A hemangioma originates from the mesodermal vascular endothelial cells. It undergoes rapid growth between one and three months after birth (3,4), and can reach 80% of its final volume at the age of three months (5). Hemangiomas rarely occur in the thyroid gland. Furthermore, they are mainly reported in adults and are rare in children. To the best of our knowledge, till 2019, only three cases have been reported in children (6–8, Table 1). Frequent secondary venous stones in the lesion can lead to a stiffer texture, and imaging occasionally reveals clusters of strong echo or calcification. Hemangiomas are easily confused with malignant tumors. Even among experienced surgical experts, the preoperative diagnosis of thyroid hemangioma is quite difficult (2). Fine needle puncture has a high risk of bleeding, and the final diagnosis in almost all patients depends upon a histopathological examination. Hemangioma is histologically classified as cavernous, capillary, synovial, venous, and so on. In case of thyroid hemangiomas, the cavernous type is the most commonly reported, while the capillary type is very rare. We present the first reported case of infantile capillary thyroid hemangioma with a review of literature.
Often, thyroid hemangioma patients do not present with any specific clinical characteristics; sometimes, only a well-defined capsulate mass or growing mass is observed. In the present case, the main manifestation was airway obstruction without palpated mass and an absence of erythema on the neck skin. The mass was detected by CT and ultrasound examination. However, it is often difficult to distinguish such masses from malignant tumors using such preoperative imaging modalities. The diagnosis of capillary hemangioma was confirmed by surgical resection and pathological examination. A review of previous literature revealed only three pediatric cases of thyroid hemangioma. The children were aged between three months and 12 years (6–8); one was an infant who had dyspnea and was placed on mechanical ventilation. Due to unstable vital signs, a pathological examination was not performed in this infant. Instead, the physicians relied on ultrasound, CT, and bronchoscopy for clinical diagnosis; the patient recovered after an empirical treatment with propranolol (8). In case of the other two patients, no symptoms were reported and thyroid hemangioma was detected by routine medical examination (Table 1).
Table 1
Case reports of thyroid hemangioma.
Study, year | Age | Sex | Location | size(cm) | Symptoms | Diagnosis method/Histology | Treatment | Prognosis |
Li Quanjiang, et al. [8] , 2019 | 12Y | F | Right | 2.0 × 1.0 | none | Pathology | NM- | NM |
Jacobson D, et al. [9] , 2014 | 3M | F | Right | 3.1 × 3.7 × 2.2 | dyspnea | Clinical diagnosis | propranolol | improve |
Okuno, et al.[8], 1981 | 7Y | M | Diffuse | NM | none | Pathology/Capillary | NM - | NM |
Ishida, et al. [7],1982 | 4Y | M | Isthmus | 1.8 × 0.9 × 0.3 | none | Pathology/Cavernous | NM - | NM |
Our case | 2M | F | Both sides | 3.0 × 3.0 × 1.0 | dyspnea | Pathology/ Capillary | Operation and propranolol | improve |
Y year, M month, F femal, R right NM not mention |
Because most infantile hemangiomas tend to regress spontaneously, active treatment is not recommended. Treatment is only required for complicated cases, which include life-threatening infantile hemangiomas (obstructive subglottic and bleeding gastrointestinal tumors, large hemangiomas causing cardiac insufficiency, and so on), infantile hemangiomas causing functional impairment (periocular hemangiomas causing amblyopia, obstructive tumors of the external auditory channel or the nose, and ulcerated infantile hemangioma), and infantile hemangiomas likely to cause disfigurement (large facial tumors, large infantile hemangiomas in the perimammary region in girls, and so on). Infantile hemangiomas that manifest as an obstruction require immediate therapy, such as in the present case. Treatment includes topical or intra lesional injections, surgical resection, oral drugs, and so on. Oral propranolol is the drug of first choice at a dose of 2–3 mg/kg per day, it should be administered as early as possible to avoid potential complications. Treatment is continued for at least six months and is often maintained until 12 months of age (occasionally longer) (3,9).Due to difficulties in preoperative diagnosis, most thyroid hemangiomas are only diagnosed by a postoperative histological examination. Therefore, surgical removal of thyroid hemangiomas is recommended. However, this carries a high risk, because hemangiomas are prone to hemorrhaging during operation; around 2000 ml of blood loss is reported in adults (10).Thus, it is important to maintain the integrity of the capsule, which can significantly reduce the risk of hemorrhaging and avoid a residual relapse. In our case, the nature of the mass was unclear before the operation, and its blood supply was rich. Fine needle aspiration could not provide enough tissue for pathological biopsy and carried a risk of bleeding. Therefore, this situation met the indication for operation and we performed a surgical treatment. The nature of the tumor was determined intraoperatively by a frozen pathological biopsy. Only the left lesion was removed, and the right side of the thyroid was preserved. Propranolol was administered after the surgery. Regular follow-up revealed that the hemangioma decreased in size. This indicated that surgical resection, combined with oral propranolol, may reduce hemorrhage risk and postoperative complications of thyroid hemangioma in infants; however, more studies are needed to confirm this.
To the best of our knowledge, this is the first reported case of a capillary thyroid hemangioma in an infant. In conclusion, when a well-defined capsulated mass is detected on the medical image, the possibility of primary thyroid hemangioma, in addition to that of a tumor, must be considered. The final diagnosis depends on a histopathological examination. When the tumor presses on the trachea and produces corresponding symptoms; it is an indication of surgical treatment. Although preoperative diagnosis is difficult, the prognosis after surgery is good. Surgical resection, combined with oral propranolol, reduces the surgical risk and postoperative complications of thyroid hemangioma in infants.