Adrenal masses of varied etiology: anatomical and molecular imaging features on PET-CT

Superiority of 18 F-FDG PET/CT to 68 GA-FAPI PET/CT in Adrenocortical Tumor Imaging

ABSTRACT

18 F-FDG PET/CT was performed to evaluate the response to treatment in a 62-year-old female patient who was operated for adrenocortical carcinoma. High FDG uptake was observed in recurrent lesion in the left adrenal gland site and metastatic lesions. In the 68 Ga-FAPI-04 PET/CT study, low FAPI uptake was observed in both recurrences and metastases. In this case, we demonstrated the superiority of 18 F-FDG PET/CT over 68 Ga-FAPI-04 PET/CT in the evaluation of adrenocortical carcinoma.

68Ga-DOTANOC PET/CT in Multiple Endocrine Neoplasia 1 With Associated Adrenocortical Carcinoma

ABSTRACT

Multiple endocrine neoplasia 1 (MEN1) syndrome is an autosomal dominant syndrome comprising a triad of pancreatic, pituitary, and parathyroid tumors. Adrenal cortical carcinoma occurs rarely in MEN1 syndrome. Here, we have presented a case of a 62-year-old woman with adrenal mass and elevated serum parathormone levels, who underwent 68Ga-DOTANOC PET/CT. 68Ga-DOTANOC PET/CT showed intense tracer concentration in the left adrenal mass and lesions in the liver, pancreas, and peritoneum. Biopsy of the peritoneal deposit revealed metastatic adrenocortical carcinoma, and further genetic testing showed MEN1 mutation.

18F-FDG PET/CT Imaging of Adrenal Liposarcoma

Liposarcoma is a common soft tissue sarcoma in retroperitoneum, but adrenal liposarcoma is rare. We here described a 61-year-old man with left-upper-quadrant pain, hypertension, and weight loss. Abdominal CT showed a large, heterogeneously enhanced mass on the left adrenal area, which compressed the surrounding pancreas, spleen, and left kidney. Subsequent FDG PET/CT demonstrated heterogeneous uptake by the lesion. Postoperative pathological findings confirmed the diagnosis of adrenal liposarcoma.

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

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.

Metabolic and anatomic characteristics of benign and malignant adrenal masses on positron emission tomography/computed tomography: a review of literature

PET/CT with (18)F-fluorodeoxyglucose (FDG) or using different radiocompounds has proven accuracy for detection of adrenal metastases in patients undergoing cancer staging. It can assist the diagnostic work-up in oncology patients by identifying distant metastases to the adrenal(s) and defining oligometastatic disease that may benefit from targeted intervention. In patients with incidentally discovered adrenal nodules, so-called adrenal "incidentaloma" FDG PET/CT is emerging as a useful test to distinguish benign from malignant etiology. Current published evidence suggests a role for FDG PET/CT in assessing the malignant potential of an adrenal lesion that has been 'indeterminately' categorized with unenhanced CT, adrenal protocol contrast-enhanced CT, or chemical-shift MRI. FDG PET/CT could be used to stratify patients with higher risk of malignancy for surgical intervention, while recommending surveillance for adrenal masses with low malignant potential. There are caveats for interpretation of the metabolic activity of an adrenal nodule on PET/CT that may lead to false-positive and false-negative interpretation. Adrenal lesions represent a wide spectrum of etiologies, and the typical appearances on PET/CT are still being described, therefore our goal was to summarize the current diagnostic strategies for evaluation of adrenal lesions and present metabolic and anatomic appearances of common and uncommon adrenal lesions. In spite of the emerging role of PET/CT to differentiate benign from malignant adrenal mass, especially in difficult cases, it should be emphasized that PET/CT is not needed for most patients and that many diagnostic problems can be resolved by CT and/or MR imaging.