Phenethyl Isothiocyanate in Preventing Lung Cancer in Smokers

Inclusion criteria:

Initial from phone interview:

* Currently smoking 10-45 cigarettes per day for the past year;
* Between the ages of 21 and 70 years;
* In apparently good physical health with no unstable medical conditions including seizures or cancer;
* In stable and good mental health, i.e., currently do not experience unstable or untreated psychiatric diagnosis, including substance abuse, as determined by the DSM-IV criteria, during the past six months;
* Not using any other tobacco or nicotine-containing products;
* Not on methadone maintenance or stimulants such as ephedra; not a regular user of street drugs and if uses occasionally, willing to abstain during the study; not taking any drugs known to be P4501A6 substrates such as phenobarbital, rifampicin, dexamethasone, ketoconazole, methoxsalen, pilocarpine, or tranylcypromine due to their role in NNK metabolism;
* Does not average more than 21 alcoholic drinks per week;
* Willing to perform study activities such as having blood sample drawn, urine collection, multiple clinic visits;
* For female subjects of child bearing potential, not known to be pregnant or nursing, or planning to become pregnant within next 12 months.

For enrollment in the Short-Term Trial:

* Subjects who are generally healthy with liver enzyme and blood count values within the ranges shown below based on blood samples drawn at the second screening visit. Specifically:

  * White blood cells ≥ 3,000/mL
  * Total bilirubin ≤ 1.5 x upper limits of normal (ULN)
  * AST (SGOT)/ALT (SGPT) ≤ 2.5 x ULN
  * BUN and serum creatinine ≤ 1.5 x ULN

For enrollment in the Long-Term Trial:

* Participated in the short-term trial and invited to participate in the long-term trial;
* Possess the GSTM1 null-null genotype;
* Smoke 20 or more cigarettes/day with a cumulative smoking history of 20 or more pack-years (one pack-year equals to smoking a pack of cigarettes a day for one year);
* Normal liver enzymes based on blood sample drawn during 1 month wash-out;
* Determined to be a good candidate for the bronchoscopy procedure by a primary care physician.

Exclusion Criteria:

* Subjects with uncontrolled hypertension, uncontrolled diabetes mellitus, unstable coronary artery disease, history of cancer other than non-melanoma skin cancer, and pregnant or lactating women will not be eligible.