Study On The Pathological Diagnoses Of Fragmented Specimens After Endoscopic Thyroidectomy

Background and Objective: During Endoscopic Thyroidectomy (ET), the contradiction of dragging a large specimen from a small incision forces the surgeons to depress or drag the specimen really tough, or even to cut the specimen into pieces. This situation creates doubt on the credibility (real positive rate) of the pathological diagnoses after endoscopic surgery. This experiment was designed to study on the credibility of the fragmented specimens after endoscopic thyroidectomy. Furthermore, we discussed on the possible factors that influence the pathological diagnoses in this situation. Currently there has been no other reported research specifically on this issue.Method: Take the entire specimens of 40 patients who received routine open thyroidectomy in the 1st affiliated hospital of JiNan University to the Pathological test. After routine intra-operative frozen segmentation, each of the specimens was split into two halves according to certain principles that ensured the balanced situation between the two halves. One half was sent to routine Pathological test, while the other half was put into the specimen bag in the endoscopic surgical simulator, and then the process of depressing, dragging and cutting the specimen into pieces from a 10mm incision was simulated. The entire fragmented specimen was then colleted and fixed together before being sent for Pathological test. Underthe mentoring of two experienced Pathologists who knew nothing about the clinical data, the writer finished the processes of choosing the suspicious pieces and making the paraffin section of this case. Then the two Pathologists were asked to give the 1st diagnosis to this case independently.By doing this we got the 1st group of Pathological diagnoses (Group B). Then the Pathologists were told main clinical data, including chief complaint, relative case history and treatment history, main positive signs and lab results before they gave the diagnosis to the same patient again. By doing this we got the 2nd group of Pathological diagnoses (Group C). Set the routine Pathological diagnoses as the standard, we got the real positive rate of the Pathological diagnoses of fragmented specimens by comparing group B and group C to the standard diagnoses respectively. Then group B and group C was statistically analyzed with Chi-square test in order to get the degree of difference between them. Finally, we discussed relative factors that might influence the Pathological diagnoses of fragmented specimens and relative measures to optimize the process.Results: 1. By comparing the diagnoses of group B and the standard diagnoses we learnt the following facts: among all the diagnoses of doctor Alpha there were 31 matching the standard, which made out a real positive diagnostic rate as 77.5%; among all the diagnoses of doctor Betathere were 32 matching the standard, which made out a real positive diagnostic rate as 80%. There were 6 cases of which the diagnoses didn't match the standard. Among the 6 cases there were 5 cases about the differentiated diagnosis between nodular goiter and thyroidal adenoma. Missed diagnosis to one case of thyroidal minimal carcinoma (slice number 32) by both of the two doctors should be noticed specifically. 2. By comparing the diagnoses of group B-alpha and group C-alpha, we learnt the following facts: the real positive diagnostic rate of group C-alpha was improved (77.5%~82.5%), however, there was no statistical difference between the rates (P<0.05). By comparing the diagnoses of group B-beta and group C-beta we learnt the following facts: the real positive diagnostic rate of group C-beta was improved (80%--85%), however, there was no statistical difference between the rates (P>0.05 ) . Conclusion: 1. The rate of mis-diagnosis to fragmented specimens were relatively high (10-12.5%). We assume that the main reasons are: less accurate selection of specimen from fragments, and atypical features under microscope. 2. When the specimen was cut into too many small pieces, the awareness of clinical data helps increase the positive diagnostic rate of the Pathologists, and it will be of great help in the diagnosis of Pathologists, especially in diagnosing diseases such as thyroidal carcinoma and hyperthyroidism. 3. Diagnosis from intra-operational frozen section is a very important reference forPathological diagnosis after ET, and hence should be set as a routine procedure in ET.