A 58-year-old male with no significant past medical history presented to an outside institution with vague fatigue and left upper quadrant pain. A CT scan revealed a 15 x 9 x 9 cm left retroperitoneal mass as well as a 3 cm gastric tumor (Figure 1). Biopsy of the retroperitoneal mass was consistent with adrenocortical carcinoma. He underwent a left adrenalectomy and partial gastrectomy with pathology confirming ACC and a gastrointestinal stromal tumor (GIST) of the stomach. He then began Mitotane, an adrenolytic, for 2.5 years and adjuvant radiation to the adrenal bed.
His surveillance was performed at outside institutions, and his scans remained negative for the following 4 years. A follow-up surveillance CT scan done 6 years after diagnosis revealed a 9.5 x 8.7 cm right hepatic mass. This was followed with an MRI at that time that confirmed the presence of suspicious liver metastases (Figure 2). Right hepatectomy was attempted at an outside institution but aborted due to the suspected presence of “miliary disease” based on the surgeon’s visualization of small plaque-like lesions on the liver surface. Therefore, only a segment 5 hepatic nodule was resected for permanent section and genetic sequencing and a cholecystectomy was performed. Review of the patient’s available images from that time showed no left hepatic lobe lesions visible on imaging. Per the outside surgery report, the patient did receive an [¹⁸F]Fluorodeoxyglucose ([¹⁸F]FDG) positron emission tomography/computed tomography (PET/CT) in addition to the MRI prior to surgery, which showed no extrahepatic disease (images not available).
After discussion of the case at our multidisciplinary tumor board, the decision was made for systemic therapy as well as liver directed therapy. The patient started an EDP chemotherapy schedule (Etoposide, Doxorubicin, and Cisplatin). He then underwent visceral angiogram workup which demonstrated collateral supply to a portion of the right hepatic lobe tumors by right inferior phrenic artery branch (Figure 3). A hepatopulmonary shunt of 3% was observed on planar scintigraphy and single-photon emission computed tomography (SPECT) (Figure 4) after administration of 214.6 MBq [99mTc]technetium-macroaggregated albumin ([99mTc]Tc-MAA, Drax Image MAA kit; 99.7% purity) into the right hepatic artery. The hepatic volumes were manually calculated using the native basic segmentation tool from General Electric’s Picture Archiving and Communication Systems: total 2084 cm3, volume of liver to be treated 1537 cm3, and volume of tumor in the region 654 cm3. As there is paucity of data on what is the most appropriate dose to deliver to these tumors, a modified BSA model calculated the required activity at 1.8 GBq using an estimated lung mass of 1 kg. However, since these tumors can be radioresistant, we decided to increase the activity to 2 GBq. This would have given an estimated dose of 105 Gy to the tumor by partition model, using a T/N ratio of 4, 26 Gy to the normal liver, and 3 Gy to the lungs.
On the procedure day, the patient first underwent bland embolization of the inferior branch of the right inferior phrenic artery using 900 µm Embosphere microspheres (Merit, Utah, USA) to cause redistribution of flow into the tumors along the surface of the right hepatic lobe from the right hepatic artery (Figure 5). Subsequent 90Y SIR-sphere (Sirtex Medical Inc., Massachusetts, USA) resin embolization of the right hepatic artery was performed (Figure 6) with a total administered activity to the perfused volume of 2.11 GBq. The patient developed post-procedure adrenal crisis in the recovery room manifested by abdominal pain and diaphoresis, and was treated with 20 mg of dexamethasone followed by 60 mg intravenous hydrocortisone every 6 hours. After admission and steroid therapy, he was then discharged in stable condition on post-procedure day 3.
The patient’s 1-month follow-up MRI showed decrease in the size of the multiple right hepatic metastatic lesions including the small lesions on the liver surface with no new sites of disease. Specifically, no lesions were seen in the left hepatic lobe. 3-month post-radioembolization [¹⁸F]FDG PET/CT showed no residual disease and no recurrent left adrenal mass (Figure 7). 4- and 5-month post-radioembolization MRI showed continued decrease in size and enhancement of the right hepatic lesions (Figure 8). Despite the reassuring imaging findings, the patient requested surgical resection of the right hepatic lesions as the data is sparse on the effect of SIRT on ACC hepatic metastases. In conjunction with the multidisciplinary tumor board, surgery was deemed reasonable as the disease was limited to the right hepatic lobe and no miliary disease was seen on imaging. Hence, 7 months after radioembolization, he had partial right hepatectomy at an outside institution with pathology demonstrating no viable tumor including in the resection margin. 1-month post resection MRI showed no residual hepatic lesions (Figure 9). The patient was in observation and surveillance with regular lab work for adrenal insufficiency, including renin, dehydroepiandrosterone sulfate (DHEAS), and adrenocorticotropic hormone (ACTH). He declined adjuvant mitotane therapy due to quality-of-life concerns and previous side effects. An incidental periportal lymph node measuring 1 cm short axis was found on CT chest 8 months post-resection (15 months post-radioembolization), which was subsequently found to be metastatic ACC on surgical pathology. Although he developed metastatic periportal lymphadenopathy, the patient is currently 16 months post-surgical resection and 23 months post-radioembolization with no hepatic recurrence.