Cytology, also known as clinical cytology and tumor cytology, is correctly called cytopathology, which is the same as pathological diagnosis for qualitative diagnosis of tumors. Cytology is simple, painless, inexpensive and accurate, and can be used for preoperative diagnosis and guiding treatment. According to the different tumor sites, it can be divided into: 1. Fine needle aspiration cytology for surface masses The masses occurring on the skin, lymph nodes, breast, thyroid, oral cavity, subcutaneous muscle, fat and cartilage can be aspirated by fine needle aspiration and smear for examination and diagnosis, and in case of cystic lesions, the fluid can be extracted and injected with drugs to play a therapeutic role. 2.Exfoliative cytological examination of cavity organ masses The cavity organs generally have an opening to the outside world, such as nasopharynx, larynx, trachea, lung, esophagus, stomach, intestine, kidney, bladder, uterus, vagina, etc. The cellular components or secretions shed can be examined by exfoliative cytology, such as sputum smear, cervical smear, urine smear to find cancer cells. The above organs can also be examined by endoscopy, such as gastroscopy, enteroscopy, bronchoscopy, cystoscopy, etc., and biopsy smear can be taken for cytological examination, which is also called endoscopic brush or print cytological examination. 3.Puncture cytology of deep organ masses liver, pancreas, spleen, ovaries, prostate, bone and other organs, due to the deep location, not easy to touch, not easy to extract cellular components, so more use of ultrasound or CT guidance with a special puncture needle, aspirate the cellular components of the mass smear, sometimes can bring out the tissue block for pathological examination, such as lung puncture of lung occupancy, liver, pancreas, prostate and bone puncture cytology examination . Intraoperative rapid cytological examination of organ masses can also be performed by puncture and print during surgery. 4.Print cytology is to use biopsy excision, surgical biopsy and endoscopic biopsy to print the tissue directly on the slide, which has both cytological characteristics and histological structure, and can determine both benign and malignant, and can determine the origin of the tissue, which not only improves the positive rate, but also reduces the false negative and misdiagnosis rate, which is better than other cytological examinations, and is most suitable for rapid intraoperative pathology. Diagnosis.