André Bandiera de Oliveira Santos

Micro-Raman spectroscopic study of thyroid tissues.

Thyroid carcinomas are the most common endocrine malignancy. Inconclusive results for the analysis of malignancies are an issue in the diagnosis of thyroid carcinomas; 20% of thyroid cancer diagnoses are indeterminate or suspicious, resulting in a surgical procedure without immediate need. The use of Raman spectroscopy may help improve the diagnosis of thyroid carcinoma. In this study, 30 thyroid samples, including normal thyroid, goiter and thyroid cancer, were analyzed by confocal Raman spectroscopy. Principal component analysis (PCA), linear discriminant analysis (LDA) with cross validation and binary logistic regression (BLR) analysis were applied to discriminate among tissues. Significant discrimination was observed, with a consistent rate of concordant pairs of 89.2% for normal thyroid versus cancer, 85.7% for goiter versus cancer and 80.6% for normal thyroid versus goiter using just the amide III region. Raman spectroscopy was thus proven to be an important and fast tool for the diagnosis of thyroid tissues. The spectral region of 1200-1400cm-1 discriminated normal versus goiter tissues despite the great similarity of these tissues.

Tumor volume as an independent predictive factor of worse survival in patients with oral cavity squamous cell carcinoma

The purpose of the present study was to investigate the role of tumor volume in the prognosis of patients with oral cavity squamous cell carcinoma (SCC).

Tireoidectomia vídeo assistida: experiência de 120 casos

BACKGROUND: The objective of this paper is to describe a 120 cases experience in the video-assisted technique, performed by the same surgical team. METHODS: Between september 2004 and february 2006, 120 video-assisted thyroidectomies has been performed - 119 females and 1 male. Age: 19 - 58, median 34 years. Indications: suspicion of malignancy, without any cervical surgery, radiotherapy, thyroid volume under 20 cc and nodules under 3 cm. RESULTS: Surgery time: 25 - 180, median time 85 minutes for total and 59 minutes for parcial thyroidectomy. The incision: 1,6 - 3,5cm, median 2,5cm. Four conversions to conventional technique are related. Nerve palsy was observed in 5,8%. There was no hypoparathyroidism or hematoma in this series. All patients were released in the first postoperative day. CONCLUSION: The video assisted approach is a safe procedure, and its complication index is similar to the conventional technique, with advantages in incision size and postoperative evolution. However, more studies are needed to confirm these findings.

Papillary carcinoma in thyroglossal duct cyst: role of fine needle aspiration and frozen section biopsy to guide surgical approach

Thyroglossal duct cyst is the most common anomaly in the embryogenesis of the thyroid gland [1]. However, carcinoma is uncommon, occurring in *1 % of all thyroglossal duct cysts, particularly papillary carcinoma [1, 2]. Although controversial, it is proposed that Sistrunk’s operation should be followed by total thyroidectomy [1]. 20 % of the papillary carcinomas in thyroglossal duct cysts may present concomitant thyroid cancer. Therefore, preoperative identification of papillary carcinoma in the thyroglossal duct cyst would allow an appropriated decision on the extension of surgery. We describe clinical features and diagnostic evaluations of benign and malignant thyroglossal duct cysts followed in the same institution. Materials and methods

Which features of advanced head and neck basal cell carcinoma are associated with perineural invasion

INTRODUCTION Perineural invasion is a unique route for tumor dissemination. In basal cell carcinomas, the incidence is low, but increases in advanced cases. Its importance is recognized but not fully understood. OBJECTIVE To compare head and neck basal cell carcinomas with and without perineural invasion. METHODS A retrospective medical chart review of multidisciplinary surgeries for basal cell carcinomas that required a head and neck surgery specialist in a tertiary referral center was performed. Clinical-demographics and histopathological features were analyzed. RESULTS Of 354 cases, perineural invasion was present in 23.1%. Larger tumors and morpheaform subtype were statistically related to perineural invasion. Nodular and superficial subtypes were less frequent in positive cases. No significant difference was found in gender, age, ulceration, location, and mixed histology. CONCLUSION In this series of selected patients with basal cell carcinomas submitted to major resections, perineural invasion was clearly related to morpheaform subtype and to larger tumors. Other classically associated features, such as location in high-risk mask zone of the face, male gender and mixed histology, were not so strongly linked to perineural invasion.

Biochemical and molecular characterization of thyroid tissue by micro-Raman spectroscopy and gene expression analysis

Thyroid carcinomas represent the main endocrine malignancy and their diagnosis may produce inconclusive results. Raman spectroscopy and gene expression analysis have shown excellent results on the differentiation of carcinomas. This study aimed to improve the discrimination between different thyroid pathologies combining of both analyses. A total of 35 thyroid tissues samples including normal tissue (n=10), goiter (n=10), papillary (n=10) and follicular carcinomas (n=5) were analyzed. Confocal Raman spectra was obtain by using a Rivers Diagnostic System, 785 nm laser excitation and CCD detector. The data was processed by the software Labspec5 and Origin 8.5 and analyzed by Minitab® program. The gene expression analysis was performed by qRT-PCR technique for TG, TPO, PDGFB, SERPINA1, LGALS3 and TFF3 genes and statistically analyzed by Mann-Whitney test. The confocal Raman spectroscopy allowed a maximum discrimination of 91.1% between normal and tumor tissues, 84.8% between benign and malignant pathologies and 84.6% among carcinomas analyzed. Significant differences was observed for TG, LGALS3, SERPINA1 and TFF3 genes between benign lesions and carcinomas, and SERPINA1 and TFF3 genes between papillary and follicular carcinomas. Principal component analysis was performed using PC1 and PC2 in the papillary carcinoma samples that showed over gene expression when compared with normal sample, where 90% of discrimination was observed at the Amide 1 (1655 cm-1), and at the tyrosine spectra region (856 cm-1). The discrimination of tissues thyroid carried out by confocal Raman spectroscopy and gene expression analysis indicate that these techniques are promising tools to be used in the diagnosis of thyroid lesions.