This trial was to evaluate the efficacy of intratumoral PTS injection in alleviating airway obstruction and dyspnea by improving the percentage of lumen patency of patients with central air way NSCLC tumor severe obstruction.

1. Local intratumoral injection of para toluenesulfonamide (PTS) via bronchoscopy could alleviate airway obstruction for patients with central air way NSCLC tumor severe obstruction, which contributed to the shrinkage of target tumor lesions in a short period, with an objective response rate of 66% and an improvement rate of luminal tumor obstruction of 70% in the end-of-treatment period.
2. Patient's pulmonary function, atelectasis and quality of life were improved significantly after treatment, indicating that PTS treatment cuold relieve the symptoms of air way obstruction and provide clinical benefits to the patients.
3. Adverse events were mainly blood streaked sputum, injection site haemorrhage, cough, pyrexia and oropharyngeal pain, without reporting of potential risks. Common study drug related adverse events included injection site haemorrhage, cough, and blood streaked sputum and oropharyngeal pain. The multi-center clinical study conducted strictly in accordance with Standard Operation Procedures for the Use of a Standard Bronchoscope in Local Intratumoral PTS Injection showed that PTS had good safety and tolerability and that the procedural risks of intratumoral PTS injection via bronchoscopy could be controlled.
4. The advantages of PTS for treatment of airway lung cancer obstruction included significant efficacy, good safety, large applicable population; relatively simple equipment conditions and operation, thus it could be spread easily. PTS is also expected to be used in the treatment of central lung cancer with acute airway obstruction in combination with other treatments (such as stent implantation), which provides a new drug treatment to patients with airway lung cancer obstruction. PTS can complement with other treatments, which is expected to improve the treatment efficacy significantly.

Inclusion Criteria:

• Male or female inpatients, aged 18 to 83 years old.
• Patients with central air way non-small cell lung cancer (NSCLC) severe obstruction; definition of severe airway obstruction: ≥1/2 trachea is obstructed by tumor; and/or block ≥2/3 of primary bronchi, right and middle bronchi. And the longest diameter of the lesion > 0.5 cm.
• Pathologically confirmed lung cancer.
• Patients with tracheal tumor lesions suitable for local intratumoral injection via fibro-bronchoscopy.
• At least one measurable lesion that could be evaluated by imaging examination (bronchoscopy, CT, MRI or X-ray etc.) according to the Response Evaluation Criteria in Solid Tumors.
• Blood platelet count ≥ 100,000/mm3.
• Subjects who were able to understand and comply with the trial protocol and give written consent.

Exclusion Criteria:

• Brain metastases.
• History of cardiovascular diseases, including congestive heart failure > New York Heart Association (NYHA) Grade II. Patients with unstable angina pectoris (angina pectoris symptoms at rest), recent angina pectoris (occurred in the recent 3 months) or with myocardial infarction in recent 6 months must be excluded.
• Severe infections or dysbolism.
• Poor hepatic functional reserve or severe hepatocirrhosis, with abnormal blood coagulation indicators.
• Poor general conditions or cachexia.
• The target lesion had been treated with radiotherapy within 6 months.
• Pregnant or breast-feeding woman.
• Known hypersensitivity to PTS or related compounds.
• Lung cancer lesions not suitable for local treatment.
• Any other reason deemed reasonable by the investigator.