4C usually refers to the Breast Imaging Reporting Data System grading of breast lumps under ultrasound, and is the inability to assess early or advanced stages of breast cancer.
The Clinical Tumor Staging System classifies tumors into four stages based primarily on tumor size, lymph node metastasis around the tumor, and the presence of distant metastases. Of these, stage I, II and some stage III patients are referred to as early stage operable breast cancer.
4C usually refers to the Breast Imaging Reporting Data System classification of tumors after ultrasound, where grades 1 through 3 are benign lesions. 4A indicates that the patient has a 2-10% chance of developing cancer; 4B, 11-19%; 4C, 50-94%; and grade 5 indicates a greater than or equal to 95% chance of cancer, with grade 6 leading to a diagnosis of breast cancer.
Whether grade 4C breast cancer is considered early stage or not, it is recommended that patients should have a comprehensive assessment of their condition by a medical professional in conjunction with other imaging and pathology results.