Primary tracheal tumors are far less common than bronchial, lung, and laryngeal tumors. There are many types of primary tracheal tumors, with malignant ones being the majority. The most common is squamous cell carcinoma, followed by adenoid cystic carcinoma. Additionally, there are rare cases such as carcinoid tumors, mucoepidermoid carcinoma, carcinosarcoma, and chondrosarcoma. Primary benign tracheal tumors include hamartomas, papillomas, leiomyomas, chondromas, fibromas, and hemangiomas. Primary malignant tumors from the larynx, bronchi, lungs, thyroid, esophagus, or mediastinum can also invade the trachea, forming secondary tracheal tumors.

bubble_chart Pathological Changes

Most primary malignant tumors of the trachea grow at the junction of the cartilage rings and the membranous part. Squamous cell carcinoma may appear as a mass protruding into the tracheal lumen or ulcerate to form an ulcer. Sometimes, cancerous lesions can infiltrate a long segment of the trachea.

Advanced stage cases often involve metastasis to mediastinal lymph nodes or spread into lung tissue, and may directly invade the esophagus, recurrent laryngeal nerve, and larynx. Adenoid cystic carcinoma generally grows more slowly, with delayed onset of metastasis, sometimes presenting as long-segment submucosal infiltration or growth into the mediastinum. Some tumors are dumbbell-shaped, with a small portion protruding into the tracheal lumen and a larger portion located in the mediastinum. Advanced stage cases may invade the mediastinum and bronchi.

Primary benign tracheal tumors are diverse in type and morphology. Most tumors grow slowly, with smooth surfaces, intact mucosa, and often have pedicles, without metastasis. However, incomplete resection can lead to recurrence. Papillomas mostly occur in the membranous part of the trachea, protruding into the tracheal lumen with slender pedicles, ranging in size from a few millimeters to 2 cm. Sometimes they are multiple, with a wart-like surface, soft and fragile, prone to detachment and bleeding upon rupture.

The clinical symptoms of a tracheal tumor vary depending on the tumor's location, size, and nature. Common early symptoms include an irritating cough with little to no phlegm, sometimes accompanied by blood streaks. When the tumor grows large enough to obstruct more than 50% of the tracheal lumen, symptoms such as shortness of breath, difficulty breathing, and wheezing may occur, often misdiagnosed as bronchial asthma, leading to delayed treatment. In advanced cases of malignant tracheal tumors, symptoms may include hoarseness, difficulty swallowing, tracheoesophageal fistula, compression of mediastinal organs and tissues, cervical lymph node metastasis, and pulmonary purulent infections.

bubble_chart Diagnosis

A tracheal tomography can reveal the location and extent of the tumor as well as the degree of tracheal lumen narrowing. Tracheal iodized oil contrast examination is also valuable for diagnosing tracheal tumors, but it carries the risk of worsening tracheal obstruction and is only suitable for cases with milder obstruction. Endoscopy allows direct visualization of the tumor, providing information on its location, size, surface morphology, and mobility, and enables tissue sampling for pathological examination to determine the tumor's nature and type. However, for benign tumors with an intact mucous membrane and rich vascularity, routine biopsy is not advisable to avoid causing significant bleeding.

bubble_chart Treatment Measures

The treatment of tracheal tumors requires complete resection of the lesion to prevent recurrence and relieve tracheal obstruction. For advanced-stage cases where the tumor cannot be completely removed, the goal is to alleviate or eliminate airway obstruction and improve ventilation. Small benign tracheal tumors, especially those with a slender pedicle at the base, can be removed via electrocautery under endoscopy. Alternatively, surgical intervention may be performed, involving tracheal incision and tumor resection, or excision of the tumor along with a portion of the tracheal wall, followed by suturing to repair the tracheal defect. Malignant tracheal tumors and larger benign tumors necessitate resection of the affected tracheal segment and tracheal reconstruction. For malignant tracheal tumors, particularly adenoid cystic carcinoma, frozen section examination of the resected specimen should be conducted during surgery to determine whether submucosal cancerous infiltration persists at the tracheal resection margin. In cases of advanced-stage malignant tracheal tumors that cannot be completely resected or where resection is incomplete, local radiotherapy and/or chemotherapy may be considered based on the tumor's pathological type.