2 Definitions The word “cancer” comes from the latin word for crab. The Greek word oncos means swelling and where we get the word oncology or oncologist.What is the Latin word for swelling?Tumor
3 Neoplasia (Gk. new growth) “A neoplasm is an abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after cessation of the stimuli which evoked the change.”--Dr. R. A. Willis
4 Benign vs. malignantWell-differentiated - when cancer cells resemble normal surrounding cells.benignPoorly-differentiated – when cancer cells do not resemble normal surrounding cells.malignant
12 In contrast, this hepatocellular carcinoma is not as well circumscribed (note the infiltration of tumor off to the lower right) nor as uniform in consistency. It is also arising in a cirrhotic (nodular) liver.
13 Malignant neoplasms are also characterized by the tendency to invade surrounding tissues. Here, a lung cancer is seen to be spreading along the bronchi into the surrounding lung.
14 This is an example of metastases to the liver This is an example of metastases to the liver. Note that the tan-white masses are multiple and irregularly sized. A primary neoplasm is more likely to be a solitary mass. Metastasis is the best indication that a neoplasm is malignant.
15 Stages of cancer spread: Stage 1 – confined to site of originStage 2- cancer is locally invasiveStage 3 – cancer has spread to regional structuresStage 4- cancer has spread to distant sites
16 TNM system:tumor spreadnode involvementpresence of distant metastasisStaging may influence choice of treatment
17 Staging TNM systemSize of tumor – T0, T1, T2,T3Degree of local invasion – lymph node involvementExtent of spread – metastasis
18 Patterns of spread: Metastasis Direct or continuous extensionBy lymphatics or blood streamAs clumps or as single cellsLymphatics most common
19 Distribution and common sites of distant metastases often occurs in the first capillary bed encounteredOthers show “organ tropism”Due to:Local growth factors or hormonesPreferential adherence to the surfacePresence of chemotactic factors
20 Clinical manifestations of Cancer PainUsually not in early stages60 – 80 % of terminally illPsychogenic, cultural and physiologic componentsDue to pressure, obstruction, stretching, tissue damage or inflammation
21 Clinical manifestations of Cancer Cachexia – wastinganorexiaearly satietyweight lossanemiamarked weaknesstaste alterationsaltered metabolism
22 Clinical manifestations of Cancer Anemiachronic bleedingmalnutritionmedical therapiesmalignancy in blood forming organsAdminister erythropoietin
23 Clinical manifestations of Cancer Leukopenia and thrombocytopeniatumor invasion of bone marrowchemotherapy or radiation
24 Cancer Treatment Chemotherapy Cytotoxic drugs + body defenses Single agentCombination chemotherapyAvoids single agent resistanceCan use lower doseBetter remission and cure rate
25 Cancer Treatment Radiation targets DNA kill tumor without damage to surrounding tissuestumor must be accessible
26 Cancer Treatment Surgery method of choice can remove entire tumor debulkingadjuvant chemotherapy or radiation palliation