ANALYSIS OF CANCER INCIDENCE AMONG EMPLOYEES OF SIBERIAN GROUP OF CHEMICAL ENTERPRISES

Background. One of the main directions in the field of ensuring radiation safety of “nuclear legacy” facilities is the assessment of radiation effects and most significant radiogenic risks in employees of nuclear enterprises and their descendants.Objective. Analysis of the cancer incidence among employees of the Siberian Group of Chemical Enterprises (SGCE) exposed to ionizing radiation in the course of their professional activities.Material and Methods. The actual values and standardized estimated risks of developing cancer among the SGCE workers occupationally exposed to ionizing radiation were calculated using generally accepted methods based on the information of the regional medical dosimetry registry of Seversk Biophysical Research Center of FMBA, containing updated data on all SGCE employees diagnosed with cancer (period from 01.01.1950 to 31.12.2015 inclusive). The control group consisted of workers who were not occupationally exposed to ionizing radiation.Results. Among the male personnel of the SGCE, the highest incidence of cancer of the digestive, respiratory, and skin organs (including melanoma) was observed in patients aged 50–59 and 70–79 years. Among the female workers, the highest cancer incidence was in the age group 40–49 years; cancer of the gastrointestinal tract, genital tract and breast was the most common. The cancer incidence rate in the SGCE workers who occupationally exposed to ionizing radiation was not higher that that observed in the control group. The median age of male cancer patients occupationally exposed to ionizing radiation was significantly lower than the median age of male cancer patients of the control group. In female cancer patients, a significant difference in the median age of cancer diagnosis was found only in relation to skin cancer. Both male and female SGCE personnel occupationally exposed to ionizing radiation was at high risk of certain cancers: among male patients – cancer of the mesothelium and soft tissues, genital organs, eyes and brain, as well as multiple primary tumors; among female patients – cancer of lips, oral cavity, pharynx, digestive system, respiratory system, skin (including melanoma), mesothelium, soft tissues, breast, urinary tract, lymphatic and hematopoietic tissues, as well as multiple primary tumors.Conclusion. The data obtained will allow determination of the main directions for assessing the health risks of personnel of radiation hazardous facilities and the formation of a set of measures aimed at improving the system of protection and improving the health of workers at radiation hazardous enterprises and the extension of their working longevity.

Experience in the treatment of primary malignant tumors (retinoblastoma and osteosarcoma): analysis of the clinical case

Background. Retinoblastoma is a malignant intraocular tumor developing from the retinal neuroectoderm and diagnosed primarily in young children. This type of cancer is associated with a high risk of multiple primary tumors emerging after treatment completion. Multiple primary tumors are two or more independent tumors developing in one patient. Treatment of this disease is challenging.Objective – to evaluate the impact of risk factors on the efficacy of therapy for multiple primary tumors and to analyze treatment outcomes.Materials and methods. A 2-year-old boy was diagnosed with bilateral retinoblastoma (OD – stage T3bN0M0 and OS – stage T3cN0M0). He received special treatment from September 2005 to November 2006. In 2012, the patient underwent cataract surgery: the lens was removed, then an intraocular lens was installed, and laser dissection of the posterior capsule of the lens was performed. Six years later, in August 2018, the patient was diagnosed with osteosarcoma. The boy received combination organ-sparing therapy according to the EURAMOS-1 treatment protocol for osteosarcoma. During therapy, he developed a secondary tumor, namely osteoblastic osteosarcoma. Both the boy and his father were found to have a mutation in the RB1 gene.Results. Currently, patient’s condition is satisfactory; he has no complains. The boy is in remission for 2 years.Conclusion. The development of secondary tumors depends on the genetic factors, type of treatment for primary tumor, and environmental factors. Therefore, it is extremely important to assess risk factors for multiple primary tumors at the moment of primary retinoblastoma detection. The results of such assessment will help to choose an optimal treatment strategy.

Bilateral symmetric Merkel cell carcinomas of the dorsal hands: multiple primary tumors or early metastasis?

<p>Merkel cell carcinoma (MCC) is an aggressive and uncommon neuroendocrine tumor which clinically presents as a rapidly growing solitary nodule or plaque located in sun exposed areas on the head, neck, and extremities. Merkel cell carcinomas can be UV-induced or result from viral infection with the Merkel cell polyomavirus (MCV). We present a unique case of bilateral symmetric Merkel cell carcinomas located on the dorsal hands and briefly discuss options for genomic investigation to delineate if the tumors are multiple primary tumors or result of metastatic disease.</p>

Multiple Warthin Tumors With Epithelial–Myoepithelial Carcinoma of the Ipsilateral Parotid Gland: A Case Report

Multiple primary tumors of the parotid gland refer to the occurrence of 2 or more primary tumors in the ipsilateral or bilateral parotid gland metachronously or synchronously, which do not originate from postoperative recurrence or metastasis. Multiple primary tumors of the parotid gland, especially synchronous benign and malignant tumors, are extremely uncommon. A rare case of multiple Warthin tumors with epithelial–myoepithelial carcinoma of the ipsilateral parotid gland is reported as follows.

Synchronous multiple primary tumors (neuroblastoma and parathyroid adenoma) in a child: case report and literature review

The article presents a clinical case of simultaneous multiple primary tumors (the left adrenal neuroblastoma and the right lower parathyroid adenoma) in the child 11 years old.The literature describes several cases of primarily multiple tumors, one of which was neurogenic, requiring an individual approach to treatment. The relationship between the occurrence of polyneoplasia and genetic mutations is discussed.

Case Report: Novel RPGRIP1L Gene Mutations Identified by Whole Exome Sequencing in a Patient With Multiple Primary Tumors

A 78 years old Chinese woman with five different cancer types and a family history of malignancy was the subject of this study. Pancreatic adenocarcinoma and gingival squamous cell carcinoma tissues were obtained from the patient and sequenced using Whole Exome Sequencing. Whole exome sequencing identified 20 mutation sites in six candidate genes. Sanger Sequencing was used for further validation. The results verified six mutations in three genes, OBSCN, TTN, and RPGRIP1L, in at least one cancer type. Immunohistochemistry was used to verify protein expression. mRNA expression analysis using The Cancer Genome Atlas database revealed that RPGRIP1L was highly expressed in several cancer types, especially in pancreatic adenocarcinoma, and correlated with patient survival and sensitivity to paclitaxel, probably through the TGF-β signaling pathway. The newly identified somatic mutations in RPGRIP1L might contribute to pathogenesis in the patients. Protein conformation simulation demonstrated that the alterations had caused the binding pocket at position 708 to change from concave to convex, which could restrict contraction and extension, and interfere with the physiological function of the protein. Further studies are required to determine the implication of RPGRIP1L in this family and in multiple primary tumors.