Cryopreserved Thyroid Tissue Autotransplant in Pediatric Age Patients: A Feasibility Study and Literature Review

Abstract

Background and aims: This paper aims to study an alternative solution to hormonal replacement therapy in specific groups of patients who underwent thyroidectomy during childhood or adulthood. After cryopreservation, thyroid autotransplantation could be an alternative solution which would allow us to use the ability of the thyroid tissue of producing hormones according to the physiological needs of the body.

Materials and methods: A feasibility study about the effects of the most modern cryopreservation techniques on the structural and functional integrity of the follicular cells of the thyroid tissue has been carried out. Patients who could benefit from the treatment have been found for both autotransplant techniques. Additionally, a literature review has been conducted.

Results: The histological analysis has shown that cryopreservation does not alter the original architecture, and the culture examination that cell viability is successfully preserved. Moreover, both thyroid autotransplantation studies on animals and those on humans that were found in the literature have shown good results regarding the viability and functionality of the transplant.

Conclusions: The viability of cryopreserved thyroid tissue found in this study is encouraging. Further studies to evaluate the levels of FT3, FT4 and thyroglobulin in thyroid tissue after cryopreservation are needed to verify that the secretory properties of the thyrocytes have been maintained intact. Furthermore, autotransplanted cases found in the literature do not have a long-term follow-up.

Keywords: autotransplant; children; cryopreservation; thyroid.

Figure 1

Animal studies divided by year and country of publication [1,9,18,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45].

Figure 2

Human studies divided by year and country of publication [1,2,3,15,16,17,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66].

Figure 3

Histological photos of CASE1. Hematoxylin–Eosin staining. Focal regressive micro-macrofollicular aspect (* subfigure (A)) focal regressive changes (^ subfigure (B)) edema (* subfigure (C)) and dislocation of the epithelial cells (* subfigure (D)) are shown. Bar (A–C): 100 µm; (D): 20 µm.

Figure 4

Histological photo of CASE 9 showing minimal and focal edema (*). Hematoxylin–Eosin staining. Bar 50 µm.

Figure 5

Cell culture photo of CASE 1. The black shadow is the sample. The thyrocytes in the culture grow by expanding from the sample into the medium. Bar 20 µm.

Figure 6

Geographical distribution map of publications on thyroid autotransplantation in animals.

Figure 7

Geographical distribution map of publications on thyroid autotransplantation in humans.

Figure 8

Indications for autotransplantation.