Primary cardiac cytotoxic T-cell lymphoma presenting with neurological deficits: a case report.
BACKGROUND
Primary cardiac lymphoma is extremely rare in immunocompetent patients. Clinical manifestations vary, and, most often, diagnosis is not made until autopsy. The majority of reported primary cardiac lymphoma cases have been of B-cell origin, while T-cell cardiac lymphomas have been extremely rare. Occasionally, lymphomas and other systemic malignancies clinically present as paraneoplastic neurological syndromes.


METHODS
We report a unique case of primary cardiac peripheral T-cell lymphoma of cytotoxic phenotype, clinically presenting with neurological features of external ophthalmoplegia and lower cranial nerve paresis mimicking mitochondrial cytopathy, that was recognized at autopsy. Brain and thoracoabdominal viscera retrieved at autopsy were fixed in 10% buffered formalin and processed for paraffin embedding. In addition to routine histology, immunohistochemistry for immunophenotypic characterization of lymphoma cells was performed. Fresh skeletal muscle was processed for cryosectioning and histochemical staining.


RESULTS
On gross examination, the heart showed multiple circumscribed, whitish nodules on both sides. Histological examination of these nodules revealed lymphomatous deposits-cells expressing CD45, CD2, CD3, CD5, CD7, CD8, perforin, and granzyme B. Histological sections from the brain showed foci of demyelination and patchy perivascular lymphoid cell aggregates in leptomeninges and within the parenchyma. These lymphoid cells expressed CD2, CD3, and CD5, with the T cells being predominantly CD4 (CD4:CD8>2), which was unlike the CD8-predominant lymphomatous infiltrate in the heart. Hence, these lymphoid cells in the brain, rather than disseminated lymphoma cells, were considered to be related to the demyelinating process. There was no evidence of lymphomatous deposits in the rest of the viscera examined.


CONCLUSION
A diagnosis of primary cardiac peripheral T-cell lymphoma of cytotoxic phenotype clinically manifesting as paraneoplastic demyelinating lesions in the brain was described.