220 Tumor Markers MANAGEMENT (CONT’D) Presentation Likely primary Squamous cell Cervical/rectal cancer carcinoma with inguinal lymphadenopathy Peritoneal Ovarian cancer variant, carcinomatosis primary peritoneal cancer, metastasis from colorectal or stomach cancer Liver metastasis GI (colorectal [usually otherwise well], pancreatic, esophageal, gastric, hepatic [orientals or cirrhosis], lung, breast Lung nodule(s) Metastasis (lower lobes, multiple), lung cancer (upper lobe, single) Malignant pleural Lung adenocarcinoma, effusion mesothelioma Blastic bone Prostate (most common), metastasis lung, breast Key history and physical Investigations Pelvic exam, colposcopy Anoscopy, sigmoidoscopy, CT abd/pelvis Empiric treatment(s) Lymph node dissection, chemoradiation Pelvic exam Colonoscopy, Treated as ovarian with gastroscopy, CT abd/ carboplatin, paclitaxel pelvis, CEA, CA-125 (ratio 1/20) General CEA, CA 19-9, CA 15-3, AFP, colonoscopy Gemcitabine, pemetrexed Smoking history CT chest Platinum-based doublet chemotherapy Smoking, asbestos exposure DRE Thoracentesis Thoracentesis PSA, plain X-rays of bones, bone scan Hormonal therapy if suspect prostate cancer Tumor Markers PATHOPHYSIOLOGY DEFINITION substances that can be measured quan titatively in the serum in order to detect a cancer and its organ of origin May act as surrogate of tumor bulk TYPES OF TUMOR MARKERS TUMOR-SPECIFIC PROTEINS fusion gene product in CML (bcr abl), monoclonal band in multiple myeloma ONCOFETAL ANTIGENS (non specific) expressed during embryological development and in cancer cells Examples include CEA in all GI and some other tumors, AFP in hepatocellular carcinoma and germ cell tumor, and CA 125 in ovarian cancer OVER-EXPRESSED PROTEINS (non specific) present in normal differentiated cells but lesser amount Examples include PSA in prostate cancer and CA 15 in breast cancer UTILITY OF TUMOR MARKERS screening, diagno sis, prognosis, monitor response to treatment, moni tor recurrence (after adjuvant therapy) PROSTATE SPECIFIC ANTIGEN (PSA) NORMAL RANGE