Surgical treatment result of giant thyroid tumor: Case series in Vietnam.

INTRODUCTION: Giant thyroid tumors can be associated with severely compressive symptoms and surgery is inevitable for treatment strategy. However, the risk of surgical complications is higher as well as the duration of operation may be longer than those of small thyroid tumors. PRESENTATION OF CASES: Two patients with large neck tumors were admitted with history of thyroid goiters for more than 10 years. Recently, the patients have complained of worsening compressive symptoms including dyspnea and dysphagia. Imaging work-up indicated a deviation and compression of trachea. Both patients underwent either lobectomy or thyroidectomy and were discharged without any complications. Final histological results were thyroid adenoma in both cases. CONCLUSION: Surgical management is considered as primary treatment for most patients with giant thyroid tumors. It is necessary to be aware of complications and careful dissection to archive a good outcome.

Redetermined crystal structure of α-dl-me-thio-nine at 340†K.

Two forms, α and ß, are known for the racemic amino acid dl-me-thio-nine, C5H11NO2S. The phase transition between them, taking place around 326 K, is associated with sliding at the central inter-faces of the hydro-phobic regions in the crystal, leaving the hydrogen-bonding pattern unperturbed. For the high-temperature α phase, only a structure of rather low quality has been available [R factor = 0.118, no H-atom coordinates; Taniguchi et al. (1980 ▶). Bull. Chem. Soc. Jpn, 53, 803-804]. We here present accurate structural data for this polymorph [R(F) = 0.049], which are compared with other related amino acid structures with similar properties. We report for the first time that the side chain of this phase has a minor disorder component [occupancy 0.0491 (18)] with a gauche+ rather than a gauche- conformation for the N-C-C-C group. In the crystal of the title compound, N-H⋯O hydrogen bonds link the mol-ecules into (100) sheets.