Primary CNS lymphoma with bilateral symmetric hypothalamic lesions presenting with panhypopituitarism and diabetes insipidus

Abstract

We present an unusual case of primary central nervous system (CNS) lymphoma presenting with bilateral symmetric hypothalamic lesions causing diabetes insipidus and hypopituitarism. A 50-year-old male presented initially with mental status changes, polyuria and polydipsia. The patient was determined to have diabetes insipidus (DI) and significant anterior pituitary deficiencies resulting in symptomatic pleural and pericardial effusions. Brain MRI with contrast demonstrated bilateral enhancement of his hypothalamus extending to the optic tract. The extensive diagnostic workup that ensued on his initial presentation was non-diagnostic as he had no obvious site of involvement that was easily accessible to biopsy. With close follow-up, the patient had rapid radiographic progression of his disease to his cerebral hemispheres. He therefore underwent brain biopsy and was diagnosed with primary CNS large B cell lymphoma. Chemotherapy has resulted in disease remission with resolution of MRI findings, but the patient has not had resolution of the hypopituitarism or DI. This case highlights the unique diagnostic challenge of patients with isolated hypothalamic lesions.

Figure 1

Figure 1A. Axial Flair MRI revealed enhancement in the hypothalamus and optic tract (see arrows). Figure 1B. Axial Flair MRI revealed extension of the enhancement in the right cerebral region (see arrows). Figure 1C. Axial Flair MRI revealed resolution of the enhancement in the hypothalamus and optic tract.

Figure 1

Figure 1A. Axial Flair MRI revealed enhancement in the hypothalamus and optic tract (see arrows). Figure 1B. Axial Flair MRI revealed extension of the enhancement in the right cerebral region (see arrows). Figure 1C. Axial Flair MRI revealed resolution of the enhancement in the hypothalamus and optic tract.

Figure 1

Figure 1A. Axial Flair MRI revealed enhancement in the hypothalamus and optic tract (see arrows). Figure 1B. Axial Flair MRI revealed extension of the enhancement in the right cerebral region (see arrows). Figure 1C. Axial Flair MRI revealed resolution of the enhancement in the hypothalamus and optic tract.

Figure 2

Figure 2A. Brain-biopsy specimen (20X). A hematoxylin and eosin stain showed a marked perivascular lymphocytic infiltrate, with penetration into and through vessel walls. Within the surrounding brain scattered atypical lymphocytes and reactive glial cells were present. Figure 2B. Brain-biopsy specimen (20X). Immunohistochemical staining performed using pan-B-cell marker CD20 revealed the immunophenotype of the tumor cells. Staining for CD3, a T-cell marker, (not shown) revealed a smaller population of reactive lymphocytes.

Figure 2

Figure 2A. Brain-biopsy specimen (20X). A hematoxylin and eosin stain showed a marked perivascular lymphocytic infiltrate, with penetration into and through vessel walls. Within the surrounding brain scattered atypical lymphocytes and reactive glial cells were present. Figure 2B. Brain-biopsy specimen (20X). Immunohistochemical staining performed using pan-B-cell marker CD20 revealed the immunophenotype of the tumor cells. Staining for CD3, a T-cell marker, (not shown) revealed a smaller population of reactive lymphocytes.