Primary adrenal extranasal NK/T cell lymphoma with subcutaneous involvement demonstrated on FDG PET/CT: A clinical case report

Abstract

Rationale: Primary adrenal non-Hodgkin lymphomas are predominant diffuse large B cell lymphoma with frequently bilateral adrenal involvement, but the occurrence of nasal type extranodal NK/T cell lymphoma is relatively rare.

Patient concerns: A 40-year-old woman complaining of left back pain for 2-month was admitted to our department.

Diagnosis: Based on the feature of enhanced computed tomography (CT) images which showed huge bilateral well-defined adrenal masses with heterogeneous enhancement, she was tentatively diagnosed as having primary adrenal malignancy. Postoperative pathology revealed the diagnosis of primary adrenal Epstein-Barr virus-associated nasal type extranodal NK/T-cell lymphoma.

Interventions: Then, she underwent F-fluoro-2-deoxy-D-glucose (F-FDG) positron emission tomography (PET)/CT examination for staging, which showed homogeneously increased FDG uptake in the right adrenal gland and left thigh subcutaneous lesion, as well as heterogeneous increased FDG uptake in the left adrenal gland region with no abnormal uptake in the nasal cavity. Subsequently, the patient has performed 7 cycles of gemcitabine, L-asparaginase, ifosfamide, dexamethasone, etoposide (GLIDE) regimen and autologous stem cell transplantation.

Outcomes: Fortunately, the subsequent 2 follow-up FDG PET/CT scans within 1 year revealed complete resolution with no abnormal FDG uptake in the initially involved sites after 7 cycles of GLIDE chemotherapy and autologous stem cell transplantation.

Lessons: The enhanced CT and FDG PET/CT features of primary adrenal extranasal NK/T cell lymphoma are huge bilateral well-defined adrenal masses with heterogeneous enhancement, high FDG uptake, especially with subcutaneous involvement. And the awareness of this entity may help clinicians to differentiate it from other primary adrenal tumors and make reasonable therapeutic strategies. Besides, FDG PET/CT scan is very useful for the treatment follow-up of the primary adrenal extranasal NK/T cell lymphoma.

Figure 1

Abdominal enhanced CT (A and C: axial; B and D: sagittal) presented well-defined bilateral adrenal masses with the diameter of 75 cm (A and B, black arrows) and 31 cm (C and D, white arrows), showing heterogeneous enhancement, suggestive of primary adrenal malignancy. CT = computed tomography.

Figure 2

¹⁸F-PET/CT images showed homogeneously increased FDG uptake in the right adrenal gland (maximal SUVmax) of 15.7, A, H, I, and J: thick arrows) and left thigh subcutaneous lesion (SUVmax of 12.5, A, K, L, and M: arrows), as well as heterogeneous increased FDG uptake in the left adrenal gland region (SUVmax of 8.3, A, E, F, and G: thin arrows). The whole body PET/CT revealed no abnormal uptake of FDG in the nasal cavity (A, B, C, and D), indicating that the bilateral adrenal masses might be primary lesions with subcutaneous involvement. Fortunately, the subsequent 2 follow-ups FDG PET/CT scans revealed complete resolution with no abnormal FDG uptake in the initially involved sites after chemotherapy and autologous stem cell transplantation (N and O). CT = computed tomography, PET = positron emission tomography, SUVmax = standardized uptake value.