Clinical Programs Update

Our advanced endoscopy and endoscopy surgery practice is truly thriving. The Advanced Endoscopy and Endoscopic Surgery group has grown to 11 physicians and 1 Advanced Practice Provider. We perform a high volume of all advanced endoscopy cases and we are one of the highest volume centers for endoscopic surgery/3^rd space endoscopy cases in the country, which has allowed us to formally establish a fellowship training program for this emerging field. We actively collaborate with our surgical and interventional radiology colleagues to determine the optimal approach to address complex medical and surgical conditions.

ERCP: 1234

Endoscopic Ultrasound (EUS): 1132
EUS-guided AXIOS placement - 64

Per-oral Endoscopic Myotomy (POEM) - 109

Endoscopic Submucosal Dissection (ESD) - 193

Transoral Incisionless Fundoplication (TIF) - 14

Endoscopic suturing (as primary indication) - 55

Margaret Zhou who has a clinical focus in the diagnosis and management of Barrett’s esophagus in addition to advanced endoscopy (ERCP and EUS). 

Pradeep Siddappa who has a clinical focus in pancreatic diseases (acute and chronic pancreatitis) in addition of advanced endoscopy (ERCP and EUS).

Andrew Li is the first graduate of our Endoscopic Surgery/3rd Space Endoscopy fellowship program at Stanford. Andrew completed our advanced endoscopy fellowship program in 2023. He will be performing ESD, POEM, and other endoscopic surgical procedures in addition to advanced endoscopy (ERCP and EUS).

Mike Wei joined the faculty last year and performs ESD and TIF.

Aileen Bui recently completed her general GI fellowship from the University of Southern California in Los Angeles.

 Daud Akhtar recently completed his general GI fellowship at the University of British Columbia in Vancouver, Canada.

The Food and Drug Administration (FDA) has approved Guardant Health’s Shield blood test for colorectal cancer (CRC) screening in adults 45 years of age and older who are at average risk for CRC. The test works by detecting cell-free DNA (cfDNA) shed by tumors into the bloodstream, looking for specific genomic markers associated with colorectal cancer.  Here is a summary of how I interpret this approval in the context of CRC screening-

• Guardant Shield has 83% sensitivity for CRC (88% for Stages I-III; 65% for Stage I), 10% false positive rate, and 13% positivity rate for advanced pre-cancerous polyps (i.e. it does not really detect these polyps at a meaningful rate – the positivity rate for these polyps is almost the same as the false positive rate [mostly occasional “chance” detection]).

¤The FDA label (see below) includes the PRECAUTION: “Based on data from clinical studies, Shield has limited detection (55%-65%) of Stage I colorectal cancer and does not detect 87% of precancerous lesions. One out of 10 patients with a negative Shield result may have a precancer that would have been detected by a screening colonoscopy. Shield demonstrated high detection of Stages II, III, and IV colorectal cancer.”

• CMS will cover this test every 3 years based on its previously published Coverage Determination.
• Cost may change over time.
• As a one-time test, the fecal immunochemical test (FIT) has somewhat lower CRC sensitivity (74%), but higher sensitivity for advanced pre-cancerous polyps (24%), and lower false positive rate (5%) than Guardant Shield.
• In programmatic use over time, FIT yearly is believed to perform better than a multi-target stool DNA test (Cologuard) and Guardant Shield every 3 years.
• Cologuard has better detection rates for CRC (92%) and advanced pre-cancerous polyps (42%), and similar false positive rate (13%) compared to Guardant Shield.  It is recommended every 3 years.
• Modeling studies estimate the following long-term impact on CRC incidence and mortality for people who adhere with screening over time:

Putting it all together at the population level:

o   Guardant Shield is expected to have substantial net benefit if it extends CRC screening to persons who are unwilling or unable to undergo screening colonoscopy or stool-based screening.

o   However, if Guardant Shield were to substitute for screening colonoscopy or stool-based screening in those willing to use them (i.e. if it moved patients away from these options, and towards Guardant Shield), this is expected to worsen outcomes (i.e. net harm = more CRC cases and more CRC deaths).

o   Rule of thumb: for every 3 people who would be open to colonoscopy or stool-based screening who instead substitute Guardant Shield (due to convenience, etc.), >=2 other people who consistently refuse colonoscopy or stool-based screening must take up Guardant Shield (with follow-up colonoscopy if Guardant Shield result is abnormal) in order to reduce CRC mortality in the population from its current level. 

References

1. Lieberman DA; AGA CRC Workshop Panel. Commentary: Liquid Biopsy for Average-Risk Colorectal Cancer Screening. Clin Gastroenterol Hepatol. 2024 Jun;22(6):1160-1164.e1. doi: 10.1016/j.cgh.2024.01.034. Epub 2024 Mar 26. PMID: 38552672; PMCID: PMC11265647.
   
2. Ladabaum U, Mannalithara A, Weng Y, Schoen RE, Dominitz JA, Desai M, Lieberman D. Comparative Effectiveness and Cost-Effectiveness of Colorectal Cancer Screening With Blood-Based Biomarkers (Liquid Biopsy) vs Fecal Tests or Colonoscopy. Gastroenterology. 2024 Jul;167(2):378-391. doi: 10.1053/j.gastro.2024.03.011. Epub 2024 Mar 26. PMID: 38552670.
3. van den Puttelaar R, Nascimento de Lima P, Knudsen AB, Rutter CM, Kuntz KM, de Jonge L, Escudero FA, Lieberman D, Zauber AG, Hahn AI, Inadomi JM, Lansdorp- Vogelaar I. Effectiveness and Cost-Effectiveness of Colorectal Cancer Screening With a Blood Test That Meets the Centers for Medicare & Medicaid Services Coverage Decision. Gastroenterology. 2024 Jul;167(2):368-377. doi: 10.1053/j.gastro.2024.02.012. Epub 2024 Mar 26. PMID: 38552671; PMCID: PMC11193618.
4. Imperiale TF, Ransohoff DF, Itzkowitz SH, Levin TR, Lavin P, Lidgard GP, Ahlquist DA, Berger BM. Multitarget stool DNA testing for colorectal-cancer screening. N Engl J Med. 2014 Apr 3;370(14):1287 97. doi: 10.1056/NEJMoa1311194. Epub 2014 Mar 19. PMID: 24645800.
5. Chung DC, Gray DM 2nd, Singh H, Issaka RB, Raymond VM, Eagle C, Hu S, Chudova DI, Talasaz A, Greenson JK, Sinicrope FA, Gupta S, Grady WM. A Cell-free DNA Blood-Based Test for Colorectal Cancer Screening. N Engl J Med. 2024 Mar 14;390(11):973-983. doi: 10.1056/NEJMoa2304714. PMID: 38477985.

The liver transplant program at Stanford continues to excel with 134 liver transplants performed in 2023, a record number for Stanford. Moreover, the increase in volume has been accompanied by an improved transplant rate (58.4%) and amongst adult liver transplant programs in northern California, Stanford has the highest deceased donor transplant rate.  This measurement also has the largest impact on survival after listing. In addition, Stanford's observed organ acceptance is significantly higher than expected. These accomplishments have translated into a significant reduction in median wait time to transplant with our current median wait time being the shortest of all liver transplant programs in northern California (13.4 months).  In addition to the record number of transplant performed, our survival also continues to improve. Our 1 year graft (94.87%) and patient (93.36%) survival outcomes are higher than expected and higher than the national average and   results for 3-year patient survival are nearly identical to our 1 year patient survival (93.23%) and substantially higher than the national 3-year patient survival rate (89.89%,  https://optn.transplant.hrsa.gov/data/view-data-reports/center-data/).    With the addition of 5 new transplant hepatologists we are able to rapidly see patients who require evaluation for liver transplantation for cirrhosis, refractory alcoholic hepatitis, and hepatocellular cancer. 

To schedule a patient for liver transplant evaluation, you may call 650-498-7878. We also see transplant patients in our outreach clinics which you refer to below in locations across California including Pleasanton, Fresno, San Jose, Santa Maria, San Luis Obispo, and Turlock.   If your patient needs an urgent appointment, we will see your patients within 48 hours by calling (need phone number). For inpatient transfers such as acute liver failure or refractory alcohol-associated hepatitis or other end stage liver disease referrals that require inpatient transfer, you may call 650-723-4696 and ask for the hepatologist on-call.

If you are outside of Stanford Health Care, there are several ways to refer your patients. Please visit our website for links and details: https://stanfordhealthcare.org/medical-clinics/ digestive-health-center.html.

1) Refer electronically through our online portal PRISM (Physician Referral Information at Stanford Medicine). https://prism.stanfordhealthcare.org/prism/login/PRISM_User_FAQ.pdf

2) Fax referrals. From the website, you can scroll down to the section “How To Refer”, download the form and fax your request to (650)320-9443.