Tumor Staging (LO3)
These three letters name the AJCC system used to stage colon cancer
What is TNM
T = depth of invasion through the wall
N = regional node involvement
M = distant metastasis (M0/M1).
This older fecal occult blood test uses a plant resin that detects the pseudoperoxidase activity of heme, turning blue, and can trigger false positives when red meat/peroxidase-rich vegetables are ingested prior to testing
What is the guaiac (gFOBT) test
This transporter carries dietary ferrous iron across the apical membrane of duodenal enterocytes
What is DMT1 (divalent metal transporter 1)
About 10–15% of colon cancers arise from defects in this DNA repair system
What is mismatch repair (MMR)
FOLFOX combines oxaliplatin and 5-fluorouracil with this reduced-folate agent
What is leucovorin
This stage of cancer is characterized by T1-T2 and N0
What is Stage 1
The FIT uses antibodies against this human protein, making it more specific for lower-GI bleeding and requiring no dietary restriction
What is human globin (hemoglobin)
This plasma protein binds iron and delivers it to tissues via transferrin receptor 1
What is transferrin
Loss of this tumor-suppressor gene is the initiating event in most (microsatellite-stable) colon cancers
What is APC
Leucovorin boosts 5-FU's effect by stabilizing this three-molecule complex with thymidylate synthase
What is the ternary complex
This T category describes a tumor that has grown through the muscularis propria into the pericolic tissue, but not through the serosa
What is T3
The MCV of 78.2 fL (low) tells you the red cells are this size, pointing toward iron deficiency
What is microcytic (small)
This is the only cellular iron-export protein, present on enterocytes and macrophages
What is ferroportin
APC normally promotes degradation of this protein; when APC is lost, it accumulates and drives Wnt target-gene transcription
What is β-catenin
This platinum agent in FOLFOX forms DNA adducts and crosslinks that inhibit DNA synthesis
What is oxaliplatin
The presence of distant spread (M1) places a patient in this overall stage
What is Stage IV
The ferritin of 13 µg/dL (low) is the key value showing that these are depleted
What are total-body iron stores
These reticuloendothelial cells recycle most of the body's daily iron by phagocytosing senescent red blood cells
What are macrophages
Defective mismatch repair produces this molecular signature of unstable repetitive DNA sequences
What is microsatellite instability (MSI)
Bevacizumab is a humanized monoclonal antibody that binds this circulating growth factor to block tumor angiogenesis
What is VEGF (VEGF-A)
This special N designation means tumor deposits are present in the pericolic fat without any positive regional lymph nodes
What is N1c
Unlike anemia of chronic disease, this iron-study lab value is elevated in iron deficiency because the liver makes more transferrin to scavenge iron
What is TIBC (total iron-binding capacity)
This enzyme oxidizes ferrous iron back to ferric iron as it exits the enterocyte, so it can load onto transferrin
What is hephaestin
In sporadic MSI colon cancers, the MMR gene MLH1 is most often silenced by this epigenetic mechanism (be specific)
What is promoter hypermethylation
Bevacizumab is added to 5-FU-based chemo primarily in this stage/setting of colorectal cancer
What is metastatic (advanced) colorectal cancer