Comment on the results of the method of visualization and sentinel lymph node biopsy in thyroid carcinoma by Methylene blue in Hanoi Medical University Hospital from 11/2014 to 9/2018 and analyze the some factors affecting the results of method. Evaluate the value of sentinel lymph node biopsy in the diagnosis of occult cervical lymph node metastasis.
MINISTRY OF EDUCATION MINISTRY OF HEALTH HANOI MEDICAL UNIVERSITY NGUYEN XUAN HAU RESEARCH THE VALUE OF SENTINEL LYMPH NODE BIOPSY IN THYROID CARCINOMA Specialization :Oncology Code : 62720149 SUMMARY OF DOCTORAL DISSERTATION HANOI - 2019 THIS STUDY WAS COMPLETED IN: HANOI MEDICAL UNIVERSITY Spervisor: Assoc Prof MD Le Van Quang Reviewer 1:Assoc Prof MD Le Ngoc Ha Reviewer 2:Assoc Prof MD Ngo Thanh Tung Reviewer 3:Assoc Prof MD Le Trung Tho The thesis will be defended before the Examining Board at university level in Hanoi Medical University At …… o’clock……… Date …… Month …… Year… This thesis could be found at - National Library - Centre Medical Information Library LIST OF PUBLICATION RELATED TO THE DISSERTATION Nguyen Xuan Hau, Tran Thi Hau, Le Thi Hang (2017) Clinical, subclinical characteristics and histopathology of early thyroid cancer at Hanoi Medical University Hospital Vietnam Medical Journal, Number 1, volume 456 Nguyen Xuan Hau, Le Van Quang, Duong Chi Thanh (2017) The result of visualization of sentinel lymph node biopsy with Methylene Blue in thyroid carcinoma Vietnam Medical Journal, Number 2, volume 456 Nguyen Xuan Hau and Le Van Quang (2018) The role of sentinel lymph node biopsy in thyroid carcinoma and the factors affecting the value of the method Vietnam Medical Journal, Number 2, volume 472 Le Van Quang, Nguyen Van Hieu, Nguyen Xuan Hau, Nguyen Van Hung (2018) Role of sentinel lymph node biopsy in papillary thyroid carcinoma in Vietnam International Journal of Hematology and Oncology, number 4, Volume 28 INTRODUCTION Reason to choose the thesis Thyroid cancer is the most common disease in endocrine cancer, accounting for 3.6% of all cancers in general Surgery is the most important treatment in thyroid cancer Thyroidectomy plus lymphadenectomy increase the rate of complications after surgery, but the disease recurrent mainly in cervical lymph node and lymphadenectomy is the first priority choice Surgery to remove central lymph node in recurrent thyroid cancer increase the risk of complications such as paralysis of the recurrent laryngeal nerve and hypoparathyroidism To limit systemic cervical lymph node dissection, finding a method to detect occult lymph node metastasis is necessary to determine the treatment strategy Sentinel lymph node is defined as the first lymph node in the lymphatic drainage area to be drained from the primary tumor, which reflects the condition of the remaining lymph nodes with or without lymph node This result contributes to the detection of metastatic lymph nodes that are smaller than 2-3 mm in diameter difficult to detect by other techniques such as high resolution ultrasound In the world, there have been many studies on the sentinel lymph node of thyroid cancer, however, there has not been any research in this field in Vietnam Therefore, we carried out the thesis: "Research on the value of sentinel lymph node biopsy in thyroid cancer" with the following two objectives: Comment on the results of the method of visualization and sentinel lymph node biopsy in thyroid carcinoma by Methylene blue in Hanoi Medical University Hospital from 11/2014 to 9/2018 and analyze the some factors affecting the results of method Evaluate the value of sentinel lymph node biopsy in the diagnosis of occult cervical lymph node metastasis New finding of the thesis: - This is the first study in Vietnam, using Methylene Blue to detect sentinel lymph node in thyroid cancer, to help determine the exact occult lymph node metastasis, thereby giving a strategy the cervical lymph node dissection with the same time reasonable thyroidectomy - The rate of sentinel lymph node detection with Methylene Blue is very high: 98.2%; Most lymph nodes are in the pre-tracheal group (group 6): 90.4% - Percentage of non-metastatic lymph nodes on pathology: 55.7%; metastasis on pathology: 44.3%, the rate of occult cervical lymph node metastasis is very high: 51.5% - Sensitivity, specificity, positive predictive value, negative predictive value, overall accuracy and false negative rate of the method are: 86%, 100%, 100%, 87,1%, 92.8% and 14% respectively The structure of the thesis: The thesis conclude 122 pages, with main chapters: Introduction pages, Chapter (Overview) 40 pages, Chapter (Subjects and Research Methods) 18 pages, Chapter (Research results) 29 pages , Chapter (Discussion) 30 pages, Conclusion and Recommendations pages The thesis has 33 tables, pictures and charts, 155 references (26 Vietnamese references, 129 English references) Chapter 1: OVERVIEW 1.1 Introduction Sentinel lymph node is defined as the first lymph node in the lymph nodes receiving lymph nodes from primary tumors Since the past 19 years, approved sentinel lymph node biopsy is a technique to determine the metastatic presence of melanoma cancer and early breast cancer Recently, sentinel lymph node biopsy has been proposed for use in other cancers, including thyroid cancer The role of this method is being clarified by the authors The results of lymph node biopsy help the surgeon make a decision right away in terms of regional lymphadenopathy and appropriate management or systemic behavior 1.2 Sentinel lymph node biopsy in thyroid carcinoma 1.2.1 Technology Blue dye is an injection used most often with methylene blue, isosulphan blue This method involves injecting a blue indicator into sites with the same lymphatic drainage system with the tumor then a certain period of time will be performed to detect lymph nodes by direct observation of the pathways Blue lymphatic drainage leads to lymph node All blue dyes disappear during the process of making the specimen and not affect histological analysis About radioisotopes, different forms of 99m-Technetium The lymph nodes in these cases are detected by skin markers for lymph nodes or it can be detected by radioactive signals using a gamma probe during surgery After exposition of the thyroid gland, four quadrants around the tumor were injected with a total of 1ml of methylene blue with tuberculosis syringe At this time, stop the operation for one minute to allow diffused dye The lymphatic pathways catch a blue stain (the stain of the blue dye, then continue into the central cavity and the blue stain nodes are taken and sent to frozen section 1.2.2 Factors affecting the results of the method Although the studies have shown that the rate of visualization of the sentinel lymph node with Methylene blue is very high, there is still a small proportion of not showing the lymph nodes when perform the method To explain the absence of this sentinel lymph node, many studies suggest that the lymph node system from the tumor to the lymph node is disrupt during the process of thyroid disclosure, the lymphatic pathway is blocked by invasive tumors or The main lymphatic vessels that were not detected after injecting the color indicator may be that it is behind the esophagus or after the thyroid site When studying other factors affecting the results of sentinel lymph node such as age, sex, tumor position in lobe, tumor size, tumor stage, multifocality, all studies showed that there was no the relationship between the above factors with the result of the sentinel lymph node Chapter 2: OBJECTIVES AND METHODOLOGY 2.1 Research subjects The patient was diagnosed with thyroid cancer and surgery at the Oncology-Palliative Care Department, Hanoi Medical University Hospital from November 2014 to September 2018 2.1.1 Sample size Sample size is determined by the formula: p(1 – p) n = Z21-α/2 (pε)2 Where n: Minimum sample size in the study Z1-α/2: coefficient of confidence with a probability of 95% ( ε= 0.05) → Z = 1.96 Select ε: deviation of p, limit of 10% (ε = 0.1) p: percentage of lymph nodes without metastasis (p = 0.7) according to Cabrera's study (2014) From the above formula, we selected 170 patients 2.1.2 Criteria for selecting research subjects - Patients diagnosed with thyroid cancer based on clinical, ultrasound and cytology Cases of unknown cancer in cytology and / or ultrasound will be frozen section in surgery - Diagnosis of clinical stage T1,2,3,4; N0; M0 classified by AJCC 2010 - Injection of methylene blue around the tumor - Surgical removal of selective lymph nodes group VI and group II, III, VI on both sides - Results of postoperative pathology are differentiated thyroid carcinoma 2.1.3 Exclusion criteria - Metastatic lymphoma of the lymph nodes clearly clinical, distant metastasis - There is a history of allergy to Methylene blue - Thyrois cancer is not the epithelial cell type - Patient was undergoing thyroid surgery at the other hospital - Patients disagree to participate in the study 2.2 Research Methods 2.2.1 Research design Descriptive research study 2.2.2 Research Methods 2.2.2.1 Exploiting clinical and subclinical information 2.2.2.2.Technical process of visualization and sentinel lymph node biopsy In this study, we used the method of sentinel lymph node biopsy with Methylene Blue - The patient is in the supine position, his hands pressed close to his body, neck up to the maximum, pillows placed under the shoulders to increase the ability of the neck - Endotracheal anesthesia, antiseptic neck area down through depressions, above the chin - Incision skin across the lower neckline, about two fingers away from the noch of breastbone, cutting the platisma muscle, dissection the two skin flaps up and down Open along the neck fascia before the trachea, clearly showing the thyroid lobe containing the tumor - Find and protection the parathyroid glands and recurrent laryngeal nerves before injecting Methylene Blue, avoiding difficulties in finding later - Inject ml of Methylene Blue into positions around the tumor: hours, hours, hours and 12 hours Be careful not to let Methylen around the operation space to avoid confusion when making a judgment If gauze and gloves are slotted with a color indicator, they must be replaced to avoid penetrating the surrounding organization - Gently massage the thyroid lobe that is injected within minute with the fingertip Dissection around the thyroid lobe to detect blue lymphatic drainage This process should be carried out gently, meticulously, hemostatic to facilitate maximum observation Follow all the detected lymphatic pathways to the stain lymph nodes (lymph nodes) Take all the stain lymph nodes and record the sentinel lymph node in separate groups - Duration is 10 - 15 minutes from the injection of color indicator Past that time, if the lymphatic or lymphatic channels are not detected, the procedure is classified as not recognizing the lymph node - Total thyroidectomy and neck lymphadenectomy selected at the center neck group and lateral neck group or lobe thyroidectomy plus isthmusectomy and combined with selective neck lymph nodes remove are conducted according to modern surgical standards for thyroid cancer 2.2.2.3 Evaluation parameters Sentinel lymph node biopsy result Frozen Metastasis section No metastasis Total Final pahtology Metastasis No metastasis a b Total a+b c d c+d a+c b+d a+b+ c+d - Detection rate = Number of detected cases with sentinel lymph node / total number of cases performed - Sensitivity = Number of sentinel lymph node (+) / Number of patients with lymph node metastasis on final pathology= a / (a + c) - Specificity = Number of sentinel lymph node (-) / Number of patients with no lymph node metastasis on final pathology = d / (b + d) - Total accuracy = (frozen section positive positive lymph node + true negative frozen secton) / Number of lymph nodes detected = (a + d) / (a + b + c + d) - The rate of false negative = Number of sentinel lymph node (-) / Number of patients with lymph node metastasis on final pathology = c / (a + c) 2.3 Data analysis Data were collected and statistically processed with SPSS 16.0 software according to research criteria The statistical method used includes: - Descriptive statistics: average, standard deviation - Comparison of the ratio: test χ2, statistical significance level was established when P