Application Of Cell Wax Block Technique In The Diagnosis Of Pleural Effusion

Purpose:Pleural effusion is one of the most easily complicated clinical manifestations in patients with advanced non-small cell lung cancer(Non-small cell lung cancer,NSCLC),the role of molecular targeted therapy in the treatment of advanced NSCLC is becoming increasingly prominent,Experts consensus of 2013 pointed out that:for patients with NSCLC,it is advised to detect EGFR mutation,ALK and ROS-1 gene fusion.But due to physical condition,economic problems,the willingness of patients and their families and other reasons,some patients with advanced lung cancer can not obtain tissue pathology,thus influence the diagnosis of disease and molecular classification,then the cell pathological specimens,especially in the pleural effusion can some or all replace tissue specimens,to make a judgment of the diagnosis of disease,histologic typing of malignant tumor and further molecular typing,and guide the treatment.However,the traditional cytology smear technique generally has overlapping cell accumulation,background staining is deep and not easy to observe,Samples can not be long-term preservation,etc,Pleural effusion is often taken to make the centrifugal sediment into a cell wax block,to make slice HE dyeing,immunohistochemical staining,may cover the shortage of conventional smear examination.In this study,pleural effusion was collected to make cell wax block,compared with the conventional pleural effusion cytospin,to explore the role of cell wax block technique in the diagnosis of pleural effusion,and to provide a new feasible way to make EGFR,ALK gene detection for those lung cancer patients who unable to obtain tissue specimens.Methods:A total of 54 patients with pleural effusion were collected from the fourth hospital of Hebei Medical University(East Hospital District)from June 2015 to February 2016,The patients' gender,age,pleural effusion location,color,transparency and nature were recorded.All cases were performed with routine cell smear HE staining(conventional group),over the same period,cell wax blocks are maded to slice HE dyeing(cell wax block group),to compare the cell number,morphology,staining background and so on between the conventional group and the cell wax block group,and the consistency of the results of the two methods are compared.Preparation procedure of cell wax block:Collect:Taking fresh pleural effusion about 250 ml,to static 30 min in room temperature;Centrifugate:to discard supernatant,leaving the bottom liquid about 120 ml,evenly placed in 12 test tube in the centrifugal,2000 r / min,10 min,(If the amount of precipitation is less,can be re-centrifugal or repeated);Fixed:Discard the supernatant with Straw will precipitate out,into the prepared clean glass bottle,adding 10% neutral buffered formalin fixed 10 times the amount of precipitate,with a straw to blow the sediment gently,in order to fully fixed,static,fixed 12h;Dehydrate:The supernatant was discarded and the cell sediment was poured into the mirror paper which was folded into a funnel shape,with absorbent paper to absorb excess liquid,the lens paper wrapped into the 70% alcohol in the night,dehydration 12 h,with tweezers to remove,placed in absorbent paper to suck,Respectively,in 80%,95%,100% alcohol concentration gradient dehydration each 1 hours;Inspect:after dehydration package cell block of paper into the package with a new 10% neutral buffered Faure Ma Lin fixed liquid small glass bottle to send to pathology department.statistical method:All the data were processed by the SPSS13.0 version of statistical software.Results: 1 Clinical characteristics of the objectAmong all the 54 patients enrolled,there are 31 cases of male patients,accounting for 57.4%,23 cases of female patients,accounting for 42.6%;The age distribution is in the range of 31-82 years old,the average age is 63.0 ± 11.3 years.30 cases are at the age <65 years old,accounting for 55.6%,24 patients ?65 years old,accounting for 44.4%;Bloody pleural effusion in 12 cases,accounting for 22.2%,non bloody pleural effusion in 42 cases,accounting for 77.8%;opacity pleural effusion in 44 cases,accounting for 81.5%,transparent pleural effusion in 10 cases,accounting for 18.5%;26 cases of left pleural effusion,accounting for 48.1%,right pleural product liquid in 28 cases,accounting for 51.9%;49 cases of exudative pleural effusion,accounting for 90.7%,transudative pleural effusion in 1 cases,accounted for 1.9%,there are 4 cases between the two,accounting for 7.4%.2 Success rate of cell wax block makingA total of 54 cases of pleural effusion were collected,of which 44 cases were successfully made into cell wax blocks,and the success rate was 81.5%(44/54).3 The characteristics and interpretation results of conventional group and cell wax block group 3.1 Microscopic Appearance(see figure 1-10,conventional group:figure1-8 cell wax block: figure9-10)The conventional group showed that thickness of smear uneven staining of strong background,cells stacked,unclear structure.Cell wax block group showed: background staining clean,staining clear contrast,enrichment of cell number,uniform thickness and in most cases can observed cell arrangement and organization structure.3.2 Interpretation results 3.2.1 The diagnosis of 16 cases which cell block group did not find cancer cellsIn the 44 specimens which were prepared into cell wax blocks successfully,these 33 cases,there were 28 cases of cancer cells found in the cell wax block group,no cancer cells were found in 5 cases,In the other 11 cases,suspicious cancer cells were found in the conventional group in 1case,abnormal cell in 3 cases,In the cell block,2 cases showed no tumor cells,2 cases showed a little degeneration of cells,1 cases of pleural effusion of unknown etiology.There were 3 cases did not found cancer cells in 3 cases both in conventional group and cell wax block group,histopathological diagnosis of small cell carcinoma.There were 3 cases of conventional group and cell wax block group were visible lymphocytes,plasma cells and other components,no tumor cells,the clinical diagnosis is tuberculous pleurisy.Cancer cells were found the other 5 cases in the conventional group,cell wax block group was negative.3.2.2 The comparison of detection rate of malignant pleural effusion in conventional group and cell wax block groupIn the 44 specimens which were prepared into cell wax blocks successfully,In the conventional group,33 cases were diagnosed as malignant pleural effusion,11 cases do not found cancer cells;In the cell wax block group,there were 28 cases were diagnosed as malignant pleural effusion,16 cases do not found cancer cells.The sensitivity of cell wax block technique in the diagnosis of malignant pleural effusion was 84.8%,specificity was 100%,the diagnostic concordance rate was 88.6%.Two groups of patients with malignant pleural effusion were detected,using the Fisher exact probability method of four case table data,P>0.05,the results were not statistically significant,it can be considered that the conventional group and the cell wax block group for the same detection rate of malignant pleural effusion.In this experiment,1 case was diagnosed with lung adenocarcinoma and of which pleural effusion cell block underwent D5F3 immunohistochemical test results(+ + +).Conclusion:1 In the 54 cases of pleural effusion,there were 44 cases successfully made into cell wax block,and the success rate was 81.5%,this method is simple and feasible,and it is convenient for clinical application.2 The diagnosis consistency of malignant pleural effusion was good in the cell wax block group and the conventional group,the results showed that the cell wax block technique can replace the conventional pleural effusion smear examination,as an alternative method for the diagnosis of pleural effusion.3 Microscope observation showed that,In the cell block sections we can see more cells,and they distribut uniformly,the dyeing background and cell morphology is clearly,and to keep some of the organizational structure,which is conducive to diagnosis.4 The pleural effusion was made into cell wax block,play a role in aggregating cells,equivalent to the tissue block,can be long-term preserved,serial sections,to facilitate the special staining and gene detection,etc.