Primary leptomeningeal lymphoma: International Primary CNS Lymphoma Collaborative Group report

Cytomorphologic and Flow Cytometric Analysis of Cerebrospinal Fluid with T-Cell Lymphoma Involvement: A Retrospective Study of Rare Cases

OBJECTIVE

To compare the efficacy of conventional cytomorphologic analysis and flow cytometry (FC) in the diagnosis of T-cell lymphoma in the cerebrospinal fluid (CSF).

STUDY DESIGN

We performed a retrospective review of CSF samples from 2002 to 2012 that showed involvement of a T-cell lymphoma, either by cytomorphologic analysis and/or FC. Patients' demographics, clinical history and follow-up were assessed.

RESULTS

Thirty-nine CSF samples were identified from 9 patients. A definitive diagnosis of T-cell lymphoma involvement was made by cytomorphologic analysis and FC in 6 (15.4%) and 39 (100.0%) specimens, respectively. In specimens with definitive cytopathologic diagnoses, the cytomorphologic features included increased cellularity, a monotonous lymphoid population and large, atypical lymphoid cells. Considering cytomorphologic features only, 9 specimens demonstrated atypical lymphocytes not fulfilling the criteria for malignancy, and 24 specimens were negative for malignancy.

CONCLUSIONS

CSF with T-cell lymphoma involvement may yield paucicellular or acellular specimens depending on the volume of the CSF, the time interval between specimen collection and specimen processing and the application of preservative to CSF. The rate of detection of T-cell lymphoma in the CSF by FC is unequivocally higher than by cytomorphologic analysis. Careful attention to clinical history is crucial, as FC testing may be tailored to evaluate for T-cell lymphoproliferative disorders in limited samples.

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.

Primary CNS lymphoma

Primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system is an aggressive malignancy that exhibits unique biological features and characteristic clinical behaviour, with overall long-term survival rates of around 20–40 %. Clinical outcome has improved following the advent of chemoradiation protocols incorporating high-dose methotrexate in the mid-1980s, but disease relapse and adverse neurocognitive sequelae remain major clinical challenges. To address this, investigators have focused on improving drug therapy with novel cytotoxic combinations, monoclonal antibody therapy, and intensive chemotherapy consolidation approaches, in an attempt to improve disease control whilst reducing the requirement for whole-brain radiotherapy. Outcomes for patients that are older, immunocompromised, or have relapsed/refractory disease remain unsatisfactory and there is a paucity of clinical trial data to guide treatment of these groups. This review highlights recent advances in pathobiology, imaging, and clinical management of PCNSL and looks ahead to research priorities for this rare and challenging lymphoid malignancy.

Primary T cell central nervous system lymphoblastic lymphoma in a child: case report and literature review

PURPOSE

Primary central nervous system lymphoma (PCNSL) of T cell origin is rare in pediatric patients. We report a case of T cell PCNSL in a 12-year-old boy and review the literature to highlight the importance of brain biopsy to definitively establish the diagnosis when PCNSL is suspected.

CASE REPORT

A 12-year-old boy presented with worsening left-sided weakness, nausea, vomiting, headache, blurred vision, and diplopia. Magnetic resonance imaging revealed right parietal gyral thickening with faint meningeal contrast enhancement. No clear diagnosis was identified after serum testing, cerebrospinal fluid analysis, and cerebral angiography. To establish the diagnosis definitively, a right craniotomy and open, frameless stereotactic biopsy were performed, which yielded the diagnosis of lymphoblastic T cell lymphoma.

CONCLUSIONS

PCNSL of T cell origin in children remains poorly studied, with only 18 detailed cases reported over the last three decades, including this case. Establishing a definitive diagnosis of PCNSL is challenging, and a brain biopsy is often required to obtain enough tissue for pathological analysis. Increasing awareness and identification of children diagnosed with T cell PCNSL is needed to better understand the molecular biology of this disease and develop more standardized treatment regimens.