Oncology Quiz: Tumor Markers and Carcinomas

Session 12: Neoplasia IV - Incidence, Prognosis & Treatment

• The session covered neoplasia IV, focusing on incidence, prognosis, and treatment.
• Objectives included understanding malignant tumor staging (rectum, breast, prostate, bladder, Hodgkin's disease), malignant tumor grading (squamous cell carcinoma, breast cancer, colon cancer), and the biological basis for cancer treatments (radiotherapy, chemotherapy, hormone therapy, newer agents like Herceptin).
• Tumor markers (carcinoembryonic antigen, human chorionic gonadotropin, alpha fetoprotein) and screening (cervix, breast) were also discussed.
• Cancer incidence and mortality data (2008 estimates) by site and sex were presented.
• The presentation of the commonest ten cancers by primary site (2009) was shown graphically.
• The incidence rate of commonest ten cancer deaths by site (2009) in Iraq was displayed in a separate graph showing data per 100,000 population.
• Tumor behavior prediction relies on staging (TNM) and grading.

Staging (TNM)

• Staging (TNM) evaluates tumor size, lymph node status (N), and metastasis (M).
• It is based on objective pathology and clinical criteria.
• TNM is a crucial prognostic tool.
• T classifications (tumor sizes): T1 (less than 2 cm), T2 (2-5 cm), T3 (involvement of skin or chest wall).
• N classifications (lymph node status): N0 (no involvement), N1 (mobile nodes involved).
• M classifications (metastasis): M0 (no metastasis), M1 (demonstrable metastasis).
• Specific staging systems exist for different cancers, such as Dukes staging for rectal neoplasms, and Ann Arbor staging for Hodgkin's disease.
• Ann Arbor staging categorizes Hodgkin's disease based on the involved lymph node groups (I to IV) and presence of B symptoms (fever, sweats, weight loss) in addition to the location of nodes involved.

Grading

• Grading assesses tumor differentiation.
• Well-differentiated tumors closely resemble the original cell type, while poorly differentiated tumors show significant structural differences.
• Immunohistochemical stains are used to confirm differentiation.
• Specific grading systems exist for different cancers (e.g., Glasgow system for breast cancer, Gleason scoring for prostate cancer).
• Grading provides information about the tumor's aggressiveness and potential response to treatment. Grading factors include tubule formation, nuclear variation, and number of mitoses. Examples include well differentiated adenocarcinoma and moderately differentiated adenocarcinoma for breast cancer and Gleason scale for prostate cancer.

Treatment and Response Prediction

• Primary treatment depends on the tumor type and stage.
• Adjuvant treatment is given after primary treatment to reduce the risk of recurrence or metastasis.
• Radiotherapy factors include radiation type, cumulative dose, rate of delivery, and target tissue susceptibility.
• Chemotherapy targets specific stages of the cell cycle impacting rapidly-dividing cells such as bone marrow. Examples of chemotherapy drugs include Cyclophosphamide, Vincristine and Methotrexate acting on different cell division phases.
• Hormone therapy is commonly used for cancers sensitive to hormones (e.g., breast, prostate).
• Response prediction involves detecting hormone receptors (estrogen receptor) and other markers (like HER-2 amplification/overexpression) for effective treatment strategies.

Tumor Markers

• Tumor markers are substances released from tumors into the bloodstream.
• These substances aid in diagnosing cancer and assessing treatment response.
• Examples of tumor markers include alpha-fetoprotein, human chorionic gonadotropin, acid phosphatase, and prostate-specific antigen.
• Tumor markers may aid in establishing diagnosis and monitoring treatment outcomes, hence helping in follow ups.

Screening

• Screening aims to detect pre-malignant, non-invasive, and early-invasive cancers to improve prognosis and survival.
• Common screening targets are cervix, breast, large intestine, and prostate.
• Specific screening methods (e.g., Pap smear for cervix, mammography for breast) and factors including age, population at risk, cytological examination are critical.

Small Group Questions

• Various cases and accompanying questions (e.g., case scenarios of testicular teratoma, Hodgkin's disease, breast carcinoma, and colorectal carcinoma) were presented along with relevant graphics, histology and additional information to assist decision making.