new nodule while on chemo with good response - 1272613

Dear Dr. West and team
Background: Husband diagnosed stage 3A adenocarcinoma 09/14/2015. Tumor in left lung 5x3 cm and possible one lymph node involvement close to tumor site. In addition, COPD, mild emphysema plus bronchiectasis that was indicated on his scans. We were offered pneumonectomy in major cancer center if 1) Lung function improves (it did and he passed stress test) and 2) mediastinoscopy will not reveal cancer in the rest of lymph nodes (it did not). To buy him time to improve lung function 4 chemotherapy sessions were given of Cisplatin and Alimta in high dosage. After 2nd infusion had CT scan (11/18/2015) and tumor responded by shrinking about 50%. He is also taking prednisone pill (10 mm reduced to 5mm) His shoulder pain is gone, he gained 40 lb since diagnosis.
Present situation: Pre surgical scans 12/30/2015 MRI and PET. MRI is fine but PET revealed area of inflammation 0.7 x 0.9 SUV 3.6 in his ‘good’ right lung. In his CT scan 11/18 nothing was noted of this nature. There was some area of inflammation/infection noted in right lung but our doctor did not address it at all. This SUV pop up came as a big surprise to all his team and us because he had such a good response to chemo. He got a cold without fever jus sneezing and mild runny nose 2 weeks ago. On January 4th, surgeon gave him Zpack to take for 5 days, after he got re-scaned 01/13/2016– CT scan this time. We were told yesterday that the area remains the same in size so fine needle biopsy is needed. We will have it next week.
Questions: 1. Is it unusual to have a potentially cancerous nodule to pop up while being on chemo and responding well? 2. If the nodule will turn out be malignant is the chemo considered unsuccessful even if it shrunk main tumor? 3. With the area this small they may not be able to get enough material for analysis. If this happens It could be Surgeon’s call to operate regardless of inconclusive biopsy? Would you suggest second opinion on surgery ? Thank you.