To the Editor: We report the serendipitous finding of non-Hodgkin’s lymphoma in a patient with adrenal Cushing’s syndrome.

A 62-year-old previously well man (body mass index, 22 kg/m2) was referred to our institution with newly diagnosed type 2 diabetes, hypertension and dyslipidaemia. Clinical findings included oral thrush, bilateral severe pitting lower limb oedema, lower limb proximal myopathy, kyphosis, and increased abdominal girth (waist circumference, 92 cm), raising suspicion of Cushing’s syndrome (Box 1).

Biochemical assessment revealed normal electrolytes, an unsuppressed early morning cortisol (following 1 mg dexamethasone), urinary free cortisol 6475 nmol/day (reference range, 0 – 250 nmol/day), and undetectable adrenocorticotropic hormone levels. Twenty-four-hour urinary catecholamine was normal. His testosterone level was 3.2 nmol/L, and dehydroepiandrosterone sulfate level was normal.

Abdominal computed tomography showed a right adrenal mass that measured 3.1 × 2.8 × 3.4 cm (density, 36 Hounsfield units). Thoracic spine x-rays revealed wedge compression fractures at T-10 and T-11. Bone densitometry showed T-scores of − 3.3 at L2 – 4 and − 2.3 at the right femoral neck. Total body fat (18.5 kg; 33%) was higher than the recommended range for age and sex (13%–25%).

The patient had a laparoscopic right adrenalectomy. Surgical excision was complete. Post-operatively, blood glucose and blood pressure returned to normal. Histopathology revealed an adrenal cortical tumour with atypical features, including a preponderance of eosinophilic cells, small numbers of clear cells, prominent nuclear pleomorphism, large nucleoli and occasional mitoses (Box 2A). However, the proliferation fraction (Ki67) was low and there was no necrosis. There was no large vessel invasion, although a single area of small vessel invasion was present (Box 2B).

Unexpectedly, the adipose tissue adjacent to the adrenal gland was infiltrated by a diffuse large B-cell non-Hodgkin’s lymphoma (Box 2B). This was confirmed by positive CD20 immunohistochemistry. Bone marrow biopsy was normal. [18F]Fluorodeoxyglucose positron emission tomography (FDG-PET) scan showed increased uptake in the right adrenal bed only. The patient was treated with six courses of CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine and prednisolone) in combination with rituximab. A repeat FDG-PET scan 1 month after chemotherapy was clear.

We speculate that lymphoma progression was suppressed by the coexistent steroid-producing adrenal tumour. The decision to treat the non-Hodgkin’s lymphoma was, in part, based on reports of progression of haematological disease following treatment of Cushing’s syndrome.1,2 Although histopathological examination of the tumour revealed some features suggestive of adrenocortical carcinoma, the distinction between adenoma and carcinoma can be difficult. In patients with recurrent or metastatic adrenocortical carcinoma, partial response has been reported using a combination of cylophosphamide, vincristine, cisplatin and teniposide.3 Two of these agents were used to treat our patient’s lymphoma.