Neoplasia VII

• Factors affecting prognosis of neoplasms include:

  • Grade
  • Stage
  • Type
  • Size
  • Site
  • Host response
  • Adequacy of therapy
• Tumour Grade:

  • Histological assessment of the degree of differentiation of the tumour
  • Three grades: Well differentiated/Low grade, Moderately differentiated/Intermediate grade, Poorly differentiated/High grade (poor prognosis)
  • Differentiation refers to the degree to which the tumour resembles mature tissue and the degree of nuclear abnormality
• Cytological Features used in assessing tumour grade:

  • Hyperchromasia
  • Pleomorphism
  • Increased nuclear/cytoplasmic ratio
  • Mitotic activity
• Architectural Features used in assessing tumour grade:

  • Degree of gland formation (e.g., Adenocarcinoma)
  • Degree of maturation of epithelium
• Prognosis of neoplasms is also influenced by the Stage:

  • Staging is essential to decide the treatment required
  • TNM staging system: T (Size of tumour), N (Number of positive lymph nodes), M (Number of metastases)
  • Some cancers have specific staging systems
• Importance of the Sentinel node:

  • First node in a regional lymphatic basin that receives lymph flow from a primary tumour
  • Commonly examined in breast carcinoma and malignant melanoma
  • Negative sentinel node may avoid further nodal dissection, reducing side effects
• Sentinel Node Examination process:

  • Surgeon identifies the sentinel node by injecting blue dye and/or an isotope at the tumour site
  • Blue dye/isotope drains to the sentinel node first
  • Surgeon removes the node if it shows blue color
  • False negative rate may occur due to blocked lymphatics or alternative drainage pathways
• Prognosis of neoplasms is influenced by the Type of neoplasm:

  • Prognosis varies according to the type of neoplasm
  • Example: Malignant melanoma of skin has a bad prognosis compared to basal cell carcinoma
• Prognosis is also affected by the Size of the tumour:

  • Many staging systems include size criteria for different types of cancers
  • Example criteria for Breast Carcinoma, Lung carcinoma, and Squamous cell carcinoma of the skin
• Prognosis can be influenced by the Site of the tumour:

  • Skin neoplasms generally have a better prognosis than abdominal neoplasms due to earlier clinical presentation
• Host Immune Response can impact prognosis:

  • A lymphocytic infiltrate in a tumour is a good prognosticator
  • Reflects the body's ability to generate an immunological response against the tumour
• A lymphocytic infiltrate in a tumor is a good prognosticator, reflecting the body's ability to generate an immunological response against the tumor
• Complete removal is the most important measure of the adequacy of treatment for tumors
• Margins of the tumor are inked in the pathology department to give a measurement of the margin of excision
• When malignancy is suspected, the specimen is often covered with ink to mark the margins of the specimen
• Different colored inks can be used to identify different areas if needed
• General health status of the patient is a non-pathological prognostic factor
• It is important to assess if the patient is fit to withstand treatment
• Discussion at Multidisciplinary Team Meeting is crucial for evaluating the patient's general health status
• Malignant neoplasms can kill the patient by spreading and metastasizing to distant sites
• Routes of tumor spread include direct invasion to adjacent tissues, metastasis via lymphatics, blood vessels, transcoelomic spread, and perineural spread
• Direct invasion involves the spread of the tumor to adjacent tissues
• Lymphatic spread can lead to lymphadenopathy and other clinical presentations
• Vascular spread occurs through blood or lymphatic invasion and commonly metastasizes to the lung, liver, bone, brain, and lymph nodes
• Transcoelomic spread refers to tumor metastasis across a body cavity, such as peritoneum in ovarian cancer
• Perineural invasion is common in certain tumors like ductal adenocarcinoma of the pancreas and prostatic adenocarcinoma
• Enzyme degradation of basement membrane and connective tissue, reduced cell adhesion, increased vessel formation, and tumor embolization facilitate neoplasm spread
• Common neoplasms that metastasize to bone include breast, prostate, lung, thyroid, and renal cancers
• Treatment of malignant neoplasms involves surgery, radiotherapy, chemotherapy, growth receptor blocking agents, small molecule inhibitors, anti-angiogenic therapies, and immunotherapy
• Discussion at Multidisciplinary Team Meetings involves pathologists, surgeons, oncologists, radiotherapists, radiologists, and cancer care nurses
• Hormonal therapy examples like Tamoxifen can be used to treat neoplasms with estrogen receptors
• Monoclonal antibodies like Trastuzumab/Herceptin can target specific receptors in breast cancer cells
• Small molecule inhibitors like Imatinib inhibit intracellular kinase components of transmembrane receptors, affecting signaling pathways in cancer cells