Dear Jevs2, Some centers will assign ratings to biopsy results of fine needle aspirations a
scale from 1-5. One meaning inadequate cells to diagnose , two meaning benign (non-cancerous) to five meaning malignant (cancer cells found in the sample). A C4 rating is "suspicious" for malignancy, and more tissue is likely needed to be sure of what this is, it doesn't mean a definite diagnosis of cancer.