Delayed Diagnosis of T-Cell Prolymphocytic Leukemia: Approach to Chronic Lymphocytosis.

We present a case of lymphocytosis assumed and managed initially as a chronic lymphocytic leukemia. Shortly after initial visit, the patient's condition deteriorated rapidly with hepatosplenomegaly, pleural effusion, ascites, and skin lesions. Flow cytometry (FC) showed the presence of clonal T-cell population, reported as T-cell lymphoma. Due to rapid clinical deterioration, urgent therapy with cyclophosphamide, doxorubicin, vincristine, etoposide, prednisone was initiated, but with minimal response. This prompted further diagnostic testing and demonstrated tumor cells positivity for CD3, CD30, and TCL1 markers. The diagnosis was changed to T-cell prolymphocytic leukemia. The patient responded well to alemtuzumab (anti-CD52 monoclonal antibody) and reached complete remission. FC is an essential modality for assessing and screening circulating lymphocytes when a lymphoproliferative disorder (LPD) is suspected. There are several LPDs that present with different degrees of clonal lymphocytosis. Reactive lymphocytosis should be appropriately investigated. Indolent LPDs can be surveyed by the internist or family physician, while more aggressive LPDs typically require management by hematologists.

Activation of hippocampal microglia in a murine model of cancer-induced pain.

INTRODUCTION: Pain is a common and debilitating comorbidity of metastatic breast cancer. The hippocampus has been implicated in nociceptive processing, particularly relating to the subjective aspect of pain. Here, a syngeneic mouse model was used to characterize the effects of peripheral tumors on hippocampal microglial activation in relation to cancer-induced pain (CIP). MATERIALS AND METHODS: Mice were systemically treated with the colony-stimulating factor 1 receptor inhibitor Pexidartinib prior to intrafemoral (IF) or subcutaneous 4T1 carcinoma cell inoculation. Spontaneous and evoked nociceptive responses were quantitated throughout tumor development, and contralateral hippocampi were collected via endpoint microdissection for RNA analysis. Additionally, IF tumor-bearing animals were sacrificed on days 5, 10, 15, and 20 post 4T1 cell inoculation, and brain sections were immunofluorescently stained for Iba1, a marker of activated microglia. RESULTS: Ablation of these neuroimmune cells with the CSF1R inhibitor Pexidartinib delayed the onset and severity of cancer-induced nociceptive behaviors in IF tumor-bearing animals, adding to the body of literature that demonstrates microglial contribution to the development and maintenance of CIP. Furthermore, in untreated IF tumor-bearing mice, nociceptive behaviors appeared to progress in parallel with microglial activation in hippocampal regions. Immunofluorescent Iba1+ microglia increased in the dentate gyrus and cornu ammonis 1 hippocampal regions in IF tumor-bearing animals over time, which was confirmed at the mRNA level using relevant microglial markers. CONCLUSION: This is the first experimental evidence to demonstrate the effects of peripheral tumor-induced nociception on hippocampal microglial activation. The increase in hippocampal microglia observed in the present study may reflect the emotional and cognitive deficits reported by patients with CIP.