A 75-year-old man with an extensive pipe smoking history and coronary artery disease was initially evaluated for a persistent productive cough and streaky hemoptysis for several years. Chest roentgenogram was normal. Computed tomography (CT) was insignificant except for an irregular mass involving the anterior tracheal wall (Fig. 1). He denied shortness of breath, weight loss, or other constitutional symptoms except for a bothersome cough that occurred on an hourly basis.
Bronchoscopy showed friable exophytic masses involving the anterior tracheal wall, starting 1 to 2 cm below the vocal cords and extending approximately 5 cm in length. The largest mass was at the midtrachea, obstructing more than 50% of the airway lumen. The rest of the bronchial tree was clear at inspection (Fig. 2A).
The biopsy specimens showed a papillary squamous cell carcinoma in-situ stage without any evidence of human papilloma virus infection (Fig. 3). Subsequent positron emission tomography scanning showed increased midtracheal uptake of fluorodeoxyglucose. This was consistent with a primary tracheal tumor in-situ stage.
Treatment options included a tracheal segmentectomy versus endotracheal ablation with adjuvant chemoradiotherapy. The patient chose a less invasive intervention. Subsequently, under general anesthesia, using both rigid and flexible bronchoscopes, the tracheal tumors were excised with repeated application of electrocautery, argon photocoagulation, and cryotherapy followed by balloon dilatation achieving more than 90% luminal patency. Starting 2 months after the procedure, he received a total of 6660 cGy of external beam radiotherapy at 180 cGy per fraction daily for 37 fractions. Last surveillance bronchoscopy performed 14 months after the initial ablation and 10 months after radiotherapy did not show any tumor recurrence (Fig. 2B). Subsequent positron emission tomography-CT scanning was negative for any abnormal uptake. Currently, the patient is 16 months in remission and is being followed closely for any tumor recurrence.
The trachea is a fibromuscular tube supported by cartilaginous rings that extends from the cricoid cartilage to the carina. It measures 10 to 13 cm in length and 2.0 to 2.5 cm in diameter; it is lined by a ciliated pseudostratified epithelium with goblet cells. Under the epithelium is a lamina propria, and together these 2 tissues constitute the mucosa. Below the mucosa are the submucosa and adventitia.1
Primary tumors of the trachea are exceedingly rare, occurring at 2.6 new cases per 1 million people annually.2 It is composed of both benign and malignant types. In adults, 80% to 90% of the tumors are malignant, whereas in children, most are benign.3,4 The most common symptom is exertional dyspnea; others include stridor, wheezing, cough, difficulty in clear&1hyphen-qj;ing secretions, recurrent pneumonia, hemoptysis, and hoarseness. Weakness, weight loss, and dysphagia may be observed with metastatic tumors and are poor prognostic signs.5,6 Chest roentgenogram, CT, spirometry, bronchoscopy, and tissue diagnosis are often helpful. Radiographic features of tracheal tumors that suggest a benign lesion include smooth, sharply demarcated lesions less than 2 cm in size that are completely intraluminal with limited tracheal involvement.3,4 Papillomas (benign neoplasms) have multiple slender, finger-like projections supported by central fibrovascular cores and covered by a typical, stratified squamous epithelium. They are typically caused by human papilloma virus types 6 and 11, with rare cancerous transformation.3,4 In general, primary benign tracheal tumors have good prognosis and rare recurrence.1,7 Recommended treatment for these tumors is tracheal reconstruction with primary anastomosis. Patients with exophytic tumors or tumors in anatomic locations that might make resection difficult are potential candidates for endoscopic resection. Current methods include coring out the tumor with a rigid bronchoscope and biopsy forceps, cautery excision, cryotherapy, and laser photocoagulation.1,7
In contrast, malignant primary tracheal tumors (MPTTs) are larger, with indistinct margins that extend circumferentially and longitudinally within the trachea and invade the wall.1 Squamous cell carcinoma (SCC) is the most common type, followed by adenoid cystic carcinomas (ACC).2,7 SCC is more prevalent in male smokers in the sixth to seventh decades of life. They may occur at any airway level, may be single or multiple, and usually have ulcerated exophytic or sessile growth. Approximately 50% of the tumors are unresectable at the time of presentation because of the extent of the primary lesion or the presence of metastatic disease.1,7 ACC is seen in all age groups and usually arises in the trachea or main bronchi. There is no predilection for sex, race, or cigarette smoking. Histologically they are nonencapsulated, slow-growing, low-grade malignancies arising from the respiratory epithelium. They typically push mediastinal structures aside rather than invade them.1,7 For MPTTs, tracheal resection with adjuvant radiotherapy is recommended. If metastasis is detected in the superior mediastinal nodes, the likelihood of complete resection and long-term survival is poor.1,7 Their overall 5-year survival is dismal, although localized disease has better survival when compared with regional or distant diseases.2
According to a recent large observational cohort study of patients with primary tracheal tumors recorded in the National Cancer Institute's Surveillance, Epidemiology, and End Results 1973 to 2004 database, there are 578 reported cases wherein 55.7% are men and 44.3% are women. SCC is the predominant type (44.8%), followed by ACC (16.3%). Localized, regional, and distant disease was found in 24.2%, 36.7%, and 18.7% of the cases, respectively. The overall 5-year survival for all patients was 27.1%; it was 46% for those with localized disease. For those with SCC and ACC, the 5-year survival rates are 12.6% and 74.3%, respectively; 24.7% and 90.5% are those with localized disease SCC and ACC, respectively. Of all the cases, a significant number of patients did not receive any cancer-directed local therapy; 34.3% did not undergo surgery and 29.1% did not receive any radiotherapy.2
Studies have shown that the treatment of choice for primary tracheal tumors is tracheal resection with or without radiotherapy. A recent review of 37 tracheal tumor cases, consisting of 38% benign and 62% malignant cases, showed that most benign tumors were treated successfully without recurrence, whereas papillomas were difficult to manage. Among MPTTs, surgery is recommended as the first choice of treatment, regardless of the histologic type, if the tumors are respectable.8 According to Schneider et al's9 analysis of 14 cases with primary tracheal tumors treated by resection and reconstruction of the trachea, there was significant associated morbidity and mortality. The histologic findings in these cases were ACC (n=7), SCC (n=2), mucoepidermoid carcinoma (n=2), carcinoid tumor (n=1), and benign tumor (n=2). Eight patients required preoperative neodymium-yttrium, aluminum, garnet laser photoresection. Six were treated by postoperative external radiotherapy and in 3 cases this was combined with endoluminal brachytherapy. Two major postoperative wound-healing impairments occurred at the anastomosis. Four minor wound-healing disorders were treated with therapeutic bronchoscopy. Two patients died postoperatively with mediastinitis. A local recurrence was observed in 2 cases. There were 5 long-term survivors (>6 y) of ACC or mucoepidermoid carcinomas. Despite significant associated morbidity and mortality, extensive tracheal resection is still the recommended treatment for MPTTs. Interventional endoscopy may play an integral part of the modern tracheal surgery.
In summary, we report a case of short-term success with excisional ablation of a primary tracheal papillary SCC in-situ stage, which was deemed unresectable because of the extent of the primary lesion, the patient's age, and his comorbid conditions. Our patient will require long-term surveillance to ensure the adequacy of tumor ablation, maintenance of airway patency, and documentation of any local recurrence, considering that these tumors may recur after a limited bronchoscopic excision. Nevertheless, the advantages of a modern pulmonary interventional approach should not be ignored in view of the reduced morbidity and cost and the relative noninvasive nature of this approach compared with the complexity of surgical excision.9,10 In addition, some of these patients may be high-risk surgical candidates because of diminished pulmonary reserve and poor coexistent medical conditions. The less-invasive bronchoscopic approach also highlights the need for careful follow-up and surveillance in such patients to document the presence of recurrence and appropriate intervention should recurrence be noted.
1. Cummings CW, Flint PW, Harker LA, et al. Cummings Otolaryngology: Head & Neck Surgery. 4th ed. Philadelphia: Elsevier Mosby; 2005.
2. Urdaneta AI, Yu JB, Wilson LD. Population based cancer registry analysis of primary tracheal carcinoma. Am J Clin Oncol. 2010 Jan 15 [Epub ahead of print].
3. Gaissert HA. Primary tracheal tumors. Chest Surg Clin N Am. 2003;13:247–256.
4. Mathisen DJ. Tracheal tumors. Chest Surg Clin N Am. 1996;6:875–898.
5. McCarthy MJ, Rosado-de-Christenson ML. Tumors of the trachea. J Thorac Imaging. 1995;10:180.
6. Wood DE. Management of malignant tracheobronchial obstruction. Surg Clin North Am. 2002;82:621.
7. Allen MS. Malignant tracheal tumors. Mayo Clin Proc. 1993;68:680–684.
8. Ahn Y, Chang H, Lim YS, et al. Primary tracheal tumors: a review of 37 cases. J Thorac Oncol. 2009;4:635–638.
9. Schneider P, Schirren J, Muley T, et al. Primary tracheal tumors: experience with 14 resected patients. Eur J Cardiothorac Surg. 2001;20:12–18.
10. Shah H, Garbe L, Nussbaum E, et al. Benign tumors of the tracheobronchial tree: endoscopic characteristics and role of laser resection. Chest. 1995;107:1744–1751.