Adjuvant chemotherapy has become an essential part for the treatment of stage IB-IIIA NSCLC patients based on 4 randomized clinical trials showing survival advantage for patients who received adjuvant CT, oncologists initially started to adapt this modality of treatment for pathologically stage IB-IIIA NSCLC patients \[4\]. Herein, NSCLC patients will be treated in the adjuvant setting with conventional doublet platinum-based chemotherapy followed by 5-azacitidine, a demethylating agent. The planned dosages to be used in this trial have been extensively studied in previously conducted clinical trials involving all therapeutic agents.
All patients will undergo thorough surgical resection of the primary lung tumor, and evidence of promoter hypermethylation of gene(s) must be present in the tumor specimen and/or blood sample (plasma or WBC). The collection of tumor specimen will be considered a priority to correlate the tumor "methylation pattern/profile" with the serum "methylation pattern/profile". If tumor specimen is not available for any reason, but the patient has at least one of the 9 targeted genes hypermethylated in the serum, the patient is eligible to be enrolled into the trial.
Treatment will consist of 2 parts:
Part A. Adjuvant chemotherapy.
Following surgical resection of NSCLC and test positive for promoter hypermethylation in at least one (1) of the targeted TSGs described, patient will start adjuvant conventional chemotherapy (doublet platinum-based chemotherapy) for stage IB-IIIA NSCLC. In the case a patient with stage IB refuses adjuvant chemotherapy, the patient still can be enrolled into Part B of the study if he/she understands the concept of the trial and sign an informed consent.
Conventional chemotherapy will be selected at discretion of the treating physicians except on those cases in which pathologic diagnosis indicates non squamous NSCLC. Those patients will be treated with pemetrexed. Patients will receive a total of 4 cycles of adjuvant chemotherapy (each cycle given every 21 days). Pegfilgrastim, a granulocyte-colony stimulating factor (G-CSF), will be allowed on day 2 at discretion of the clinician.
All patients should be premedicated prior to paclitaxel or docetaxel administration in order to prevent severe hypersensitivity reactions (HSR). Such premedication may consist of: dexamethasone 20 mg orally administered approximately 12 and 6 hours before paclitaxel or docetaxel; diphenhydramine 50 mg intravenously and cimetidine (300 mg) or ranitidine (50 mg) intravenously 30 minutes before paclitaxel. In case of pemetrexed, patient will received an injection of vitamin B-12 1,000 mcg IM a week prior to start therapy as well as folic acid 1 mg po daily a week before pemetrexed infusion and during the entire course of treatment with this antifolate agent.
The dosages and toxicities of these chemotherapy agents are very well described in the clinical setting, and patients will be managed as any other patient receiving standard chemotherapy.
Part B. Targeted therapy using 5-azacitidine.
If the patient decides not to receive adjuvant chemotherapy, the patient still can be enrolled into the study, if the patient understands the concept of chemoprevention and consents to blood sampling during 5-azacitidine administration and follow-up (informed consent signed). This part of the study consists of 6 cycles of 5-azacitidine (Vidaza®, Celgene, Summit, NJ, USA).
Four weeks after completion of adjuvant chemotherapy (day 28 from day 1 of last cycle of chemotherapy), the patient will continue his/her treatment plan with 6 cycles of 5-azacitidine. To be eligible for this part of the study, patient must have no evidence of disease (NED). Thus, patient will be assessed by CT scan chest/abdomen/pelvis with and without intravenous contrast prior to initiating Part B. In case of iodine allergy/anaphylaxis history, patient will be assessed with MRI. Progression of disease will be defined by RECIST criteria.
Patient will receive 5-azacitidine at a dose of 75 mg/m2 intravenously daily on day 1-5 every 28 days for 6 cycles. Biological correlatives will be performed during this period. Toxicity management is described in section 6.0. The use of growth factor support (either erythropoietin stimulating agents or G-CSF) will be also allowed at discretion of the treating physician.
Anatomical Studies:
All patients will have surgical resection of the primary tumor. Pieces of the resected tumor and non-tumor lung tissues that are not required for pathological evaluation will be frozen in optimum temperature compound (OTC) and saved for molecular analysis.
As part of the enrollment process, patient will be assessed through CT scan of the chest/abdomen/pelvis with and without intravenous contrast or with MRI in case of contraindication for iodine contrast, prior to initiate Part B of the treatment (confirming clinically and radiological "no evidence of disease-NED"). Another assessment will be performed 4 weeks after the last dose of 5-azacitidine (to confirm NED status). Patient will be clinically followed up every 3 months until completion of 2 years post-treatment. Imaging tests will be performed every 3 months with CT scan as part of the standard follow-up until completion of 2 years post-surgery. After 2 years of post-treatment completion, patient will be followed up every 6 months in the clinic and also by radiographic studies until completion of 5 years post-treatment. In the case of clinical suspicion for progression, patient will undergo a thorough and complete work-up to rule out this possibility. This may include imaging diagnostic tests, biopsy, or other tests and procedures.
Biological Correlatives:
The premise of the study is that certain loci will be hypermethylated in the lung cancer specimen of the patients. For some loci (which we shall call Type I) the tumor will show significantly elevated methylation compared to adjacent histologically normal tissue, thus providing a cancer-specific methylation signal. Other loci (which we will refer to as Type II) may be methylated in the tumor as well as in the adjacent "histologically" normal tissue and/or WBCs. These loci will not be cancer-specific markers, though they may indicate precancerous changes or they may be indicative of "cancer risk". Their hypermethylation may be age-associated or environmentally induced, yielding "field effects" or "field defects". Field defects would consist of molecular alterations (in this case hypermethylation) that are not yet visible as histological changes.
Independent of whether a hypermethylated locus is specific for overt cancer (Type I) or not (Type II), it would be of interest for the study. These Type II changes would be "hypothesis generating". Since it has been well documented in the literature that DNA from cells can be shed into the blood stream (more so in the case of cancer patients), it would be expected that at least for some of the loci that are hypermethylated (Type I and II), this methylation would be detectable in the plasma. Tumor tissue methylation will be correlated with serum obtained at the time of tumor resection.
It might be expected that complete resection would lead to a reduction or complete disappearance in the methylation signal for Type I loci in the plasma, since the source of the signal has been removed. Type II also shows methylation in the tissue adjacent to the tumor, these loci might continue to provide signal in the plasma (though it may be somewhat diminished).
Type I loci would therefore be of great use to verify complete resection and to monitor recurrence (one would anticipate the signal to increase again as the cancer grows back), while Type II loci would be a great tool to monitor the efficacy of demethylating drugs. It must be acknowledged that the spectrum of Type I and Type II methylation may not be sharply delineated.
