Rubén Del Castillo

Radiation Oncologist

[Nick James @Prof_Nick_James]

MFS by conventional imaging identical between ENZARAD and PROTEUS at 5 y and both trials negative for addition of ARPI. This was the initial primary in PROTEUS and hard to see why should be viewed as positive. PET imaging triggered by PSA >0.2 hence PROTEUS MFS = PSA PFS

[Daniel E Spratt @DrSpratticus]

11/n #ASCO26

In summary, congrats to a large well conducted trial. Amazing team.

The take home message to me is that the addition of 1 year of ADT+Apa to RP improves BCR and EFS as expected, which can be captured in PET-based MFS which they changed their primary endpoint to include. No data has been shown with large enough effect sizes to believe this will ever translate into conventional imaging MFS, or more importantly OS signals, to make me excited about this for patients.

Does a man want 1 year of ADT/ARPI+RP and still high rates of post-op RT+ADT....when they can now simply get RT+ADT without any ARPI based on Enzarad?

@prostatemd @SbrtSean @PCF_select @urotoday @ASCO @AmarUKishan @Soum_Roy_RadOnc @CaPsurvivorship @wandering_gu @ChapinMD @SeanMcGuireMD @seanmmcbride @TylerSbrt @HimanshuNagarMD @DrPaulNguyen @DrHowardSandler @aleberlin2 @neerajaiims @ChadTangMD @DrMLChua

[Dr. Andrew Loblaw @DrAndrewLoblaw]

There are now 5 RCTs addressing the Q of ENI in high/very high risk prostate cancer (NRG 9413, 0924; GETUG-01; POP-RT and PEACE-2). Only POP-RT is positive (less than 4%) of total.

All show increase adverse events.

I think the data are clear. But debates will be inevitable

[Alison Tree 💙 @alison_tree]

Great presentation from @DrSACooper on the DESTINATION 1 trial - dose escalation to GTV and simultaneously de-escalating rest of gland appears to have similar adverse events to PACE B. Thanks to collaborators @MOMENTUM_study @dr_vesi @royalmarsdenNHS Uulke van der Heide

[Shankar Siva @_ShankarSiva]

📣@PBlanchardMD shows #ESTRO26 that pelvic #radiotherapy in high risk #prostatecancer does not have a large improve in outcomes.
- With only 1 in 10 dying of prostate cancer in 10 years, are these patients truly “high risk”? #pcsm #radonc

[Jay Detsky @jaydetsky]

Excited to share our publication in @TheLancetOncol on the primary results from the UNITED study: a new paradigm in radiotherapy for patients with glioblastoma /1 @Sunnybrook @UofTDRO https://t.co/SDon3EOlEh

[arjun sahgal @SahgalArjun]

Our @Sunnybrook innovation de-escalating the volume of normal brain tissue irradiated by 40 to 70%, for patients with #Glioblastoma, using @Elekta Unity MR Linac technology is out @TheLancetOncol. Possible only due to adapting weekly in real time using MR-guidance. Progress made!

[Rohit Malde @roxboxfix]

SBRT vs HDR Brachytherapy for Intermediate-Risk Prostate Cancer

Post hoc analysis = 5 prospective trials
247 men = Intermediate Risk Prostate Cancer [ No ADT]

SBRT had significantly lower BCF and acute genitourinary AEs, and there was no significant difference in late PR-QoL

[Dr. Andrew Loblaw @DrAndrewLoblaw]

Curious about whether #SBRT or #brachy is better treatment for intermediate risk prostate cancer?

See @cristian_udo @JAMANetworkOpen article just posted!

JAMANetworkOpen.2026;9(2):e260146. doi:10.1001/jamanetworkopen.2026.0146

@DrSpratticus @AmarUKishan @nickva1 @alison_tree

[Jay Detsky @jaydetsky]

@DrAndrewLoblaw @dr_vesi LOL. A fancy graphic with percentages of patients with serious toxicity; and this in the abstract. Also, half the patients had surgery and RT and no differentiation for late toxicity between the two, but sold as “late radiation adverse events”

[Ciro Franzese @CiroFranzese1]

@RicBertolo @EurUrolOncol @bernardorocco73 @minerviniandre @PaoloVerze @antopastl @lucacindolo @foxal72 @EAU_Uroonco @aleantonellibs1 @AgileGroupUro When specialists feel the need to build studies mainly to discredit another discipline or treatment, it often reflects a lack of confidence in their own. Medicine advances through integration, not demonization

[LARVOL @Larvol]

The 2025 edition of the Top Oncologists on 𝕏 for Radiation Oncology is here.

Selected through peer nomination and social media influence, these oncologists are the leading voices in the field.

#LARVOL #CancerResearch #CancerData #Oncology #OncologyInsights #ClinicalTrials #RadiationOncology #RadOnc | @NiuSanford | @_ShankarSiva | @DrSpratticus | @piet_ost | @alison_tree | @AmarUKishan | @drdavidpalma | @DavidSherMD | @DrAndrewLoblaw | @KrishanJethwa | @DrMLChua | @NicholasZaorsky | @SbrtSean | @imrtlee | @GeneCollector | @Larvol

[Rubén Del Castillo @RDC13ro]

Extramammary Paget's disease is a rare neoplasm that typically presents in the genital area.
In this series, we present an innovative approach using brachytherapy with custom-made 3D-printed molds. @DrAmanTaggar

[JAMA Oncology @JAMAOnc]

Meta-analysis: Among patients with intermediate-, high-, or very high-risk prostate cancer, the ideal duration of ADT with radiotherapy demonstrated nonlinear benefits, with diminished gains after 12 months and variation in benefit by risk group. https://t.co/corNHgWM5b

[Rubén Del Castillo @RDC13ro]

@weeloonong @TROGfightcancer @CDNCancerTrials @SahgalArjun Superstars ⭐️⭐️⭐️⭐️

[Dr. Andrew Loblaw @DrAndrewLoblaw]

@RDC13ro presenting active surveillance for men with low and intermediate risk #ProstateCancer
@Sunnybrook

N=1699, 18% GG2
mFU 9.4y
37% treated, 50 pts developed mets, 31 PC death
APP4 1-5% had same low risk of M1 and PCM (compared to pure GG1)

#ASTRO25

[Daniel E Spratt @DrSpratticus]

As expected people resist letting go of dogma. Lets review the common examples people grasp at:

1. Nodal field size: cited as why GETUG01 was negative (S1/S2), then cited why RTOG 9413 was negative (L5/S1), then POP-RT positive (L4/L5), but definitive trial of RTOG 0924 (L4/L5) negative

[Rubén Del Castillo @RDC13ro]

@weeloonong @NRGonc @TROGfightcancer @KHoffmanMD @DrPaulNguyen @jeremymillar @theresekang_ @Niluja5 @DavePryorRO @damien_bolton Congrats Wee!

[ISRSy @ISRSy]

ANNOUNCING: The next #ISRSWebinar 📣

“Stereotactic Radiation in Gynecological Cancers: Metastasis, Adjuvant and Definitive Treatment”

🗓️ Tues, 23 September, 2025, 4pm CET
🥼Eric Leung, MD MSc FRCPC
@leunger22

The goal of this presentation is to review the indications of stereotactic radiation in gynecological cancers and its role and treatment for metastasis , definitive local treatment and adjuvant treatment.

This important webinar is FREE when you join us Live!

👉 REGISTER: https://t.co/fv258FBw88

[Rubén Del Castillo @RDC13ro]

@DrAndrewLoblaw Two RadOnc superstars 🌟🌟