Mark Lewis, MD, FASCO (@marklewismd) ranks #8 among US gi cancer KOLs on X in 2026, by engagement from fellow physicians. 29 physicians shared, quoted or replied to their posts this year. Most-discussed trials in 2026: HERIZON-GEA-01, RASolute 302, CIRCULATE. CMS Open Payments lists $49,420 in 2025 general payments.
At a Glance
- 6 posts naming a trial in 2026
- 5 trials discussed by name
- GI Cancer: US #8 · 29 physicians engaged
- Leading physician voice: #3 of 5 physicians on CIRCULATE
- CMS Open Payments lists $49,420 in 2025 general payments.
This Month
What Mark Lewis, MD, FASCO has posted in the last 30 days. Updated November 10, 2026.
No trial posts in the last 30 days.
Who Amplifies Mark Lewis, MD, FASCO
Physicians who reposted Mark Lewis, MD, FASCO’s trial posts most often in 2026.
2026 Rankings
| List | US rank | Global rank | Physicians engaged | Physician engagements | |
|---|---|---|---|---|---|
| GI Cancer | #8 | — | 29 | 33 | Full ranking |
What Colleagues Are Saying About Mark Lewis, MD, FASCO
2026 posts by fellow physicians that mention @marklewismd, quoted word for word.
Highlight of #ASCO26 was being able to share a stage with these giants of GI Oncology that I’ve looked up to and respected for years. Thanks to @YJanjigianMD @marklewismd and @Sarbaji85064063 for joining and making this a great event. @Onco_Nexus @TheGutOncLab https://t.co/2f5I8xtdqo
Trials Mark Lewis, MD, FASCO Discussed in 2026
| Trial | Posts | Rank among physicians posting | Latest |
|---|---|---|---|
| HERIZON-GEA-01 | 2 | #18 of 34 | Jan 8, 2026 |
| RASolute 302 | 1 | #11 of 73 | May 31, 2026 |
| CIRCULATE | 1 | #3 of 5 | May 31, 2026 |
| KEYNOTE-937 | 1 | #7 of 12 | Jan 9, 2026 |
| ILUSTRO | 1 | #9 of 11 | Jan 8, 2026 |
Mark Lewis, MD, FASCO on HERIZON-GEA-01
Dr Daniel Lin @JeffersonUniv summarizes contemporary biomarker-driven management of metastatic gastroesophageal cancer, highlighting added insights from ILUSTRO and HERIZON-GEA-01 #GI26 https://t.co/FqmdFmg0w9
HERIZON-GEA-01 shows PFS benefit for zanidatamab (bispecific anti-her2) + tislelizumab (anti-PD1) + chemo (vs. trastuzumab + chemo) for mGE her2+ cancer #GI26 https://t.co/LhlzkxtGqV
Mark Lewis, MD, FASCO on RASolute 302
Cheers, chills, and a standing ovation when RASolute 302 showed unprecedented survival on daraxonrasib for patients with progressive pancreatic cancer Seldom do you sense you’re witnessing a historic moment in cancer care but this feels like ras targeting has arrived #ASCO26 https://t.co/yS9E5kGHs1
Mark Lewis, MD, FASCO on CIRCULATE
ctDNA can clarify the personal benefit of adjuvant chemotherapy, here in stage II colon cancer (from CIRCULATE, LBA3500) Post-op + doesn't mean recurrence is inevitable, and we can be selective in which patients stand to benefit (doubling 3y DFS rates with cape alone!) #ASCO26 https://t.co/HQHsxSebgD
Mark Lewis, MD, FASCO on KEYNOTE-937
Negative trials matter too! Especially given the paradigm shift towards IO in HCC since 2020, it is important (if disappointing) to learn that adjuvant pembrolizumab does not affect survival outcomes per KEYNOTE-937 #GI26 https://t.co/HHrxMNZlnw
Mark Lewis, MD, FASCO on ILUSTRO
Phase II ILUSTRO data suggest that claudin 18.2 targeting (zolbetuximab) and immunotherapy (nivolumab) don't have to be either/or in metastatic GEJ adenocarcinoma #GI26 https://t.co/q9jbwch2Gy
Mark Lewis, MD, FASCO’s Most-Engaged Posts in 2026
Their own 2026 posts that fellow physicians reposted most, quoted word for word.
Updated analysis of CheckMate 9DW shows mOS ~ 2 years, ~30% of patients alive at 4 years with ipi/nivo (a remarkable milestone in unresectable HCC!) #GI26 https://t.co/zqgNn4Mt1i
Biliary tract cancer is arguably the GI primary site par excellence for NGS surfacing actionable mutations Lirafugratinib adds another arrow to our FGFR2-targeting quiver (but different toxicity profile -- ⬆️stomatitis, HFS -- for selective inhibition vs. pan-FGFRi) #GI26
I was a freshman in high school when I decided I wanted to be an oncologist I had a meaningful full-circle moment today at #ASCO26 when I met a remarkably articulate young man who, at roughly the same age, has set his sights on joining our field The future is so very bright🌟 https://t.co/yfgOt6yxwd
We need a lot more of these ribbons #ASCO26 https://t.co/2TQqrBFcoc
Industry Payments
CMS Open Payments · 2025 general payments
$49,420 across 52 payments