses.

RESULTS

Of the 8 patients, 3 were men and 5 were women, with a male/female ratio of 0.6. The median age was 53.5 years. In most instances, the onset was characterized by headache, followed by dysfunction of the cranial nerves. The most frequently affected region was the cavernous sinus. On magnetic resonance imaging, the main characteristic was that the internal carotid artery was encased by the tumor without an obvious tendency to be deformed, dislocated, or narrowed. All patients underwent surgical biopsy via a transsphenoidal or sublabial-transmaxillary approach. The pathological diagnosis was non-Hodgkin lymphoma for all 8 patients, with diffuse large B-cell lymphoma in 7 patients. The patients underwent chemotherapy and involved-field radiotherapy. The median overall survival was 52 months, and the 1-year progression-free survival rate was 87.5%.

CONCLUSIONS

PLSB is a rare disease and a diagnostic challenge, with most cases in the Chinese due to diffuse large B-cell lymphoma. We found that the incidence peaked in middle and old age, and the cavernous sinus was usually affected. Multidisciplinary treatment involving surgical biopsy, chemotherapy, and radiotherapy was an effective therapeutic strategy.

Isolated hypoglossal nerve palsy as a presenting symptom of metastatic peripheral T-cell lymphoma - not otherwise specified (PTCL-NOS): a unique case & a review of the literature

Extensive and significant technological advancements have enhanced the sensitivity and accuracy of the pathologic classification, diagnosis, and therapeutics of lymphoma. These advances have prompted a more comprehensive understanding of neoplastic behavior and have led to improvements in both treatment and prognosis. This paper presents a comprehensive review of lymphoma and features a case report of a unique presentation of peripheral T-cell lymphoma - not otherwise specified that presented with isolated hypoglossal nerve dysfunction.

The identification of H3F3A mutation in giant cell tumour of the clivus and the histological diagnostic algorithm of other clival lesions permit the differential diagnosis in this location

BACKGROUND

Giant Cell Tumour of Bone (GCT) is a locally aggressive primary bone tumour that usually occurs at the epiphyses of the long bones of the appendicular skeleton with a tendency to recurrence. Recurrent somatic H3F3A mutations have been described in 92% of GCT cases. GCTs involving the Clivus are extremely rare lesions and less than 15 cases are described in the literature. They represent a surgery challenge and are easily misdiagnosed. Our aim was to reveal if the genetic bases underlying Clival GCTs were the same of GCTs of long bones to improve the diagnosis and treatment.

METHODS

The targeted somatic sequencing of GCT-related genes (H3F3A, H3F3B, IDH1, IDH2 and ZNF687) was performed on Clival GCT biopsies of two different cases. Histological analyses on the same tissues were used to detect the neoplastic population and its expression profile.

RESULTS

Sanger sequencing revealed that both patients were positive for the p.Gly34Trp mutation in the H3F3A gene. Immunofluorescence assay using monoclonal antibody, specifically detecting the mutant H3.3, highlighted that the mutation only involved the mononuclear cell population and not the multinucleated giant cells. Moreover, immunohistochemistry assay showed that RANKL was highly expressed by the stromal cells within Clival GCT, mimicking what happens in GCT of the long bones. In addition, systematic literature review allowed us to generate a histology-based diagnostic algorithm of the most common clival lesions.

CONCLUSIONS

We conclude that the Clival GCT is genetically defined by somatic mutation in the H3F3A gene, linking it to the GCT of long bones. The similarity with GCTs of long bones let us to hypothesize the utility of Denosumab therapy (already effective for GCTs) in these surgically challenging cases. Moreover, H3F3A genetic screening can be combined to the histological analysis to differentiate GCTs from morphologically similar giant cell-rich sarcomas, while the histological diagnostic algorithm could help the differential diagnosis of other clival lesions.

Endoscopic Resection of Clival Malignancies

Surgical management of clival lesions presents numerous therapeutic challenges because of the close proximity of surrounding critical structures. With a detailed understanding of the endoscopic endonasal approach and relevant considerations, appropriate lesions can be removed in a safe and minimally invasive manner. Use of this technique as a primary approach represents the standard of care for many lesions at leading skull base centers, although adjunct techniques may be necessary in extensive lesions and those with significant lateral extension.

Neuropathies associated with lymphoma†

Neuropathy occurs with various manifestations as a consequence of lymphoma, and an understanding of the etiology is necessary for proper treatment. Advances in medical imaging have improved the detection of peripheral nerve involvement in lymphoma, yet tissue diagnosis is often equally important. The neoplastic involvement of the peripheral nervous system (PNS) in lymphoma can occur within the cerebrospinal fluid (CSF), inside the dura, or outside of the CSF space, affecting nerve root plexuses and peripheral nerves. The infiltration of either cranial or peripheral nerves in lymphoma is termed neurolymphomatosis (NL). These infiltrations can occur as mononeuropathy, multifocal neuropathy, symmetric neuropathies, or plexopathies. In rare cases, intravascular lymphoma (IL) can affect the PNS and an even rarer condition is the combination of NL and IL. Immune-mediated and paraneoplastic neuropathies are important considerations when treating patients with lymphoma. Demyelinating neuropathies, such as Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy, occur more frequently in non-Hodgkin's lymphoma than in Hodgkin's disease. Paraproteinemic neuropathies can be associated with lymphoma and paraneoplastic neuropathies are rare. While the treatment of lymphomas has improved, a knowledge of neurotoxic, radiotherapy, neoplastic, immune-mediated and paraneoplastic effects are important for patient care.

Incidental meningiomas

With the increasing availability and use of modern brain diagnostic imaging modalities, discovery of incidental meningiomas has become fairly common. This creates a dilemma among neurosurgeons as to whether these lesions should be treated. Numerous natural history studies have been published in an effort to shed light on the potential for growth of incidental meningiomas. The available data appear to suggest that these tumors can fall into 1 of 3 main growth patterns: no growth, linear growth, or exponential growth. The therapeutic strategy selected should also consider several other factors, mainly the risk of complications from an eventual surgery, the possibility of malignancies and other pathological conditions that mimic meningiomas, and the age and medical condition of the patient. The authors believe that most asymptomatic incidental meningiomas can be observed using serial imaging and clinical follow-up evaluations. Surgical interventions are typically reserved for large, symptomatic lesions and those with documented potential for significant growth.