Fernand Bteich, MD, MS

@GIMedOnc What was the tumor fraction? I would repeat 2-3mo later before committing to treating if TF very low. I've seen oscillations from 0 to 0.05%.

It finally happened. A tumor-agnostic ctDNA assay came back positive. The tumor-informed assay was negative. Yes, both were sent. Let’s move on 😅 This is actually a useful reminder that ctDNA is not one thing. There are a variety of flavors, and discordant results are exactly where those differences start to matter. Tumor-informed assays 🧬 Built from the patient’s own tumor 🎯 Optimized for detecting very low levels of residual disease ⏳ Slower and requires tumor tissue Tumor-agnostic assays ⚡ Off-the-shelf and fast 🌍 Broader signal without needing tissue 👉 Useful when tissue isn’t available or when speed matters Why I paused is obvious: the data didn’t agree. The next step isn’t to pick sides between assays. It’s to step back, evaluate the patient, and remember that no test is perfect. When something comes back positive, the right move is to dig in. What, exactly, triggered the call? Variant type, allele fraction, reproducibility over time. Sometimes the answer is in the details. In this case, I had been actively considering de-escalation for an older patient. Given the uncertainty and the risk profile, we chose to treat (together). ctDNA doesn’t make decisions for us. It informs them. No single assay has all the answers 🧰 Each is a tool, and discordance is not failure, it’s information. The job is to use the right tool, for the right patient, at the right time. @OncoAlert @TheGutOncLab

HISTORIC. 22 year old Carlos Alcaraz defeats 24-time GS champ Novak Djokovic 2-6, 6-2, 6-3, 7-5 to win the #AusOpen for the 1st time and become the YOUNGEST EVER player to complete the career Grand Slam. Already one of the best players ever. What a time to be alive.

@GIMedOnc 100%

@fernandbteich This is why all CRC patients need NGS (ALASCCA a great excuse).

Young patient with locally advanced MSS/POLE P286R mutated ascending colon adenocarcinoma. Pembrolizumab started on 12/31/2025. You know the magic is happening...

@GIMedOnc DL363 representing

✈️ Heading back from #GI26 SF to NY and Delta upgraded all of us. Which means… an impromptu multidisciplinary tumor board at 35,000 feet (we may have been told to quiet down after getting a little too loud about #GI26 😅) Hepatobiliary surgery + GI medical oncology represented. Need to get rad onc and radiology here next year to really show how complex GI cancer care should happen. @patel_riya7 @sepideh_gholami

A revolution is coming. 👀 #GI26

@GIMedOnc I expect MATTERHORN to be in line with these numbers.

#GI26 NEOSUMMIT-01, now presented 🔥 Randomized Ph II perioperative oxaliplatin-based doublet (CAPEOX or SOX) ± PD-1 inhibitor toripalimab in cT3–4N+ GC/GEJC. For context: perioperative chemotherapy alone has produced only modest gains for decades, with relapse (especially peritoneal) remaining the dominant failure pattern. NEOSUMMIT-01 delivers something we have not seen before 👇 📈 3-year EFS 74.7% vs 56.2%, HR 0.51, P=0.044 📊 3-year OS 81.3% vs 72.2%, HR 0.45, P=0.036 🚫 Metastasis/relapse nearly cut in half: 18.5% vs 38.9%, P=0.019 ⏳ mEFS not reached with perioperative chemoIO vs 38.2 months with chemo alone Benefits held up in per-protocol analyses and after excluding dMMR patients. 🔥 The dramatic reduction in peritoneal relapse is the standout. CAVEAT: China only study. Unclear if results will translate to a global population. These are fantastic results and set a high bar for perioperative chemoIO in locally advanced GC/GEJC. @OncoAlert @TheGutOncLab

@GIMedOnc @ShrutiPatelMD @ASCO It's 2AM NYC time, just landed.

@ShrutiPatelMD @ASCO Way to rub it in as I sit on the tarmac at SFO.

NO AIRPORT SELFIE BEFORE @ASCO #GI26 because I live a mile from the conference center 😂 so couch selfie it is! Can’t wait to see some of my favorite people in oncology this weekend!

@jeff070 @LynnTraboulsi @BecharaGerges @RH4N6 Yes

@LynnTraboulsi @BecharaGerges Hayda ken estez histoire bi antoura. Barke 3allamne ma baaref en 2004 la sou2 el hazz. @RH4N6 @fernandbteich btetzakarou?

🚩 جنون للأسف، يستند هذا الطرح إلى فهم مغلوط لمعنى الهوية. فالهوية لا تعني الجمود ولا الانكفاء إلى الماضي، بل تعني تثبيت نفسنا في إرثنا وتقاليدنا ومعتقداتنا وثقافتنا وملامح شخصيتنا التاريخية، فيما نمدّ يدنا بثبات نحو التطوّر والتحسين والمستقبل. إن تسليم الذات بالكامل لرؤية مجرّدة عن المستقبل هو في جوهره تخلٍّ عن الأساس الذي يمكّن المجتمعات من مواجهة المجهول. فالمجتمع الذي يفقد هويته لا يصبح أكثر قدرة على التكيّف، بل يتحوّل إلى كيانٍ معلّق، بلا بوصلة ولا اتجاه. في المقابل، المجتمع المتجذّر في هويته هو وحده القادر على مواجهة التحوّلات بثقة، وعلى قراءة التغيير من خلال منظومة قيم ثابتة، وعلى توجيه مسار التقدّم بدل أن يبتلعه. من هذا المنطلق، فإن تصوير الهوية على أنها عائق أمام التقدّم ليس فقط استخفافاً فكرياً، بل طرحاً خطيراً، لا سيما حين يُسوَّق للأجيال الشابة. ولذلك، أدعو الشباب إلى التشكيك في هذه السرديات السطحية، وإلى البحث العميق، والتمييز بين التقدّم الحقيقي وبين الأفكار التي تنزع عنهم بوصلتهم التاريخية والثقافية.

@GIMedOnc Compare that to nonHER2+ disease where OS is 12-14mo. #perspective Hopefully HER2/IO therapy will find footing in the early stage setting and help cure more patients. PHERFLOT is promising.

@fernandbteich The fact that 2.5-3 years is “happy” just shows we need better therapies.

Upper GI has the blessing of multiple actionable bio-markers. Outside of MSI, none is more important than HER2. Great slide (and also includes the upcoming Zanidatamab which should redefine 1L HER2+ after approval).

Popular art references in Guillermo del Toro’s Frankenstein (2025). Del Toro pulls from classic paintings, gothic illustrations, and early expressionist cinema to shape the Creature’s look and mood. It’s a film stitched together from art history.

LBA #STELLAR303 @AnwaarSaeed3 with ⬆️ OS for the combination of Zanzalintinib plus Atezolizumab vs Regorafenib in met #colorectalcancer with HR = 0.80. ⬆️OS in EARLY interim analysis for non-liver mets of 15.9M vs. 12.8M. Published @lancet today. @ExelixisInc #CancerResearch

STELLAR-303 from Dr. Saeed, zanzalintinib+atezo vs regorafenib in MSS mCRC (>55% liver mets): OS 10.9 vs 9.4 months (HR 0.80, p=0.0045). PFS 3.7 vs 2.0 months. PR rate 4 vs 1%. #ESMO25

@GIMedOnc @FoghornRX @TheGutOncLab @OncoAlert Very exciting data

Desmoid tumors are exceptionally challenging to treat. Seems like a very interesting drug @FoghornRX is changing the game with their B-Catenin:TCF4 inhibitor. Great work... Hoping to see this in more tumor types soon. @TheGutOncLab #ESMO25 @OncoAlert

@OncoThor @myESMO Any particular studies you'd highlight?

I am clearly feeling the love for NETs at @myESMO. Several sessions dedicated to what according to some data is the second most prevalent GI cancer. If you are a GI oncologist, odds are you will be seeing NET/NEC patients so you might want to attend, either in person or on demand

@aftimosp @fedrophd @etop_ibcsg @BIGxResearch Solid work. Congrats!

“We made it!” @fedrophd presenting the updated results of POSITIVE. After 71 months of median follow-up, temporary interruption of ET for pregnancy was not associated with worse BC outcomes. Super news for patients! 👏 groups & investigators for this academic effort. #ESMO25

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