Heidi Ko

Director of Medical Affairs @Labcorp Oncology. Breast Medical Oncologist. Former Hem/Onc Fellow @MontefioreNYC. Former resident @UTHimres. Alum @UNC. #BCSM

[Heidi Ko @CancerDocKo]

Thank you @JNCCN 🙌🏼 #MedTwitter #bcsm #nccn #breastcancer

[Journal of the @NCCN @JNCCN]

Clinical Utility of 18F-FDG PET/CT in Staging Localized #BreastCancer Before Initiating Preoperative Systemic Therapy: https://t.co/qPg8N6vRyt #BCSM #radonc @CancerDocKo @CharitoLoveMD1 @jsparano

[Balazs Halmos @BalazsHalmosMD]

Congrats to Elsa- so well-deserved!
In recognition of all her great ctDNA work we should rename tissue-agnostic MRD approaches to tissue-Anagnostic ones!😉
@PGrivasMDPhD

[Paolo Tarantino @PTarantinoMD]

Not sure I had seen this before—

Kaplan-Meier curve for overall survival in SERENA-6, with a median follow up of 23.5 months and 30% maturity

[Jame Abraham, MD, FACP @jamecancerdoc]

This is a paradigm shift - future neoadjuvant ( post neaoadjuvant ) clinical trials should consider ctDNA instead of pCR !

[Paolo Tarantino @PTarantinoMD]

When I moved to the US in 2021, breast oncology was very different. With 2025 coming to an end, I decided to look back and review 10 major milestones in BC medical oncology care we saw over the past 5 years. With hope and expectation to see so much more unfolding over the next 5!

[Nicholas Hornstein @GIMedOnc]

ASCO GI is upon us.
The data leakage has begun 👀🔥

Late-breaking press release ahead of ASCO GI for HERIZON-GEA-01, testing zanidatamab + chemo, with or without tislelizumab, vs trastuzumab + chemo in first-line HER2+ locally advanced or metastatic GEA.

Important caveat up front: this is a press release, not a paper. But the signal is hard to ignore.

🧬 PFS improved in both zanidatamab arms
Median PFS 12.4 months for both doublet and triplet vs 8.1 months with trastuzumab

Roughly a 35% reduction in risk of progression

🧠 The real interest lies in OS
Triplet median OS 26.4 months vs 19.2 months with trastuzumab
That’s more than two years median OS in metastatic GEA

The doublet also crossed 24 months with a strong trend (is tisle necessary?)

🧐 Key nuance:
PFS is essentially identical between doublet and triplet
OS clearly separates
This looks like depth and durability rather than early disease control

📊 ORR is similar across arms, but duration of response is dramatically longer
DoR 20.7 months with the triplet vs 8.3 months with trastuzumab

💧 Toxicity note
Diarrhea is the standout issue and will need proactive management
Grade 3 or higher diarrhea occurred in roughly 20 to 25 percent, with overall diarrhea rates around 40 percent
Open question

I would love to see this compared head-to-head against current SoC chemo + trastuzumab + pembrolizumab. That said, it’s hard to argue with a two-year median OS and a clear survival tail.

Takeaway:
If confirmed on full presentation, zanidatamab looks poised to replace trastuzumab in first-line HER2+ GEA. The next step may not be whether it works, but how much intensity each patient really needs.

#GI26 @OncoAlert @TheGutOncLab
https://t.co/m4aJv6h5nv

[Oncology Brothers @OncBrothers]

We all will be having this conversation and cross trial comparison for every EGFR mNSCLC pt we see in the clinic. Take a minute to get a real pt perspective by @jillfeldman4 👇👇 #FLAURA2 & #MARIPOSA data!

#WCLC25 #OncTwitter #lcsm

[Balazs Halmos @BalazsHalmosMD]

Oncologists
Arriving at ASCO
Returning from ASCO

#ASCO25

[OncoDaily @oncodaily]

Excited to Share @Labcorp's Oncology Testing Solutions at @ASCO 2025 - Heidi Ko (@CancerDocKo)

https://t.co/eHUanlmqYx

#OncoDaily #Oncology #Cancer #Health #Medicine #MedTwitter #MedEd #MedOnc #MedNews #ASCO2025 #Labcorp @CancerWorldmag

[Dr. Nina Niu Sanford @NiuSanford]

There’s no Level 1 evidence that our current frequency of post-treatment surveillance imaging & labs reduces the risk of death.

(From NEJM piece on pros/cons of routine surveillance protocols, especially relevant in current ctDNA era) – worth a read!

https://t.co/usCJsBIgHI

[Cancer Discovery @CD_AACR]

Online now for the #AACR25 session on Advances in #KRAS Biology in PDAC by session speaker @andrewaguirremd: Response and Resistance to RAS inhibition in Cancer https://t.co/y2lwO3oXdz

[Paolo Tarantino @PTarantinoMD]

Evolution of HER2 testing over 40 yrs.

IHC lacks the dynamic range to predict outcomes with T-DXd, yet novel quantitative assays are emerging.

We presented data with HS-HER2 to predict T-DXd activity at #ESMO24. More data coming at #ASCO25.

Stay tuned.

https://t.co/ZcH1fAjpJd

[Rebecca Shatsky, MD @Dr_RShatsky]

PSA to cancer patients out there. Putting the word integrative in front of their name does not make a non-oncologist an oncologist. Cancer biology is incredibly complicated and takes decades to learn. If someone did not do medical oncology fellowship they are not med onc. #bcsm

[Anis Toumeh, MD @AnisToumeh]

HER2 is no longer just a breast/Upper GI cancer story. ADCs are changing the landscape, making HER2 a tissue-agnostic target across multiple tumor types. Our mini-review article in @FrontOncology on the subject. @OncoAlert

https://t.co/PQC2TPWQTn

[Dr. Nina Niu Sanford @NiuSanford]

ctDNA in CRC is prognostic, but there is no data showing that treatment initiated earlier based upon ctDNA positivity confers improved survival (or QOL).

Earlier detection alone does not equal benefit.

Great job @KristenCiombor 👏👏 #GI25

[Oncology Brothers @OncBrothers]

2024 approvals: Summary of 6 new drugs/indications in GI Malignancies by @US_FDA

1. #LiposomalIrinotecan
2. #Adagrasib
3. #Zolbetuximab
4. #Zanidatamab
5. #Zenocutuzumab
6. #Encorafenib

#gism #OncTwitter #MedTwitter #PancChat

[Heidi Ko @CancerDocKo]

I’m so honored to present this important study on patient awareness of HER2-low breast cancer, led by amazing @BeccaPrevisMD @Labcorp @outcomes4me at #SABCS24 🌟

➡️ Patient awareness gaps exist and education increases biomarker awareness and empowers pt-doc discussion

[Heidi Ko @CancerDocKo]

Annual #SABCS24 with this #SHero 🌟

@mazo_md

[Dr Sarah Sammons @drsarahsam]

As I try to figure out INAVO120, I would like to point out that patients with PIK3CA mutations do very well on first line Abema/Fulv or Ribo/Fulv with median PFS beyond 16 months in registrational trials.

Palbo/Fulv as a control arm is questionable

Thanks @Larvol for dataset.

[Paolo Tarantino @PTarantinoMD]

Node-negative subanalysis of NATALEE (n=613). Mostly includes patients with T2 disease (75%), virtually all with G2-3 disease. Consistent benefit in iDFS (93.2% vs 90.6%, HR 0.72), DDFS and DRFS with adjuvant ribociclib. Safety also consistent with ITT. #ASCO24 #bcsm

[Paolo Tarantino @PTarantinoMD]

1. 1998: the FDA approves trastuzumab. HER2+ becomes clinically relevant.

2. 2022: T-DXd improves outcomes in HER2-low MBC. HER2-low becomes clinically relevant.

3. 2024: T-DXd improves outcomes in HER2-low + ultralow. HER2-ultralow becomes clinically relevant.

4. Stay tuned