Introduction: Adrenocortical carcinoma (ACC) is an aggressive malignancy with high rates of recurrence even after surgical resection. Surgery remains the mainstay of treatment, while adjuvant options are limited. Mitotane is the only approved systemic therapy. Current guidelines recommend stereotactic body radiotherapy (SBRT) alongside adjuvant mitotane therapy in Rx, R1, R2 resections and in locally advanced disease. Case: We present a case of a 40-year-old female who presented with abdominal pain and was found to have a large heterogeneous left adrenal mass measuring 8.2 × 8.5 × 9.5 cm (Hounsfield Unit 63) on computed tomography (CT) imaging. Clinically, she was obese with a body mass index of 33.7 kg/m². No discriminatory feature of Cushing’s was present. Hormonal evaluation demonstrated autonomous cortisol secretion with failure of suppression on both overnight and low-dose dexamethasone suppression tests at 301 nmol/L and 313.6 nmol/L, respectively. DHEA, testosterone, and urinary metanephrine were within range. Hemoglobin A1c was 6.6%. She underwent open left adrenalectomy. Intra-operatively, a 12 × 10 cm adrenal tumor was identified with multiple areas of tumor rupture and spillage during mobilization. HPE confirmed high-grade ACC with high Weiss score of 8, Ki-67 index 60–80%, and mitotic count 54/50 hpf (pT2Nx). Post-operative CT imaging demonstrated a residual soft tissue lesion in the left adrenal bed (largest diameter 3.8 cm) with fluorodeoxyglucose avidity. We commenced adjuvant mitotane therapy, titrated to 2 g TDS with supraphysiological hydrocortisone replacement. Mitotane level was within therapeutic range (16 mcg/mL). She was deemed unsuitable for repeat surgery due to the proximity of the residual mass to the adjacent vessel and was planned for SBRT therapy after a multidisciplinary team discussion. Conclusion High-risk ACC with suspected residual disease remains a therapeutic challenge. While mitotane remains the cornerstone of adjuvant therapy, SBRT may represent a promising adjunctive local treatment modality in carefully selected patients. Further studies are required to define its role in improving local control and outcomes in ACC.
Adrenocortical Carcinoma ; Mitotane