Malignant thyroid tumors invading the trachea often lead to large postoperative tracheal defects. Various reconstruction techniques have been described, including primary closure, end-to-end anastomosis, autologous cartilage grafts, local flaps, and free flaps. However, selecting the optimal method remains challenging for many surgeons. Among available methods, the sternocleidomastoid myoperiosteal flap, first introduced by Michael Friedman in 1968, offers several advantages. These include its relatively small volume, reliable vascularity, and sufficient stiffness, which prevents tracheal collapse and is crucial for maintaining a stable airway. Additionally, the flap can be easily performed during surgery on the cervical region, proving versatility for tracheal reconstruction [1-5]. We present a case report of successful tracheal reconstruction using a sternocleidomastoid flap in a patient with a partial tracheal defect following the surgical resection of a malignant tumor invading the trachea.

A 77-year-old woman presented with a neck mass that had been incidentally discovered approximately two months earlier. The patient had a history of hypertension, managed with medication, with no other significant medical or family history. A fine-needle aspiration biopsy performed at another hospital, prompted by nodules in the thyroid gland observed on neck ultrasound, confirmed papillary thyroid carcinoma with lymph node metastasis. The patient was subsequently referred to the Otolaryngology-Head and Neck Surgery Department at Pusan National University Hospital.

Neck magnetic resonance imaging (MRI) identified a large mass in the thyroid gland, which caused compression of the upper trachea and esophagus on the right side and resulted in upper tracheal stenosis (Fig. 1). The tracheal wall and the mass border on the right side appeared unclear, suggesting tracheal invasion. Bronchoscopy confirmed upper tracheal stenosis (Fig. 2), while esophagogastroduodenoscopy showed no esophageal invasion. Preoperative positron emission tomography-computed tomography (PET-CT) and chest CT ruled out distant metastasis.

Due to suspected tracheal invasion, tracheal resection followed by reconstruction was deemed necessary. The patient underwent total thyroidectomy, lymph node dissection, and partial tracheal resection by the Otolaryngology-Head and Neck Surgery Department. The area of tracheal invasion, which extended from the right lateral side of the cricoid cartilage to the third tracheal ring, was resected. The vocal cords and the recurrent laryngeal nerve were preserved, and intraoperative frozen section analysis confirmed negative margins.

After tumor resection, the tracheal defect measured approximately 30×20 mm from the cricoid cartilage to the third tracheal ring (Fig. 3). A plastic surgeon performed tracheal reconstruction using a sternocleidomastoid myoperiosteal flap. The flap (35×22 mm) was elevated from the right clavicle to the sternal head, including a large enough periosteum for covering the defect. The sternocleidomastoid muscle was dissected to reach the defect without tension, and vertical mattress sutures were used to inset the flap (Figs. 4, 5). In this process tension was applied to the periosteum to prevent tracheal collapse during phases of negative pressure. The patient underwent immediate extubation without significant airway problems.

Discharged on the 8th day post-surgery, the patient received follow-up care from the Otolaryngology-Head and Neck Surgery and Plastic Surgery Department. A laryngoscopy and neck CT 3 months post-surgery revealed no abnormalities, and the patient experienced no airway problems (Fig. 6).

Papillary thyroid carcinoma with tracheal invasion often necessitates total thyroidectomy with tracheal resection and lymph node dissection. The optimal oncological approach involves surgically removing the tumor and adjacent tissue with clear margins to ensure complete tumor cell removal.

The choice of reconstruction method after resecting a malignant trachea tumor depends on the defect size. For small defects, primary closure or secondary closure after tracheostomy formation may suffice [6]. Simples closure of larger defects, however, carries the risk of ischemia, stenosis, or dehiscence due to increased suture tension. End-to-end anastomosis is an option for large defects with significant invasiveness, requiring multiple staged surgeries, which can be especially challenging in cases of recurrent tumors [7]. Autologous cartilage grafting is another option for reconstruction but it poses complications such as scar formation, bleeding, and inflammatory reactions [8,9]. Reconstruction using adjacent tissue flaps, such as the sternocleidomastoid myoperiosteal flap used in this case, provides a simple, single-stage technique with sufficient stiffness and stable vascularity, preventing tracheal collapse and offering several advantages [1-5,10,11].

In this case, the tracheal defect, accounting for <50% of the tracheal circumference, extended from the cricoid cartilage’s inferior border on the right lateral side to the third tracheal ring. Primary closure was challenging due to compromised margins from an additional frozen biopsy. Therefore, reconstruction using the sternocleidomastoid myoperiosteal flap was chosen. During the elevation of the sternocleidomastoid myoperiosteal flap, the dissection was extended not only to the clavicular head but also to the sternal head. This approach minimized the dead space created during flap insetting at the tracheal defect and ensured improved neck mobility, promoting patient recovery and enhancing daily functionality. Furthermore, the patient maintained a well-preserved airway to the extent that immediate extubation could be performed after surgery. The patient was transferred to the intensive care unit for observation for one day postoperatively. Postoperative positioning involved avoiding neck extension and preventing the head from turning to the left. A nebulizer and expectorants were used until post-operative day 3. Antibiotics were administered until postoperative day 6. Initially, an L-tube was inserted for feeding, which was removed on the first postoperative day as no abnormalities were observed, and a liquid diet was initiated. The patient did not report any significant airway problems. The patient experienced no significant airway problems or complications and was discharged on postoperative day 8.

This case illustrates the successful tracheal reconstruction of a partial defect resulting from the surgical resection of papillary carcinoma invading the trachea using a sternocleidomastoid myoperiosteal flap in a single surgery. This case highlights the clinical utility of the sternocleidomastoid myoperiosteal flap for tracheal reconstruction following malignant thyroid tumor resection.