5-Fluorouracil for Invasive pituitary neuroendocrine tumor
Nelson's syndrome is considered a severe side effect that can occur after total bilateral adrenalectomy in patients with Cushing's disease. It usually presents with clinical manifestations of an enlarging pituitary tumor including visual and cranial nerve alterations, and if not treated, can cause death through local brain compression or invasion. The first therapeutic option is surgery but in extreme cases of inaccessible or resistant aggressive pituitary tumors; the off-label use of chemotherapy with capecitabine and temozolomide can be considered. However, the use of this treatment is controversial due to adverse events, lack of complete response, and inability to predict results. Mirallas et al. present the case of a 48-year-old man diagnosed with Nelson's syndrome with prolonged partial response and significant clinical benefit to treatment with capecitabine and temozolomide 1).
A survey confirms that TMZ is established as first-line chemotherapeutic treatment of APT/PC. Clinically functioning tumours, low MGMT and concurrent radiotherapy were associated with a better response. The limited long-term effect of TMZ and the poor efficacy of other drugs highlight the need to identify additional effective therapies. 2).
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