Nivolumab-induced hypophysitis in a patient with advanced malignant melanoma.

The anti-programmed cell death-1 monoclonal antibody (mab), nivolumab has recently been approved for the treatment of unresectable or metastatic malignant melanoma and non-small-cell lung cancers in Japan. Ipilimumab, an anti-cytotoxic T lymphocyte antigen-4 mab for malignant melanoma that was approved earlier than nivolumab in Western countries, is known to frequently cause endocrine immune-related adverse events such as hypophysitis and thyroid dysfunction. We herein report a patient with advanced melanoma who appeared to develop hypophysitis as a consequence of the inhibition of PD-1 by nivolumab. One week after the 6th administration of nivolumab, the patient developed progressive fatigue and appetite loss. Laboratory data on admission for the 7th administration of nivolumab showed eosinophilia and hyponatremia. Since ACTH and cortisol levels were low, nivolumab was discontinued and a large dose of hydrocortisone (100 mg/d) was promptly administered intravenously. A magnetic resonance imaging scan revealed the mild enlargement of the anterior pituitary gland and thickening of the stalk with homogenous contrast. A detailed assessment of anterior pituitary functions with hypothalamic hormone challenges showed that hormonal secretions other than ACTH and TSH were normal. With a replacement dose of hydrocortisone (20 mg/d), the 7th administration of nivolumab was completed without exacerbating the patient's general condition. The present report provides the first detailed endocrinological presentation of nivolumab-induced hypophysitis showing the enlargement of the pituitary gland and stalk in a malignant melanoma patient in Japan. Oncologists and endocrinologists need to be familiar with potentially life-threatening hypophysitis induced by immune-checkpoint inhibitors.

A case of idiopathic portal hypertension associated with nodular regenerative hyperplasia-like nodule of the liver and mixed connective tissue disease.

A 51-year-old woman was diagnosed with mixed connective tissue disease (MCTD) in 2011. She underwent treatment with prednisolone. Her hepatobiliary enzyme level increased, and multiple nodules were found in both liver lobes in abdominal imaging studies. Ultrasonography revealed large and small hyperechoic lesions with indistinct or well-defined borders. No findings of classic hepatocellular carcinoma or liver cirrhosis were observed on contrast-enhanced computed tomography, but some nodules showed an enhanced effect of the central lesion that was characteristic of focal nodular hyperplasia (FNH) in an arterial phase. On gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging, slightly high-intensity nodules, 10-40mm in size, were observed on T1- and T2-weighted images. The nodules showed highest intensities in the hepatocyte phase and were enhanced with the uptake of Gd-EOB-DTPA as compared with the background liver. FNH was suspected based on the imaging findings, but we performed a liver tumor biopsy for differential diagnosis of the malignant lesion. Based on the immunohistopathological examination results, the final diagnosis was idiopathic portal hypertension associated with nodular regenerative hyperplasia (NRH)-like nodule of the liver. Benign nodular hepatocellular lesions are caused by abnormal hepatic circulation and were previously known as anomalous portal tract syndrome. Our case of atypical NRH with large nodules may be included in this disease entity. Here, we report a rare case of MCTD with NRH-like nodules and idiopathic portal hypertension with a review of literature.