ABSTRACT
Examination and assessment of target organ toxicity in toxicologic pathology of preclinical safety evaluation of drugs should combine the results of the gross pathology,histopathology and clinical pathology examination data in a well-considered,stepwise approach.In addition,the nomenclature and diagnostic criteria recommended by INHAND should be used to avoid subjective and inappropriate diagnosis.In this paper,we briefly introduced the basic principles for the examination of organ toxicity in toxicology studies,gross pathology,histopathology,diagnostic approach,procedures,and considerations,international harmonization of diagnostic term and criteria,clinical pathology parameters analysis,results of a well-concerted combination of anatomical and clinical pathology data so as to provide some reference for the examination and assessment of target organ toxicity in toxicologic pathology in the field ofpreclinical safety evaluation of drugs in China.
ABSTRACT
Toxicologic pathology plays an important role in the safety evaluation of drugs.The results of toxicologic pathology can answer the basic problems of pathological lesions such as location,severity grading,nature and prognosis,etc.Necropsy and gross pathology examination are important aspects of toxicologic pathology assessment.Procedures typically include preparation for the necropsy,euthanasia procedures,identification and recording all gross lesions,collection of tissues listed in the study protocol,determination of organ weight,as well as tissue fixation so as to be ready for the subsequent tissue processing and histopathology examination.All the procedures must be done in a consistent manner and in accordance with standard operating procedures (SOPs).The present paper briefly introduced the principles of necropsy and gross pathology examination for toxicologic pathology in order to standardize the procedures and to lay foundation for the improvement of the histopathology examination in the field of preclinical safety evaluation of drugs of China.
ABSTRACT
OBJECTIVE: To observe the diagnostic capacity and its influencing factors in the toxicologic pathology diagnostic laboratories in China. METHODS: Inter-laboratory comparison of toxicologic pathology diagnosis was cosponsored by Chinese Society of Toxicology-Toxicologic Pathology Specialty Section and Guangdong Province Hospital for Occupational Disease Prevention and Treatment. Nine digital slices of digestive system lesions were screened as comparison samples,and the reference institution with toxicologic pathology diagnostic laboratories completed the diagnosis within the prescribed time. According to the three grades of “excellent”,“satisfaction”and “dissatisfaction”,the evaluation was carried out.RESULTS: A total of 74 reference institution participated in this comparison,which distributed in 20 provinces and 4 municipalities and 156 pathologists. The reference institutions were mainly distributed in North China,Southern China and East China. There was an average of 2 pathologists per laboratory,and in the quantity of academic title,the junior,intermediate,and senior was 15,70 and 46 persons respectively. Parasitic hepatocyte cysts( 97. 3%),adenocarcinoma of small intestine( 95. 9%) and polyarteritis nodosa of the pancreas( 89. 2%) had the highest rate of “excellent”grade,while the duodenal gland inflammation( 67. 6%),foam cell aggregation in colonic propria( 40. 5%) and hepatoma adenoma( 32. 4%) had the highest rate of dissatisfaction grade in the evaluation of single case. In the overall evaluation,reference laboratories reached the “excellent”grade and the “satisfaction”grade were 78. 4% and 21. 6% respectively.The number of pathologists provided by each reference laboratory had impacts on the overall evaluation level and the single case evaluation( neoplastic lesions) in the evaluation of single case( P < 0. 05). The types of the reference laboratory,the regional distribution and the grade of the academic title had no effect on the diagnostic ability( P > 0. 05). CONCLUSION: The reference laboratory is superior in diagnosing the digestive system lesions in the inter-laboratory comparison activity.The number of pathologists in the reference laboratory is one of the influencing factors of its diagnostic ability.