The surgical management of locally advanced well-differentiated thyroid carcinoma. Changes over the years according to the AJCC 8th edition Cancer Staging Manual

Background: Well-differentiated thyroid carcinoma is defined as locally advanced in the presence of an extra thyroid extension, e.g., when the surrounding structures such as the trachea, larynx, esophagus and main blood vessels are invaded by cancer. The 8th edition AJCC Cancer Staging Manual states that this is the main characteristic to evaluate for the staging and consequently for the prognosis in patients over 55 years old. Main body: Distinguishing different forms of locally advanced thyroid cancer is essential, and the various anatomical structures and the clinical and therapeutic consequences must be taken into account. An accurate diagnosis of the organs invaded by thyroid cancer is necessary for the planning of surgical treatment, and both aspects are crucial to improving the patients' survival. Patients affected by thyroid cancer with extra thyroid extension have a poor prognosis and the removal of the entire neoplasm represents a key factor for better disease-free survival. Conclusions: We discuss the changes introduced by the 8th edition AJCC Cancer Staging Manual, in terms of the diagnostic and surgical management of extra thyroid extension, in patients affected by papillary and follicular thyroid cancer

Discrete and Conservative Factorizations in Fib(B)

We focus on the transfer of some known orthogonal factorization systems from Cat to the 2-category Fib(B) of fibrations over a fixed base category B: the internal version of the comprehensive factorization, and the factorization systems given by (sequence of coidentifiers, discrete morphism) and (sequence of coinverters, conservative morphism) respectively. For the class of fibrewise opfibrations in Fib(B) , the construction of the latter two simplify to a single coidentifier (respectively coinverter) followed by an internal discrete opfibration (resp. fibrewise opfibration in groupoids). We show how these results follow from their analogues in Cat, providing suitable conditions on a 2-category C, that allow the transfer of the construction of coinverters and coidentifiers from C to FibC(B)

Simultaneous Quantitative MRI Mapping of T1, T2* and Magnetic Susceptibility with Multi-Echo MP2RAGE.

The knowledge of relaxation times is essential for understanding the biophysical mechanisms underlying contrast in magnetic resonance imaging. Quantitative experiments, while offering major advantages in terms of reproducibility, may benefit from simultaneous acquisitions. In this work, we demonstrate the possibility of simultaneously recording relaxation-time and susceptibility maps with a prototype Multi-Echo (ME) Magnetization-Prepared 2 RApid Gradient Echoes (MP2RAGE) sequence. T1 maps can be obtained using the MP2RAGE sequence, which is relatively insensitive to inhomogeneities of the radio-frequency transmit field, [Formula: see text]. As an extension, multiple gradient echoes can be acquired in each of the MP2RAGE readout blocks, which permits the calculation of [Formula: see text] and susceptibility maps. We used computer simulations to explore the effects of the parameters on the precision and accuracy of the mapping. In vivo parameter maps up to 0.6 mm nominal resolution were acquired at 7 T in 19 healthy volunteers. Voxel-by-voxel correlations and the test-retest reproducibility were used to assess the reliability of the results. When using optimized paramenters, T1 maps obtained with ME-MP2RAGE and standard MP2RAGE showed excellent agreement for the whole range of values found in brain tissues. Simultaneously obtained [Formula: see text] and susceptibility maps were of comparable quality as Fast Low-Angle SHot (FLASH) results. The acquisition times were more favorable for the ME-MP2RAGE (≈ 19 min) sequence as opposed to the sum of MP2RAGE (≈ 12 min) and FLASH (≈ 10 min) acquisitions. Without relevant sacrifice in accuracy, precision or flexibility, the multi-echo version may yield advantages in terms of reduced acquisition time and intrinsic co-registration, provided that an appropriate optimization of the acquisition parameters is performed

Fibred-categorical obstruction theory

We set up a fibred categorical theory of obstruction and classification of morphisms that specialises to the one of monoidal functors between categorical groups and also to the Schreier-Mac Lane theory of group extensions. Fu r t h e r applications are provided to crossed extensions and crossed bimodule butterflies, with in particular a classification of non-abelian extensions of unital associative algebras in terms of Hochschild cohomology

Fibered aspects of Yoneda's regular span

In this paper we start by pointing out that Yoneda's notion of a regular span S:X→A×B can be interpreted as a special kind of morphism, that we call fiberwise opfibration, in the 2-category Fib(A). We study the relationship between these notions and those of internal opfibration and two-sided fibration. This fibrational point of view makes it possible to interpret Yoneda's Classification Theorem given in his 1960 paper as the result of a canonical factorization, and to extend it to a non-symmetric situation, where the fibration given by the product projection Pr0:A×B→A is replaced by any split fibration over A. This new setting allows us to transfer Yoneda's theory of extensions to the non-additive analog given by crossed extensions for the cases of groups and other algebraic structures