Cancer of the Colon and Rectum Flashcards
Colorectal
(from PBRRO1)
Which is FALSE regarding the relationship of the colon and the peritoneum?
I. The posterior and superior surfaces of the ascending and descending colon are in direct contact with the retroperitoneum, whereas the anterior surface is draped with peritoneum.
II. The posterior attachments can prevent significant mobility, increasing the difficulty of surgical resection.
III. The transverse colon is completely surrounded with peritoneum and supported on a long mesentery.
IV. As the sigmoid colon evolves distally into the rectum, the peritoneal coverage
recedes.
I only II only III only IV only I & III only II & IV only III & II only IV & I only ALL
I only
It’s the posterior and “lateral” surfaces.
Uh-huh. yeah. ganyang klase ng tanongs.
Colorectal
(from PBRRO1)
Which is FALSE regarding the relationship of the rectum and the peritoneum?
I. The upper one-third of the rectum is draped with peritoneum anteriorly and on both sides.
II. As the middle one-third of the rectum moves deeper into the pelvis, only the lateral surfaces are covered with peritoneum.
III. The lowest one-third of the rectum is devoid of peritoneal covering and in close proximity to adjacent structures, including the bony pelvis
II.
As the middle one-third of the rectum moves deeper into the pelvis, only the anterior surface is covered with peritoneum, which forms the posterior border of the rectouterine pouch or rectovesical space.
Colorectal Cancer
Give 3 main risk factors for the development of rectal cancer?
increasing age
male sex
excessive alcohol intake
Colorectal Cancer
Tumors possessing a high frequency of microsatellite instability have more favorable outcomes and lower likelihood of developing metastatic disease.
TRUE or FALSE?
may be more TRUE as studies suggest.
Colon Cancer
Cancers of the right colon are often _______ and commonly associated with
___________ due to ___________, resulting in delayed diagnosis.
Cancers of the left colon and sigmoid colon are often deeply invasive and annular (“apple core lesions”) and commonly presents with ___________.
Right
exophytic; iron deficiency anemia; occult blood loss
Left
obstruction, rectal bleeding, and alteration in bowel habits.
Colorectal Cancer
Age to start screening in the general population (average-risk)
Also in patients with single, first-degree relative with CRC diagnosed after 60y.
50y
Colorectal Cancer
Age to start screening in patients with FAP?
10 to 12 years until 35 to 40 if negative.
Colorectal Cancer
Age to start screening in patients with HNPCC?
20 to 25 years
or 10 years prior to earliest familial CRC diagnosis.
Colorectal Cancer
Age to start screening in patients with IBD?
8 to 10 years after initial diagnosis
Colorectal Cancer
Given the data in favor of screening, health organizations such as the
American Cancer Society (ACS), the United States Preventive Services Task
Force, and the American College of Radiology recommend screening in
average-risk individuals starting at age 50.
What are the tests advocated by the ACS that
detect adenomatous polyps and cancer?
- Flexible sigmoidoscopy every 5 years.
- Double-contrast barium enema every 5 years.
- Computed tomography (CT) colonography every 5 years.
- Colonoscopy every 10 years.19
- Guaiac-based fecal occult blood, fecal immunohistochemical, and stool DNA
tests may be performed for CRC, but not polyp, detection
Colorectal Cancer
CT appears to be more useful in identifying enlarged pelvic lymph nodes and metastasis outside the pelvis than the extent or stage of the primary tumor.
Why is CT limited in its utility in the assessment of smaller primary cancers?
CT does not permit the visualization of the layers of the rectal
wall
Colorectal Cancer
The ability of CT scans for
detecting distant metastasis (DM), including pelvic and para-aortic lymph nodes, is higher than for detecting perirectal nodal involvement. Therefore, any lymphadenopathy near the rectum seen on a CT scan should be considered abnormal.
TRUE or FALSE?
True
Colorectal Cancer
For rectal malignancies, endoscopic ultrasound (EUS) or pelvic magnetic resonance imaging (MRI) can assess primary disease and evaluate nodal extent.
What are the advantages of MRI vs. EUS?
- less operator dependent
- able to assess proximal and stenotic tumors
- able to to visualize lymph nodes outside the perirectum (larger field of view)
- able to characterize lymph nodes other than from size-basis.
- able to determine lateral extent of disease
Colorectal Cancer
What is the preferred imaging procedure (test of choice) to evaluate hepatic metastases in patients with CRC?
A. CT scan of the liver with contrast
B. Liver MRI
C. Liver ultrasound
D. PET-CT scan
B.
Colorectal Cancer
Prognostic factors influencing survival in CRC
depth of invasion into and beyond bowel wall
number of involved RLN
+/- distant metastases
Colorectal Cancer
2017 AJCC staging.
Identify the T-stage:
Invasion of the lamina propria
Tis
Carcinoma in situ
intraepithelial (intramucosal)
invasion of lamina propria (without extension through the muscularis mucosa)
Colorectal Cancer
2017 AJCC staging.
Identify the T-stage:
Tumor invades muscularis propria
T2
Colorectal Cancer
2017 AJCC staging.
Identify the T-stage:
Tumor invades muscularis mucosa
T1
Tumor invades submucosa (through the muscularis mucosa but not into the muscularis propria)
Colorectal Cancer
2017 AJCC staging.
Identify the T-stage:
Tumor invades through the muscularis propria into the pericolorectal tissues
T3
Colorectal Cancer
2017 AJCC staging.
Identify the T-stage:
Tumor invades through the visceral peritoneum
T4a
Colorectal Cancer
2017 AJCC staging.
Identify the N-stage:
7 or more regional lymph nodes
N2b
N2 is 4 or more
therefore 4-6 is N2a
Colorectal Cancer
2017 AJCC staging.
Identify the N-stage:
2-3 regional lymph nodes
N1b
N1a is 1 regional lymph node
Colorectal Cancer
2017 AJCC staging.
Identify the N-stage:
No regional nodes, but there are tumor deposits in the subserosa, mesentery, or nonperitonealized pericolic or perirectal tissues
N1c
Colorectal Cancer
2017 AJCC staging.
Identify the M-stage:
2 or more sites or organs
M1b
m1a is one organ
m1c is peritoneal surface with or without organ metastases
Colorectal Cancer
2017 AJCC staging.
Identify the stage group:
T3 N0 M0
IIA
Colorectal Cancer
2017 AJCC staging.
Identify the stage group:
T2 N0 M0
stage I
T1-2 N0 M0 are both stage I
Colorectal Cancer
2017 AJCC staging.
Identify the stage group:
T4a N0 M0
IIB
T4b N0 M0 is IIC
Colorectal Cancer
What is Dukes C in staging?
any node+
Colorectal Cancer
What is Dukes B in staging?
locally advanced but node negative.
T3-T4b N0 M0
Colorectal Cancer
What is the main change from AJCC 2010 to 2017?
addition of M1c
Colon Cancer
How many lymph nodes should be excised for adequate staging?
12
Colon Cancer
The addition of chemotherapy in resected stage III (node +) colon cancers resulted in improved OS and DFS.
What are the standard combinations of chemotherapeutic agents being used?
FOLFOX
(folinic acid/FU/oxaliplatin)
XELOX
(capecitabine/oxaliplatin)
Colon Cancer
The addition of irinotecan (FOLFIRI) to folinic acid+FU in the adjuvant setting
showed improved DFS.
TRUE or FALSE?
False.
No OS or DFS benefit
Colon Cancer
Based on the MGH experience, T4 tumors significantly benefit from adjuvant RT compared to T3 tumors who received adjuvant RT when compared to non-irradiated population.
TRUE or FALSE?
TRUE.
Both benefited, however, only T4 tumors significantly benefited.
Colon Cancer
Adjuvant RT
What is the initial dose to large fields?
45/1.8/25
Colon Cancer
Adjuvant RT
What is the total dose for T4 tumors?
50 to 60 Gy