Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Molly M. Cone, MD Assistant Professor of Surgery Vanderbilt Medical Center November 14, 2014 No disclosures o Review screening options and recommendations for colorectal cancer o Understand criteria for referral for genetic testing in patients with colon cancer o Learn about current surgical options for patients with colorectal cancer Epidemiology: o In 2014: • 96,830 colon cancer diagnosed • 40,000 rectal cancer diagnosed o Lifetime risk 1/20 (5%) o 3rd leading cause of cancer related deaths in US • 50,310 expected to die of CRC in the US this year o Worldwide- responsible for over 650,000 deaths annually (WHO) • • Both incidence and deaths from colon and rectal cancer have been declining Except in those <50 yrs Why screen? Cost effectivelarge number of incident cases, long duration of disease manifestation, and high mortality o simple methods for detection and reasonable treatment options o Saves liveso screening for CRC not only detects cancer earlier, but also allows the clinician to intervene and change the course of the disease. x DCC 18q 8-10 years x Problems with screeningo multiple methods lead to considerable confusion regarding which method is best and the optimal timing . o confusion causes physicians to reduce the importance paid to CRC screening This reduces the number of patients who ultimately get screened Physician Recommendation o Patients indicate as the single most important factor in deciding to undergo screening From National Cancer Institute: o >42% of patients were unaware of potential screening options o only 35% of respondents were aware that colonoscopy could actually detect CRC Fecal Occult Blood Test (FOBT) o only screening test which has shown efficacy in prospective randomized controlled trials Fecal Immunochemical based stool Tests (FIT) o more specific for hemoglobin, this test avoids some of the false positive results of FOBT DNA stool Assays (sDNA) o Cells shed from the polyp/cancer contain DNA mutations that can be used as a biological marker for cancer detection Serum Markers o Two most studied- CEA, CA 19-9 • CEA used as biologic marker for progression of cancer, but only 30% sensitivity rate for detection • CA 19-9 not been found useful Barium Enema (double contrast) o Good sensitivity for cancer- 85-97%, questionable for polyps 32-60% depending on size CT Colonography o Must undergo complete bowel prep and have air/CO2 insufflated though a rectal catheter to distend the entire colon o May use barium per rectum to “tag” any residual stool in the colon Drawbacks to CT colonography o nontherapetic modality, and positive findings require intervention o No standardized protocol o Difficult to detect low rectal lesions o Pt still takes the prep Colonoscopy o considered the gold standard test for detection o considered to have the highest sensitivity and specificity o there are NO randomized controlled trials Multiple societies/ organizations have recommendations, all that differ slightly Most agree that for average risk, screening should begin at age 50 Screening ends by age 85, with a range of 7585 Method Interval Society Fecal Occult Blood Testing or FIT Yearly USPSTF, ASGE, USMSTF Fecal DNA Unspecified USMSTF Tests that detect Double Contrast Barium Enema Every 5 years USMSTF Cancer and Polyps CT Colonography Every 5 years USMSTF Flexible Sigmoidoscopy Every 5 years USPSTF, ASGE, USMSTF Flexible Colonoscopy Every 10 years USPSTF, ASGE, USMSTF Tests that detect Cancer United States Preventive Services Task Force (USPSTF), American Society of Gastrointestinal Endoscopy (ASGE) , U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) Environmental Factors Genetic Susceptibility Cancer Age/Time Diet: o High fat o Low fiber o Red meat o Low calcium o Obesity o Smoking o Physical activity Sporadic (65-85%) Familial (10-30%) Rare CRC Syndromes (<0.1%) FAP (1%) HNPCC (2-5%) Hereditary Non-Polyposis Colon Cancer 2-5% of all colorectal cancers o Lynch 1 • Colorectal cancers only o Lynch 2 • Colorectal cancers • Other cancers (Endometrial, ovarian, pancreatic, gastric, transitional cell of kidney/ureter) • Most common inherited colon cancer syndrome Amsterdam II criteria • 3 – 2 – 1 Rule – 3- family members with CRC or HNPCC associated CA (2 first degree) – 2- generations involved – 1- family member < 50 years Bethesda guidelines: o Meet Amsterdam criteria o Individuals with 2 HNPCC-related cancer o Individual with CRC and • 1st degree relative with HNPCC-related CA <45yo or • 1st degree relative with adenoma < 40yo o Individual with R-side CRC with undiff pattern <45yo o Individual with CRC or endometrial CA <45yo o Individual with signet cell CRC <45yo o Individual with adenoma <45yo Genetic testing should be considered when o Individual meets Amsterdam criteria o Individual meets Bethesda guidelines o Tumor is MSI + Pre-operative workup o Colonoscopy- evaluate for other polyps/cancers o CEA level o CT scan of chest/abd/pelvis Surgical principles o Exploration- either lap or via open techniques • Evaluate peritoneum, adjacent organs, and liver o Resection • Removal of primary lesion with “adequate” margins • Removal of the zone of lymphatic drainage- defined by arterial blood supply, resected at or near origin Laparoscopic vs. open? Literature- Laparoscopic colectomy is equivalent cancer related survival to open colectomy Benefits of laparoscopic methods for postoperative recovery Differs from colon cancer o Pelvic anatomy o Radiation therapy o Surgical treatment options Pre-op work-up o Very important, as stage effects order/components of treatment • • • • • Colonoscopy- evaluate for other polyps/cancers CEA level CT scan of chest/abd/pelvis Endorectal ultrasound or MRI Physical exam/flex sig DRE informationo Location o Position o Size o Fixed vs. mobile Endorectal ultrasound/MRI: o the most important pre-operative component • ERUS- 67-95% sensitivity for T stage • MRI (with EndoCoil) 60-95% sensitivity • Both modalities are less sensitive for N stage • Determine the need for Neoadjuvant 5FU/Radiation • Stage II and III (T3, T4, and/or N+) Before the 1970’s rectal cancer was treated with surgery alone o 1975 trial comparing surgery with chemo, XRT, or both • • • • Surgery only- 55% recurrence 46% with chemotherapy, 48% with radiation therapy 33% with combined modality o NIH Consensus Statement 1990 • Stage II and III rectal adenocarcinoma should be treated with adjuvant chemoradiotherapy At the same time- specifically in the 1990s, there became a realization that not all surgery was being performed equally o “Total mesorectal excision” Distal Mural Resection Margin o 1-2 cm o Tumors do not spread longitudinally in wall of rectum Radial Margin o Critical to ensure complete tumor removal o Pathologists must measure and report Mesorectal Margin A review of 51 surgical series showed that TME reduced the median local recurrence rate from 18.5 to 7.1%. German rectal cancer trial update 2004 n Local pelvic failure 12% Survival Anastomotic leak Toxicity (acute) Toxicity (late) Preop XRT 405 6% Postop XRT 392 No difference No difference Lower Higher Lower Higher •Shrink tumor prior to removal •Downsizing •Downstaging •Sterilize margins prior to pelvic dissection •More effective than postop XRT • oxygenated field •Better functional result •Radiate only one side of anastomosis •More patients complete treatment course Prospective, Randomized, n=1748 Pre-Op XRT vs. surgery alone (TME) Local pelvic failure (recurrence) XRT + Surgery Surgery 2.4% 8.3% 5.8% 11.4% 2 yrs 5 yrs Laparoscopic vs. open resection for rectal cancer 1 major trial, 1 underway Prospective, randomized, experienced surgeons Disease free survival and local control (3 years) • n=794 overall • n=242 rectal o No difference between laparoscopic and open o Local failure • Anterior resection • APR open 7% 21% lap 8% 15% ________________________________________________ ACASOG Z6051 Trial o American College of Surgeons Oncology Group o 650 pts, randomized, multi-center trial of open vs. HALS resection for rectal cancer Prosgood visualization o precise movements o better ergonomics o Conso hard to move from one quadrant to another o costly o lack of stapler/vessel sealing device Unless directly invaded by tumor, skeletal muscle is not at risk for tumor implantation. Therefore, there is no reason to excise the anus or levators… … if it will not improve oncologic outcome. Appropriate if tumor invades anal sphincter or levator ani Coloanal anastomosis Same dissection, but instead of removal of the anus, the colon is hand sewn to the anal mucosa Transanal Endoscopic Micro Surgery o Can do full thickness excision of rectal wall o Ideal for • • • • Unresectable adenomas Carcinoid tumors T1 rectal cancer T2 rectal cancer? In the past 3 decades significant changes in the diagnosis and treatment of colon and rectal cancer has resulted in: o Decrease in incidence o Decrease in mortality o Less invasive procedures with shorter hospital stay