Epidemiological and clinical features of lymphoproliferative diseases in the head and neck region

Background. Lymphomas are a heterogeneous group of the lymphoid and hematopoietic system tumors. Neoplastic process often develops in head and neck area, including the integumentary tissues, orbit, nasal cavity, paranasal sinuses, oral cavity, pharynx, salivary glands, thyroid gland, as well as neck lymph nodes. The difficulties of head and neck lymphomas diagnosis are significant, since very often there is a combined non-tumor pathology. The high heterogeneity of lymphomas in the head and neck area requires structuring knowledge about their epidemiology and clinical manifestations.Objective: to study the epidemiological and clinical features of the head and neck lymphoproliferative diseases, which will lead to an improvement in diagnostic quality of this nosology's.Materials and methods. The frequency of head and neck lymphoproliferative diseases detection was estimated based on the study of epicrisis and clinical data of 174 patients hospitalized at the N.N. Blokhin National Medical Research Center of Oncology in the period from 2000 to 2020.Results. Taking into account the modern clinical and morphological classification of lymphomas of the World Health Organization (2017), information about the features of localization, characteristic signs of extranodal foci and lymph nodes is presented. Detection frequency of various subtypes non-Hodgkin's and Hodgkin's lymphomas were determined on a sufficient cohort of patients.Conclusion. Based on the analysis of clinical and morphological features of head and neck lymphomas, epidemiological and clinical features are described in detail, and differences in the symptoms and clinical manifestations of non-Hodgkin's and Hodgkin's lymphomas with a predominant head and neck involvement are revealed

Solving a Deconvolution Problem in Photon Spectrometry

We solve numerically a deconvolution problem to extract the undisturbed spectrum from the measured distribution contaminated by the finite resolution of the measuring device. A problem of this kind emerges when one wants to infer the momentum distribution of the neutral pions by detecting the it decay photons using the photon spectrometer of the ALICE LHC experiment at CERN {[}1]. The underlying integral equation connecting the sought for pion spectrum and the measured gamma spectrum has been discretized and subsequently reduced to a system of linear algebraic equations. The latter system, however, is known to be ill-posed and must be regularized to obtain a stable solution. This task has been accomplished here by means of the Tikhonov regularization scheme combined with the L-curve method. The resulting pion spectrum is in an excellent quantitative agreement with the pion spectrum obtained from a Monte Carlo simulation. (C) 2010 Elsevier B.V. All rights reserved