Intraoperative frozen section as a reliable ancillary technique in salivary gland surgery: A cross sectional study

Background. Salivary glands tumours are uncommon, frequently benign lesions, prevalently located in the parotid gland (80%). Surgical decision making is based on the patient's history, examination findings, imaging and fine needle aspiration (FNA). FNA is a pre-operative method with good ability in detecting malignancy. During surgery, therefore, Frozen section (FS) can differentiate benign lesions from malignant tumours, to reduce incorrect treatments, to increase the chances of conservative surgery and to better evaluate surgical margins. The aim of our study is to demonstrate the accuracy of the FS procedure in surgery of the salivary glands and to stress the need for dedicated pathology units specialized in lesions of the oral cavity. Methods. The study included 499 patients who underwent surgery from May 2005 and October 2014. An intra-operative frozen section procedure was done for 288 of them. All frozen sections were compared with the final results. The cases were classified by site, nature of the lesion and histotype, according to the WHO classification. Comparison was made between the intra-operative and the definitive diagnosis. Results. Of the 288 FS procedures, 259 were for neoplastic lesions, 199 of which benign and 60 malignant, and 29 for non-neoplastic lesions. Of the 259 neoplastic FS results, 2 were shown to be false positives and 2 were diagnosed as different malignant types. Of the 29 non-neoplastic FS results, 4 were false negatives. Conclusions. Our results showed that the accuracy of frozen section procedure is 98% for salivary glands tumors. The highest concordance between frozen section and the definitive diagnosis was for inflammatory processes (99%), pleomorphic adenoma (98%), Warthin's tumor (97%) and malignant neoplasms (96%). In conclusion, based on these findings, frozen section of the salivary glands may be proposed as a routine procedure and should be used in decision-making

Thyroglossal duct carcinoma: Report of a case

Summary. Aim: Thyroglossal duct carcinoma (TDCa) is a rare malignant tumor arising within a thyroglossal duct remnant (TDR) or a thyroglossal duct cyst (TDC). Controversies exist regarding its origin: whether it represents a metastatic lesion of a primary thyroid cancer or a â\u80\u9cde novoâ\u80\u9d origin. Patients and methods: Man with a visible and palpable subhyoid mass. Preoperative ultrasound scan and US-guided fine-needle aspiration cyology revealed suspicious papillary carcinoma in the TDC and thyroid nodules. Surgery consisted in removal of the hyoid bone and total thyroidectomy. Results: Histopathologic examination revealed papillary TDCa and a focus of papillary var. follicular microcarcinoma in the thyroid gland. Conclusions: Ultrasound scan with fine-needle aspiration cytology is beneficial in the preoperative diagnosis of carcinoma in TDC. Surgery is an adequate treatment for TDCa and the prognosis for TDCa is excellent. Adjuvant radioactive iodine and post-operative L-thiroxine suppressive therapy are appropriate in these cases. Our experience confirms the controversies about the origin of TDCa

Patterning Magnonic Structures via Laser Induced Crystallization of Yittrium Iron Garnet

The fabrication and integration of high-quality structures of Yttrium Iron Garnet (YIG) is critical for magnonics. Films with excellent properties are obtained only on single crystal Gadolinium Gallium Garnet (GGG) substrates using high-temperature processes. The subsequent realization of magnonic structures via lithography and etching is not straightforward as it requires a tight control of the edge roughness, to avoid magnon scattering, and planarization in case of multilayer devices. In this work a different approach is described based on local laser annealing of amorphous YIG films, avoiding the need for subjecting the entire sample to high thermal budgets and for physical etching. Starting from amorphous and paramagnetic YIG films grown by pulsed laser deposition at room temperature on GGG, a 405 nm laser is used for patterning arbitrary shaped ferrimagnetic structures by local crystallization. In thick films (160 nm) the laser induced surface corrugation prevents the propagation of spin-wave modes in patterned conduits. For thinner films (80 nm) coherent propagation is observed in 1.2 mu m wide conduits displaying an attenuation length of 5 mu m that is compatible with a damping coefficient of approximate to 5 x 10-3. Possible routes to achieve damping coefficients compatible with state-of-the art epitaxial YIG films are discussed.Arbitrary shaped magnonic structures can be patterned in amorphous thin films of Yttrium Iron Garnet (YIG) by laser induced local crystallization, with no need for etching and without exposing the entire sample to a high thermal budget. Spin wave attenuation distances of approximate to 5 mu m are measured in patterned conduits, compatible with a damping coefficient of 5.8 +/- 0.4 x 10-3. imag