Treatment Alternatives in Adult Rare Disease; Assessment of Options in Idiopathic Subglottic Stenosis North American Airway Collaborative PR-02 Study (NoAAC PR-02 Study)

Idiopathic subglottic stenosis (iSGS) is a rare disease in which the trachea narrows for no known reason. Although uncommon (with an estimated incidence of 1:400,000 persons per year), both the disease and its therapies profoundly affect patients' ability to breathe, communicate and swallow. Breathing difficulties (i.e. dyspnea) is the hallmark symptom and the primary cause of death and disability. However, patients can also experience debilitating voice changes and swallowing problems due to the condition or its treatment.

People with this disease often require several surgeries per year. A variety of treatments have been advanced to manage iSGS but are generally categorized into: 1) endoscopic dilation of the tracheal stenosis (accomplished with rigid instruments or inflatable balloons); 2) endoscopic resection of the stenosis (with prolonged medical therapy after surgery); or 3) open neck surgery with resection of the affected tracheal segment with end-to-end anastomosis. Each patient can require repeated surgeries to keep their trachea open, which increases odds of treatment side effects and complications. All approaches have unique and often disabling associated side effects, which can significantly affect a patient's quality of life.

Because the disease is rare, it is difficult for patients to find good information so that they can understand the spectrum of treatment options. This is particularly difficult because most patients present with severe breathing trouble and need treatment quickly, limiting their ability to explore options. Additionally, there is a general lack of high-quality, reliable, and accessible data to inform individual patient decision-making. Imperfect information and limited evidence on treatment outcomes complicate patient decision-making as they try to balance survival, symptoms, and quality of life considerations.

Beyond the gaps in understanding the relative effectiveness of the different treatments available, no studies have explored functional outcomes in iSGS (i.e. how well patients breathe, speak, and swallow after treatments). These endpoints are important to patients and are arguably a primary determinant in decision-making. Direct engagement with patients is critical to understand these quality of life considerations, since patient and physician perspectives aren't always the same. For example, results show that endoscopic dilation is associated with a higher rate of disease recurrence and thus need for repeated surgery. Meanwhile, open tracheal resection is a major surgery with significant immediate perioperative risks and has been associated with alterations in voice and swallowing. Open tracheal resection appears to reduce the risk of disease recurrence, but the degree of benefit, and the trade-offs associated with this approach are unanswered questions.

The proposed study from the North American Airway Collaborative (NoAAC PR- 02) is designed to fill this void. Our prospective study will directly compare the effectiveness of standard of care treatments and assess their associated quality of life tradeoffs in iSGS patients.