Adjacent epidermoid cyst and primary central nervous system lymphoma: case report

BACKGROUND: Except for cases with radiotherapy or phacomatosis, multiple primary brain tumors of different histologic types are rare. The authors report the association of an epidermoid cyst and a primary CNS lymphoma. CASE DESCRIPTION: A 66-year-old man with a 20-year history of gait disturbance was admitted because of recently worsening symptoms. Magnetic resonance imaging showed an abnormal mass in the posterior fossa. The mass lesion had the appearance of a cystic tumor with a large mural nodule. Gross total removal of the tumor was performed. Histologic examination disclosed the cystic portion to be an epidermoid, whereas the nodular portion exhibited the histologic and immunohistochemical features of a malignant lymphoma. The lymphoma cells were shown to harbor EBV by in situ hybridization. CONCLUSIONS: To our knowledge, this is the first report of the coexistence of an epidermoid cyst and primary CNS lymphoma. When the lesions are adjacent, a definite preoperative diagnosis can be difficult. Epstein-Barr virus-associated CNS lymphoma is rare among the immunologically normal population. The possible pathogenesis for the coexistence of these 2 tumors is discussed.     

Incidence and outcomes of primary central nervous system lymphoma in solid organ transplant recipients

Primary central nervous system lymphoma (PCNSL) risk is greatly increased in immunosuppressed human immunodeficiency virus–infected people. Using data from the US transplant registry linked with 17 cancer registries (1987‐2014), we studied PCNSL and systemic non‐Hodgkin lymphoma (NHL) in 288 029 solid organ transplant recipients. Transplant recipients had elevated incidence for PCNSL compared with the general population (standardized incidence ratio = 65.1; N = 168), and this elevation was stronger than for systemic NHL (standardized incidence ratio=11.5; N = 2043). Compared to kidney recipients, PCNSL incidence was lower in liver recipients (adjusted incidence rate ratio [aIRR] = 0.52), similar in heart and/or lung recipients, and higher in other/multiple organ recipients (aIRR = 2.45). PCNSL incidence was higher in Asians/Pacific Islanders than non‐Hispanic whites (aIRR = 2.09); after induction immunosuppression with alemtuzumab (aIRR = 3.12), monoclonal antibodies (aIRR = 1.83), or polyclonal antibodies (aIRR = 2.03); in recipients who were Epstein‐Barr virus–seronegative at the time of transplant and at risk of primary infection (aIRR = 1.95); and within the first 1.5 years after transplant. Compared to other recipients, those with PCNSL had increased risk of death (adjusted hazard ratio [aHR] = 11.79) or graft failure/retransplantation (aHR = 3.24). Recipients with PCNSL also had higher mortality than those with systemic NHL (aHR = 1.48). In conclusion, PCNSL risk is highly elevated among transplant recipients, and it carries a poor prognosis.     

Epstein–Barr virus‐positive post‐transplant lymphoproliferative disorder of the central nervous system,after renal transplantation with a discrepancy in viral load between peripheral blood and cerebrospinal fluid

A 43‐year‐old female developed an Epstein–Barr virus (EBV)‐positive post‐transplant lymphoproliferative disorder (PTLD) in the central nervous system (CNS), 14 years after renal transplantation. One year prior to presentation, the patients’ treatment regimen was altered from cyclosporine, azathioprine, and prednisone to mycophenolate mofetil and prednisone. Magnetic resonance imaging of the brain revealed lesions suspect for malignant lymphoma. The EBV real‐time polymerase chain reaction (PCR) on peripheral blood was negative, but highly positive on cerebrospinal fluid. EBV‐positive PTLD was confirmed using histological analysis of cerebral biopsies. Despite tapering of immune suppressive medication and treatment with rituximab and chemotherapy, the patient deceased 50 days after presentation. This case illustrates that vigilance is required when presented with a negative EBV PCR result on peripheral blood when PTLD of the CNS is suspected. This late presentation suggests a relation to the switch in immunosuppressive regimen 1 year earlier.