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EVOLUTION OF MULTIMODAL THERAPY FOR RECTAL CANCER
Epidemiology
• 2000: 130,200 new cases of colorectal cancer (36,400 rectal CA)
• In US: 6% lifetime risk, increases with age
• 75% of cases sporadic
• Remainder in patients with IBD, FAP, HNPCC, and strong family history
Clinical Presentation
• Abdominal pain (46.8%)
• Rectal bleeding (29.6%)
• Unexplained anemia (17.8%)
• Constipation (20.2%)
• Diarrhea (16.2%)
• Obstruction, change in caliber of stool
Diagnostic Workup
• H&P
• Labs: CBC, LFT’s, electrolytes, urinalysis
• Imaging: CXR, CT Scan, endorectal ultrasound
• Procedures: proctoscopic examination, full colonoscopy with biopsies
TNM Staging
• Primary Tumor (T)
– T1: Invades submucosa
– T2: Invades muscularis propria
– T3: Invades through muscularis propria into serosa or perirectal tissues
– T4: Tumor invades into peritoneal cavity or contiguous organs
TNM Staging (cont.)
• Lymph Nodes (N)
– N0: No regional lymph node involvement
– N1: Involvement of 1 to 3 local lymph nodes
– N2: Involvement of 4 or more local lymph nodes
– N3: Involvement of central nodes
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TNM staging (cont.)
• Distant Metastasis (M)
– M0: No distant metastasis
– M1: Distant metastasis
Treatment
•
Four goals in the successful management of rectal cancer
– Cure
– Local control
– Restoration of intestinal continuity
– Preservation of the anorectal sphincter, sexual and urinary function
Treatment (cont.)
• Surgical resection is the cornerstone of curative treatment
• Chemotherapy and radiation help achieve four goals of management
– May decrease local recurrence, increase survival, and allow sphincter preservation when
compared to surgery alone
Post-op Chemoradiation
• Series of large scale randomized trials of postoperative 5-FU/radiation
– significantly reduce local recurrence
– improve disease free and long term survival
– NIH (1990): recommended post-op chemoradiation be the standard of care following
resection of stages II and III rectal cancer
Pre-Op Radiotherapy
• Theoretical advantages:
– Reduction in size of