Tumores de colisión en tiroides: carcinoma papilar y metástasis de carcinoma renal a células claras

Collision tumors are rare neoplasms, they require combination therapy for the treatment of each tumor independently. We describe the case of a 55 year old patient diagnosed with clear cell renal cell carcinoma; whole body computed tomography reported pulmonary and hepatic nodules suggestive of metastatic disease. Oncology indicated sunitib therapy. Eleven months later, evaluation with computed tomography reported multiple thyroid nodules. Total thyroidectomy was performed, with anatomo-pathological report: papillary thyroid carcinoma and metastases of clear cell renal cell carcinoma. He received ablation with 80 mCi of radioactive iodine (I-131); then thyroid hormone suppressive therapy with levothyroxine.Los tumores de colisión son neoplasias poco comunes, requieren terapias combinadas tratando independientemente cada tumor. La presentación en la glándula tiroides es rara. Reportamos el caso de un paciente de 55 años con diagnóstico de carcinoma renal a células claras; la tomografía corporal reportó nódulos pulmonares y hepáticos sugestivos de metástasis. Oncología indicó tratamiento con sunitinib. Once meses después, la tomografía de control reportó múltiples nódulos tiroideos. Se realizó tiroidectomía total, con informe anatomopatológico: carcinoma papilar de tiroides y metástasis de carcinoma renal a células claras. Recibió ablación con 80 mCi de iodo 131; luego hormonosupresión con levotiroxina

A coarse-to-fine approach to prostate boundary segmentation in ultrasound images

BACKGROUND: In this paper a novel method for prostate segmentation in transrectal ultrasound images is presented. METHODS: A segmentation procedure consisting of four main stages is proposed. In the first stage, a locally adaptive contrast enhancement method is used to generate a well-contrasted image. In the second stage, this enhanced image is thresholded to extract an area containing the prostate (or large portions of it). Morphological operators are then applied to obtain a point inside of this area. Afterwards, a Kalman estimator is employed to distinguish the boundary from irrelevant parts (usually caused by shadow) and generate a coarsely segmented version of the prostate. In the third stage, dilation and erosion operators are applied to extract outer and inner boundaries from the coarsely estimated version. Consequently, fuzzy membership functions describing regional and gray-level information are employed to selectively enhance the contrast within the prostate region. In the last stage, the prostate boundary is extracted using strong edges obtained from selectively enhanced image and information from the vicinity of the coarse estimation. RESULTS: A total average similarity of 98.76%(± 0.68) with gold standards was achieved. CONCLUSION: The proposed approach represents a robust and accurate approach to prostate segmentation

Characterization of Human Osteoarthritic Cartilage Using Optical and Magnetic Resonance Imaging

Purpose: Osteoarthritis (OA) is a degenerative disease starting with key molecular events that ultimately lead to the breakdown of the cartilage. The purpose of this study is to use two imaging methods that are sensitive to molecular and macromolecular changes in OA to better characterize the disease process in human osteoarthritic cartilage. Procedures: Human femoral condyles were collected from patients diagnosed with severe OA during total knee replacement surgeries. T1ρ and T2 magnetic resonance measurements were obtained using a 3-Tesla whole body scanner to assess macromolecular changes in the damaged cartilage matrix. Optical imaging was performed on specimens treated with MMPSense 680 to assess the matrix metalloproteinase (MMP) activity. A linear regression model was used to assess the correlation of MMP optical data with T 1ρ magnetic resonance (MR) measurements. Slices from a representative specimen were removed from regions with high and low optical signals for subsequent histological analysis. Results: All specimens exhibit high T1ρ and T2 measurements in the range of 48–75 ms and 36– 69 ms, respectively. They also show intense photon signals (0.376 to 7.89×10 −4 cm 2) from th

The difference that ‘one drop’ makes: Mexican and African Americans, mixedness and racial categorisation in the early twentieth century

Using archival materials, I will examine how the mixed ancestry of African and Mexican Americans was treated, both in law and discourse, in distinctly contrasting ways in the early 20th century. I will argue that black and Mexican subjects were positioned in qualitatively different ways in relation to whiteness. Furthermore, the singular treatment of ‘black blood’ as a social toxin, a construction emerging within the specific circumstances of American slavery, also informed the subjective positioning of Mexicans, as well as shaping some Mexican Americans’ responses to racism