Toluidine blue for the detection of sentinel lymph nodes in patients with thyroid cancer

Abstract

Introduction Thyroid cancer (TC) demonstrates steady growth in incidence worldwide and remains an urgent problem in oncology. The detection of sentinel lymph nodes (SLN) with a selective dye and further histological examination in selecting the proper (personalized) surgical strategy and the volume of surgical intervention for clinically undetermined regional lymph nodes. The purpose of the study is to evaluate the effectiveness and safety of intraoperative detection of SLN with a 1% toluidine blue aqueous solution. Material and methods The significant tasks are to identify the pattern of TC metastases to cervical lymph nodes, to establish the prevalence of “skip” metastases, to compare the frequency of complications after total thyroidectomy and central neck dissection and lateral neck dissection with total thyroidectomy and central neck dissection, and to determine the feasibility of the application of lateral neck dissections in patients with papillary and follicular TC without metastases to regional lymph nodes (according to physical examination and ultrasound). Results According to our data the SLN identification rate was 97.6%. Sensitivity, specificity, positive predictive value, negative predictive value, and frequency of false negative and false positive results was 89.2, 94.6, 88.03, 95.16, 10.8, and 5.4%, respectively. The most common metastasis was in the central neck compartment (83.7%). Skip metastases were determined in 4.9% of patients. Conclusions The low prevalence of “skip” metastases and a significant risk of postoperative complications (wound exudation, lymphorrhagia, inflammation, hypoparathyroidism, paresis of the vocal cords) support the idea that lateral neck dissection is appropriate only in cases of confirmed metastases by physical examination and/or ultrasound at the preoperative stage.

Metastatic Ovarian Cancer: Bibliographic Analysis

“…This environment is mediated by immune suppression, angiogenesis, tumor-associated fibroblasts (CAFs), and macrophages, thereby promoting remodeling of the ovarian tissue stroma. CAFs are reprogrammed stromal cells that directly influence tumor initiation and progression, remodeling of the extracellular matrix, and metastasis [23,24]. Ovarian tumor cells are known to be able to convert adipose mesenchymal stem cells into CAFs by overexpressing α-smooth muscle actin.…”

Sentinel lymph node mapping: current applications and future perspectives in thyroid carcinoma

“…In Wang et al ( 66 ) described the use of indocyanine green (ICG) with methylene blue for detecting SLN in 45 micro-PTC patients with a longer operative time but a lower rate of hypoparathyroidism: the authors concluded that for SLN in TC ICG in combination with methylene blue is feasible, safe and also clinically significant for protection of the parathyroids. In Moskalenko et al ( 24 ) evaluated the effectiveness and safety of intraoperative SLN detection in 187 patients using for the first time a 1% toluidine blue aqueous solution, and with a DR of 97.6% they found it to be no less accurate that other blue dyes.…”

“…With the VD method at surgery, the vital blue dye intra- or peri-tumoral injection is performed generally utilizing a tuberculin syringe ( 24 , 62 , 64–67 ). The authors recommend not mobilizing the thyroid before injection to ensure intact lymphatic drainage.…”

“…After dissection, the SLNs are submitted to histopathology for frozen section analysis. The main limits of the VD procedure include: 1) the potential disruption of the lymphatics draining the tumor, 2) the difficult identification of the SLNs located outside the central compartment, 3) the risk of removing blue stained parathyroid glands, and 4) the procedure is laborious requiring experience ( 24 , 62 , 64–69 ).…”