Primary central nervous system lymphoma

• This comprises 1% of lymphomas and 1-2% of brain tumors, though the incidence is rising with no known cause.

• It is important to identify these in time, as a high number of primary DLBCL tumors can be cured using the currently available treatments.

• The average age of patients with this type of tumor is 60.

• Clinical manifestations:
  • Neurological deficit (over half of patients)
  • Behavioral changes
  • Symptoms of intracranial hypertension or disorders of the eye

• Tumor lesions are located in the brain (in two-thirds of cases), while in the rest this affects the cerebellum, eyeball, spinal cord, or cerebrospinal fluid.
• Treatment: The treatment of choice is chemotherapy (administration of drugs that pass the blood-brain barrier). The approaches used include high doses of methotrexate and cytarabine.

Primary cutaneous DLBCL

• This lymphoma owes its name to the fact that it primarily affects the legs, although 10-15% of cases affect the trunk, head, and arms.

• It represents 20% of cutaneous B-cell lymphomas and develops especially in women over age 70.

T-cell/histiocyte-rich B-cell lymphoma

• Biopsies of these tumors are noteworthy due to the fact that the infiltrate has a high presence of T-lymphocytes and histiocytes together with B-cells.
• This subtype comprises 5% of DLBCL cases and is normally found in middle-aged men.
• The presenting symptoms include fever, malaise, and lymph-node involvement to varying degrees, affecting the spleen, liver, and bone marrow.