What does basal cisterns are preserved mean? What does small mucus retention cyst within the bilateral maxillary antra mean? My husband has metastatic oligodendroglioma brain cancer. The tumor removal surgery was in May of 2008, 9 years after diagnosis and followed up with four treatments of BNCU. He was rediagnosed on 10-19-2011, the tumor was 1 cm transverse x 0.9 cm AP x 0.8 cm craniocaudal. He had 12 months of oral chemo with Temodar caps. He is followed every two months with a new MRI. November 28, 2012 the tumor measurement was 7mm in maximal craniocaudal thickness which is now 9mm (03-27-2013). The AP craniocaudal was 7 x 4 mm on 11-28-12 and is 13 x 9 mm on 3-27-2013, is that significant growth? The dr. indicated what they are looking for and lead us to beleieve there has been no change in the tumor. I told the dr. about the behavioral changes I have been observing which I had also noticed before 10-19-2011 when he was rediagnosed although now the behavioral changes are greater.