Uncovering the Uncommon: An 81-Year-Old Woman With Elevated Carcinoembryonic Antigen (CEA) but Normal Calcitonin Levels Diagnosed With Medullary Thyroid Carcinoma.

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor. However, non-elevated calcitonin levels have been reported in the literature. We present the case of an 81-year-old woman with chronic elevations in carcinoembryonic antigen (CEA) levels for the past 15 years, despite normal calcitonin levels, who was ultimately diagnosed with MTC. The patient had a remote history of breast cancer and presented with symptoms of unintentional weight loss, fatigue, and joint pain. A positron emission tomography (PET) scan revealed low fluorodeoxyglucose (FDG) uptake in partially calcified thyroid nodules, and fine needle aspiration cytology was consistent with medullary carcinoma. The patient underwent total thyroidectomy, with pathology revealing a pT1aN0M0 medullary thyroid microcarcinoma with negative margins. After thyroidectomy, CEA levels decreased to within the normal range, and calcitonin levels remained normal. This case highlights the importance of considering MTC in patients with unexplained chronic elevations in CEA levels, even with normal calcitonin levels.

Phase II study of eribulin mesylate, a halichondrin B analog, in patients with metastatic breast cancer previously treated with an anthracycline and a taxane.

PURPOSE: Eribulin mesylate (E7389), a nontaxane microtubule dynamics inhibitor, is a structurally simplified, synthetic analog of the marine natural product halichondrin B. This open-label, single-arm, phase II study evaluated efficacy and tolerability of eribulin in heavily pretreated patients with metastatic breast cancer (MBC). METHODS: MBC patients who were previously treated with an anthracycline and a taxane received eribulin mesylate (1.4 mg/m(2)) as a 2- to 5-minute intravenous (IV) infusion on days 1, 8, and 15 of a 28-day cycle. Because of neutropenia (at day 15), an alternative regimen of eribulin on days 1 and 8 of a 21-day cycle was administered. The primary end point was overall response rate. RESULTS: Of the 103 patients treated, the median number of prior chemotherapy regimens was four (range, one to 11 regimens). In the per-protocol population (n = 87), eribulin achieved an independently reviewed objective response rate (all partial responses [PRs]) of 11.5% (95% CI, 5.7 to 20.1) and a clinical benefit rate (PR plus stable disease > or = 6 months) of 17.2% (95% CI, 10.0 to 26.8). The median duration of response was 171 days (5.6 months; range, 44 to 363 days), the median progression-free survival was 79 days (2.6 months; range, 1 to 453 days), and the median overall survival was 275 days (9.0 months; range, 15 to 826 days). The most common drug-related grades 3 to 4 toxicities were as follows: neutropenia, 64%; leukopenia, 18%; fatigue, 5%; peripheral neuropathy, 5%; and febrile neutropenia, 4%. CONCLUSION: Eribulin demonstrated activity with manageable tolerability (including infrequent grade 3 and no grade 4 neuropathy) in heavily pretreated patients with MBC when dosed as a short IV infusion on days 1 and 8 of a 21-day cycle.