Merkel cell carcinoma: Critical review with guidelines for multidisciplinary management

Merkel cell carcinoma (MCC) is a relatively rare cutaneous malignancy that occurs predominantly in the older white population. The incidence of MCC appears to have tripled during the past 20 years; an increase that is likely to continue because of the growing number of older Americans. The pathogenesis of MCC remains largely unknown. However, ultraviolet radiation and immunosuppression are likely to play a significant pathogenetic role. Many questions currently remain unanswered regarding the biologic behavior and optimal treatment of MCC. Large, prospective, randomized studies are not available and are unlikely to be performed because of the rarity of the disease. The objective of this review was to provide a comprehensive reference for MCC based on a critical evaluation of the current data. The authors investigated the importance of sentinel lymph node biopsy as a staging tool for MCC to assess the status of the regional lymph node basin and to determine the need for additional therapy to the lymph node basin. In an attempt to standardize prospective data collection with the intention to define prognostic indicators, the authors also present histopathologic profiles for primary MCC and sentinel lymph nodes. The controversies regarding the appropriate surgical approach to primary MCC, the use of adjuvant radiation therapy, and the effectiveness of adjuvant chemotherapy were examined critically. Finally, the authors have provided treatment guidelines based on the available evidence and their multidisciplinary experience. Cancer 2007. © 2007 American Cancer Society.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/56047/1/22765_ftp.pd

Highly Sensitive Dispersion Map Extraction from Highly Nonlinear Fibers Using BOTDA Probing of Parametric Amplification

The performance of devices based on highly nonlinear fibers (HNLF) can be drastically impeded by even tiny fluctuations of the zero dispersion wavelength (ZDW) along the fiber. Being able to measure ZDW fluctuations along an HNLF is therefore essential for the design of efficient nonlinear optics based devices such as fiber optical parametric amplifiers (FOPA), regenerators and limiters. Different schemes using complex distributed sensing of localized nonlinear interactions have been used in order to derive the ZDW fluctuations along the fiber [1-2]. In [3], the distributed gain of a pulsed pump FOPA along an HNLF was measured using a Brillouin Optical-Time Domain Analysis (BOTDA) based technique. In this paper, by improving the experimental scheme, we have been able to measure the FOPA gain along the fiber with low noise, which enabled us to derive ZDW fluctuations as low as 0.02 nm along HNLFs with 2 meters longitudinal resolution. The experimental setup is depicted in Fig. 1(a). Compared to [2], both the FOPA pump and signal are pulsed before being injected into the HNLF. The FOPA signal also acts as a BOTDA pump. Using an electro-optic modulator, two carrier-suppressed sidebands are symmetrically generated below and above the BOTDA pump (FOPA signal) frequency. The detuning between the sidebands and the BOTDA pump frequency is set to be equal to the Brillouin frequency shift of the fiber. The two sidebands are launched at opposite end of the fiber designated as cw probes 1 and 2. Thus the Brillouin interaction with the BOTDA pump will lead to a gain on th

Analytical Model for the Extraction of Flaw-Induced Current Interactions for SQUID NDE

Incorporating an analytical approach to simulate the interaction of a series of long cracks and the induced current of a double-D excitation coil, we have developed a model-based method to do precise detection of the positions of the cracks in a metallic structure by using eddy-current superconducting quantum interference device (SQUID) nondestructive evaluation (NDE) measurements. Conventionally, the structure of the defects is found by iteratively solving a numerical forward problem, which is usually based on finite-element, boundary-element, or volume-integral method. This, however, incurs a heavy numerical burden, as every time the forward problem is to be solved, a rigorous numerical model should be inevitably employed to extract the complex distribution pattern of the induced current encountering defects of the structure. In this paper, an analytical approach is used for the modeling of the interaction of the induced current and a series of cracks in the sample. It duly considers the distribution of the induced current in the flawed samples, does not call for extremely high computational resource, and thus permits efficient NDE as the forward problem can be solved within a reasonable time. Here, a high-T-c first-order radio-frequency SQUID gradiometer is employed as the magnetic sensor of the NDE system to scan the samples with different cracks. The accuracy of the proposed algorithm is verified by having the extracted shape of the defects obtained by applying the proposed algorithm on the SQUID NDE measurements against the actual cracks