The trial’s elegant 2 × 2 factorial design addressed two independent questions simultaneously. The first randomisation, published in The Lancet, compared the four-drug PAXG regimen — cisplatin, nab-paclitaxel, capecitabine and gemcitabine — against the widely used mFOLFIRINOX combination of fluorouracil, leucovorin, irinotecan and oxaliplatin as preoperative therapy. That analysis showed PAXG produced a longer median event-free survival of 16 months versus 10.2 months, with a hazard ratio of 0.63, establishing the regimen as a new benchmark in this disease. Patients who remained free of progression or limiting toxicity after four months were then offered a second randomisation, the subject of the new analysis: whether the final two months of the same regimen should be given before surgery or reserved as adjuvant treatment after resection.

Between February 2021 and September 2024, 171 patients underwent this second randomisation, with 86 assigned to long-course and 79 to short-course preoperative chemotherapy. After central review excluded six patients found to be ineligible, the intention-to-treat population comprised 165 patients, and the final event-free survival analysis was performed after a median follow-up of 33.4 months, by which time 116 events — 70 percent of the population — had occurred. No patient was lost to follow-up, an unusually clean dataset for a trial of this size and complexity.

The primary result was unambiguous in its neutrality. Event-free survival, the prespecified primary endpoint encompassing progression, recurrence, unresectability, intraoperative metastasis detection and death, was statistically indistinguishable between the arms. The unadjusted hazard ratio comparing long-course with short-course treatment was 0.98, with a 95 percent confidence interval of 0.68 to 1.41 and a P value of 0.90. Median event-free survival was 13.0 months in the long-course group and 15.2 months in the short-course group, while three-year event-free survival rates were 27.1 percent and 23.6 percent respectively. Multivariable Cox regression confirmed the conclusion: chemotherapy duration was not associated with event-free survival after adjustment, whereas the chemotherapy regimen itself remained the only significant factor, with PAXG conferring a hazard ratio of 0.67 compared with mFOLFIRINOX.

Beneath that headline of equivalence, however, the secondary endpoints tell a more nuanced and biologically interesting story. A reduction of 50 percent or more in the tumour marker CA19-9 was achieved significantly more often with prolonged preoperative therapy, in 97 percent of evaluable patients compared with 84 percent in the short-course arm. Four complete pathological responses were observed with long-course treatment and none with short-course treatment, a borderline difference. The rate of lymph-node-negative resections was significantly higher in the long-course group, at 45 percent versus 27 percent, suggesting deeper systemic tumour clearance before the operation. Radiological partial responses were also numerically more frequent with the longer course, at 57 percent versus 47 percent.

Perhaps the most practically important finding concerns chemotherapy delivery itself. In the per-protocol population, 71 percent of patients randomised to complete all chemotherapy before surgery actually received all four planned administrations in the final phase, compared with only 51 percent of those whose last two months were deferred until after resection. Relative dose-density — the proportion of planned drug actually delivered over the final four administrations — was consistently higher across every agent in the long-course arm, with figures such as 85 percent versus 61 percent for cisplatin and 83 percent versus 54 percent for fluorouracil. The differential is almost entirely attributable to poor tolerability during the postoperative recovery period, when dose reductions and discontinuations are common. Because prior evidence has linked dose-density to overall survival in resectable pancreatic cancer, the authors argue that completing systemic therapy before surgery may be the more reliable way to deliver the full therapeutic payload.

The resection picture reinforces the message that longer preoperative therapy does not forfeit the chance of curative surgery, a concern raised by an earlier systematic review suggesting that courses of eight weeks or less yielded higher resection rates. In the CASSANDRA intention-to-treat population, 80 percent of long-course patients and 87 percent of short-course patients underwent resection, a difference that was not statistically significant. Notably, the apparent short-course advantage was concentrated among patients treated with mFOLFIRINOX, where the resection gap reached statistical significance, while the difference was negligible in the PAXG stratum — an observation the investigators interpret as evidence that more effective regimens can sustain disease control over longer preoperative periods. Concerns that prolonged neoadjuvant therapy in resectable disease simply allows tumours to progress beyond the surgeon’s reach were not supported by the data.

The trial is not without limitations, and the investigators are candid about them. The sample size for the second randomisation was constrained by the design, leaving 80 percent power only to detect large effect sizes, so smaller but clinically meaningful differences cannot be excluded. The enrolled population was necessarily selected: only patients who remained progression-free and tolerant after four months of chemotherapy could participate, limiting generalisability to all-comers. The absence of central pathological and radiological review, the inclusion of both resectable and borderline resectable disease, an upper age limit of 75 years, and the use of two different chemotherapy regimens all add interpretive complexity, although the prespecified test for a regimen-by-duration interaction was not significant. Overall survival data are also immature: with only 44 percent of deaths accrued so far, median survival was 50.5 months in the long-course arm versus 35.1 months in the short-course arm, a non-significant difference with three-year survival rates of 56.8 percent and 46.6 percent respectively — figures that, if they hold, would represent a striking improvement over historical benchmarks.

Taken together, the results reframe rather than resolve the question of neoadjuvant duration. The trial’s authors conclude that six months of preoperative chemotherapy achieves results comparable to four months before surgery with two months after, and that the choice to prolong preoperative treatment beyond four months can reasonably be personalised according to clinical circumstances, tumour biology and patient preference. PAXG emerges as the preferred backbone regimen in this setting, and patients who progress during the final two months of preoperative therapy may be spared a major operation unlikely to benefit them. The deeper biochemical, radiological and pathological responses seen with longer treatment hint at improved systemic clearance of micrometastatic disease, even if that has not yet translated into event-free or overall survival gains. What is clear is that the era of assuming a single fixed duration of preoperative therapy for all patients with operable pancreatic cancer is over, and future research must now turn toward more effective drug regimens and better tools for selecting which patients truly benefit from surgery.

Subject of Research: Optimal duration of neoadjuvant chemotherapy before surgery in resectable and borderline resectable pancreatic ductal adenocarcinoma

Article Title: Short-term versus long-course neoadjuvant chemotherapy for resectable and borderline resectable pancreatic ductal adenocarcinoma (PACT-21 CASSANDRA): results from the second randomisation analysis of a randomised, open-label, 2 × 2 factorial phase 3 trial

Article References: Reni, M., Orsi, G., Carconi, C., Malleo, G., Procaccio, L., Macchini, M., Bencardino, K., Merelli, B., Pretta, A., Rapposelli, I. G., Pecorelli, N., Partelli, S., Sperti, E., Crippa, S., Liscia, N., Di Marco, M., Milella, M., Lonardi, S., Palumbo, D., … Falconi, M. (2026). Short-term versus long-course neoadjuvant chemotherapy for resectable and borderline resectable pancreatic ductal adenocarcinoma (PACT-21 CASSANDRA): results from the second randomisation analysis of a randomised, open-label, 2 × 2 factorial phase 3 trial. eClinicalMedicine, 99, Article 104190. https://doi.org/10.1016/j.eclinm.2026.104190

Image Credits: AI Generated

DOI: 10.1016/j.eclinm.2026.104190

Keywords: pancreatic cancer, neoadjuvant chemotherapy, phase 3 trial, PAXG, mFOLFIRINOX, event-free survival, CA19-9, surgical resection, dose-density, PACT-21 CASSANDRA, Short-term, versus

Triple-negative breast cancer, defined by the absence of estrogen receptor and progesterone receptor expression and the lack of HER2 amplification, accounts for roughly 10 to 15 percent of all breast cancers but carries a disproportionate share of early recurrences and deaths. Because the tumor lacks the molecular targets that make other breast cancer subtypes vulnerable to endocrine therapy or HER2-directed drugs, cytotoxic chemotherapy has remained the backbone of treatment. Historically, anthracycline-and-taxane regimens have been the standard of care, producing pathologic complete response rates of roughly 37 to 41 percent. When patients achieve a pathologic complete response, meaning no residual invasive cancer is found in the breast or lymph nodes at the time of surgery, their five-year event-free survival approaches 90 percent, compared with 57 percent for those who do not. That makes the response a powerful surrogate for cure and a critical endpoint for evaluating treatment strategies.

The trouble with anthracyclines lies in what they leave behind. Pooled data from randomized controlled trials show that patients treated with anthracycline-containing regimens face more than a five-fold higher risk of clinical cardiotoxicity, as well as sharply elevated risks of acute myeloid leukemia and myelodysplastic syndrome. Long-term follow-up studies in breast cancer survivors have documented heart failure, arrhythmias, and secondary blood cancers years or decades after the original diagnosis. For young women facing the prospect of decades of survival after successful breast cancer treatment, these late effects are not trivial side effects; they are life-altering or life-shortening complications in their own right. Reducing or eliminating anthracycline exposure without sacrificing cancer control has therefore become one of the most consequential questions in early breast cancer management.

At the same time, the treatment landscape has been transformed by two major developments. The first is the incorporation of carboplatin, a platinum chemotherapy agent, into neoadjuvant regimens. Trials such as GeparSixto, CALGB 40603, and BrighTNess demonstrated that adding carboplatin increases pathologic complete response rates in triple-negative disease, although often at the cost of substantially more hematologic toxicity, treatment delays, and dose reductions. The second development is immunotherapy. The landmark KEYNOTE-522 trial established perioperative pembrolizumab, an antibody that blocks the PD-1 immune checkpoint, combined with neoadjuvant chemotherapy as the new standard of care for stage II and III disease, improving both pathologic complete response and overall survival. Yet real-world experience with that regimen has revealed higher-than-anticipated immune-related adverse events, frequent discontinuation, and dose reductions, raising concerns about how much drug burden patients can realistically tolerate.

Against this shifting backdrop, a research team led by investigators at the University of Iowa and the University of Wisconsin, working with the Greater Plains Collaborative, a PCORnet clinical research network spanning ten medical centers across nine states, asked a deceptively simple question: in actual clinical practice, does adding anthracyclines to carboplatin plus taxane chemotherapy improve outcomes? They compared two regimens among women with stage I to III triple-negative breast cancer diagnosed between 2012 and 2024. The first, abbreviated CbT, consisted of carboplatin plus a taxane. The second, AC-CbT, added doxorubicin plus cyclophosphamide, the classic anthracycline combination. The primary outcome was pathologic complete response as recorded in hospital cancer registries by treating physicians, supplemented where necessary by comparisons of pre-treatment clinical staging and post-surgical pathologic staging.

The results were striking in their clarity. Among the 878 women analyzed, 41.2 percent received the anthracycline-free CbT regimen and 58.8 percent received AC-CbT. Half of the entire cohort achieved a pathologic complete response. On the surface, the anthracycline group appeared to fare slightly better, with response rates of 51.9 percent versus 47.2 percent for CbT, but this difference was not statistically significant. More importantly, after multivariable adjustment using inverse probability weighting, accounting for age, stage, grade, race, body mass index, comorbidity, treatment site, and pembrolizumab use, the addition of anthracyclines conferred no meaningful advantage, with an adjusted odds ratio of 1.05 and a confidence interval spanning 0.69 to 1.59. Sensitivity analyses that reclassified ambiguous response data or excluded those cases entirely produced the same conclusion.

What did predict response? Pembrolizumab use nearly doubled the odds of pathologic complete response, with an adjusted odds ratio of 1.97. Higher-grade tumors were more likely to respond, paradoxically, with grade 3 disease carrying nearly twice the odds of grade 1 or 2 tumors, a pattern consistent with the principle that the most biologically aggressive cancers are often the most sensitive to chemotherapy. Lower stage predicted higher response, as expected, and women diagnosed between ages 40 and 49 were roughly twice as likely to respond as those diagnosed at 60 or older, a finding the investigators probed extensively with post hoc and machine-learning analyses without uncovering an obvious explanation. Notably, an interaction analysis showed no evidence that anthracyclines mattered more or less depending on whether pembrolizumab was given, suggesting the anthracycline question remains unresolved in both the immunotherapy era and outside it.

The study also documents a dramatic practice transformation. Among all 2,413 triple-negative breast cancer patients in the underlying dataset, use of any carboplatin-containing regimen rose from 7.1 percent in 2012 to 72.8 percent in 2024. Pembrolizumab uptake was swift following the 2021 publication of KEYNOTE-522 results, and by the end of the study period, 46 percent of the analytic cohort had received it, concentrated overwhelmingly in the anthracycline-containing group. Interestingly, the data reveal how oncologists tailor care in the real world: older patients and those with comorbidities were more likely to forgo anthracyclines, while those with stage III, more aggressive disease were more likely to receive all four cytotoxic drug classes. Nearly a third of patients received combinations that had never appeared in clinical guidelines, reflecting deliberate individualized risk-benefit balancing rather than rigid protocol adherence.

Perhaps most provocative is the finding that carboplatin has penetrated into stage I disease, a population excluded from KEYNOTE-522 and still recommended anthracycline-taxane therapy by National Comprehensive Cancer Network guidelines. Among all stage I patients in the dataset, 19.4 percent received carboplatin, rising from 3.4 percent in 2012 to 41.7 percent in 2024. Within the analytic cohort, stage I patients showed similar response rates with or without anthracyclines. This off-guideline adoption finds precedent in the adjuvant PATTERN trial, in which carboplatin plus paclitaxel matched anthracycline-based therapy in five-year overall survival, with three-quarters of enrolled patients having node-negative disease.

The investigators are careful to acknowledge limitations. As an observational study relying on electronic health records and registry data, it cannot exclude unmeasured confounding, and variables such as performance status, BRCA mutation status, treatment toxicity, adherence, and relative dose intensity were unavailable. Lower delivered doses in the four-drug regimen could theoretically explain the lack of anthracycline benefit, although the authors argue that real-world tolerability is itself a legitimate measure of a regimen’s worth. The cohort also lacked racial diversity, and a notable fraction of responses were classified as “not otherwise specified,” though sensitivity analyses confirmed the robustness of the central finding.

Even with those caveats, the study represents, to the authors’ knowledge, the largest real-world analysis of triple-negative breast cancer spanning the immunotherapy era, and it provides the strongest real-world evidence yet that anthracyclines may not earn their place alongside carboplatin-based chemoimmunotherapy. Ongoing randomized trials, most notably the SCARLET trial evaluating anthracycline-free chemoimmunotherapy against the full KEYNOTE-522 regimen, will determine whether anthracycline omission can be definitively declared noninferior. Until then, this research shifts the burden of proof: the question is no longer whether patients can safely be spared anthracyclines, but whether the drugs still have anything left to offer.

Subject of Research: Anthracycline-containing versus anthracycline-free carboplatin-based regimens in early-stage triple-negative breast cancer: real-world outcomes

Article Title: Anthracycline-containing versus anthracycline-free carboplatin-based regimens in early-stage triple-negative breast cancer: real-world outcomes

Article References: Kroll, M. R., Schroeder, M. C., Neuner, J. M., Viyyuri, B. R., Ravindra, A., McDougall, D., Chapman, C. G., Fleege, N. M. G., Chrischilles, E. A., Song, X., & Phadke, S. (2026). Anthracycline-containing versus anthracycline-free carboplatin-based regimens in early-stage triple-negative breast cancer: real-world outcomes. Breast Cancer Research and Treatment, 219(2), Article 7. https://doi.org/10.1007/s10549-026-08071-8

Image Credits: AI Generated

DOI: 10.1007/s10549-026-08071-8

Keywords: Anthracycline-containing, versus, anthracycline-free, carboplatin-based, regimens, early-stage, triple-negative, breast, cancer, real-world, outcomes, scientific research

The magnitude of the time saving reported in the trial is striking. A mean venous anastomotic time of 8.1 minutes in the coupler group versus 19.2 minutes in the hand-sewn group represents a reduction of more than eleven minutes per venous repair, with a confidence interval indicating that the true saving lies between roughly ten and twelve minutes. In reconstructive procedures that often last several hours, this saving may appear modest, but its cumulative effect can be substantial. Shorter operative times are associated with reduced anesthesia exposure, lower costs, and potentially decreased risks of infection, thromboembolic events, and other perioperative complications, particularly in elderly patients or those with significant comorbidities undergoing lengthy oncologic reconstructions.

The mechanism by which the coupler achieves speed is worth understanding. The ring-pin device consists of two polyethylene rings with intraluminal pins; the vessel ends are passed through the rings and everted over the pins, which are then telescoped together. This produces an immediate, circumferential, intima-to-intima approximation without any suture material exposed to the bloodstream. By contrast, a hand-sewn anastomosis requires multiple interrupted sutures, each of which passes through the vessel wall and temporarily disrupts flow, creating opportunities for endothelial injury, mural thrombus formation, and turbulence. The theoretical hemodynamic advantage of the coupler, namely laminar flow across a smooth synthetic scaffold, has been supported by experimental studies of flow dynamics, although the clinical trial found no statistically significant difference in thrombosis rates between the techniques.

The reported thrombosis figures, 2.9 percent in the coupler group and 5.7 percent in the hand-sewn group, are consistent with the range of venous thrombosis rates reported across the broader microsurgical literature. The failure of this difference to reach statistical significance, with a p value of 0.68, should be interpreted cautiously. With seventy patients per arm, the trial was powered to detect a difference in anastomotic time, not in thrombosis or flap survival. Detecting a reliable difference in an event occurring at a rate of a few percent would require thousands of patients per group, as the authors themselves acknowledge. The absence of a statistically significant difference is therefore not evidence of equivalence, and clinicians should understand the trial as demonstrating a robust time advantage while leaving safety outcomes unresolved at the level of proof.

Complete flap survival exceeded 95 percent in both arms, reaffirming the overall reliability of contemporary free-tissue transfer. Success rates above 95 percent have become the expected standard in high-volume microsurgical units, and both techniques in this trial met that benchmark. The near-identical survival figures, 97.1 percent versus 95.7 percent, mirror the findings of prior systematic reviews and meta-analyses, which have generally concluded that coupler patency is at least comparable to hand-sewn patency in the venous circulation. Notably, the coupler has historically been considered less suitable for arterial anastomoses, particularly in smaller or thicker-walled arteries, which is why arterial repair remained hand-sewn throughout this study and why the findings apply specifically to the venous side of the microvascular circuit.

The observation that dual venous drainage was employed more frequently in the coupler group, 32.9 percent versus 18.6 percent, offers an interesting window into surgical decision-making. When a second venous anastomosis can be completed in approximately eight minutes rather than nearly twenty, surgeons may be more willing to invest in a second drainage pathway, particularly in flap types known to be vulnerable to venous congestion, such as those with large surface areas, deep inferior epigastric perforator flaps, or flaps draining into a single comitant vein. Although this difference did not reach statistical significance, it raises the possibility that the coupler changes not only how venous anastomoses are performed but how many are performed, a behavioral effect that could itself influence flap outcomes in ways the trial was not designed to detect.

The trial’s population spanned oncologic, traumatic, and infective indications across multiple anatomical sites, addressing a recognized gap in the literature, where much of the earlier evidence came from single-region series dominated by breast or head and neck reconstruction. This breadth improves the generalizability of the time-saving finding, since the coupler’s advantage in anastomotic speed is unlikely to be confined to one flap type. Nevertheless, the exclusion criteria, which barred severely irradiated recipient vessels, documented coagulopathy, advanced peripheral vascular disease, and poorly controlled diabetes, mean that the results apply to a relatively favorable vascular substrate. Whether the coupler performs equally well in calcified, irradiated, or friable veins, where hand-sewn repair allows more adaptive placement of sutures, remains an open question.

The requirement for recipient veins between 1 and 4 mm in diameter reflects the design limits of commercially available coupler sizes. Within this range, the device offers a standardized solution, but vessels outside it, whether exceptionally small calibre veins in pediatric or distal extremity reconstruction or larger veins in some trunk and breast reconstructions, fall outside the device’s scope. Surgeons adopting the technique must therefore maintain proficiency in hand-sewn repair as a fallback. The trial’s finding that no device-related mechanical failures occurred is reassuring, but mechanical failure of couplers, including ring fracture, pin dislodgement, and tearing of the everted vessel wall, has been described elsewhere and typically demands conversion to a hand-sewn anastomosis under time pressure.

The learning curve associated with each technique is another consideration. All anastomoses in the trial were performed by three consultant microsurgeons, each with more than five years of hand-sewn experience and more than two years of coupler experience, and each proficient in both methods. This deliberate standardization of operator expertise minimizes the confounding that has plagued observational comparisons, where coupler use often clusters among surgeons or units with particular case mixes. In less experienced hands, the coupler’s advantage may be even greater, because the device reduces the technical variability that disproportionately affects trainees; conversely, improper sizing or awkward vessel orientation can produce coupler-specific complications that careful hand-sewn technique would avoid.

The trial’s limitations merit transparent acknowledgment. Beyond the absence of prospective registry registration, which the authors themselves flag, the study employed per-protocol analysis after four post-randomization exclusions, a choice that preserves the integrity of the comparison between actual techniques but slightly weakens the intention-to-treat principle that guards against attrition bias in randomized trials. Because the excluded patients did not receive either intervention, the risk of bias here is likely small, but readers should recognize the distinction. Blinding was necessarily incomplete: surgeons could not be masked, patients were unaware of the technique, and blinded independent assessors evaluated postoperative outcomes, an arrangement that represents a reasonable compromise given the physical nature of the intervention.

From a health-systems perspective, the economic implications of an eleven-minute saving per venous anastomosis deserve attention. Operating theatre time is among the most expensive resources in surgical care, and microsurgical cases occupy theatres for extended periods. If the coupler shortens procedures without compromising outcomes, the cumulative savings across a high-volume reconstructive service could offset device costs, although a formal cost-effectiveness analysis would need to account for device pricing, failure and conversion rates, and the value of reclaimed theatre capacity. Such analyses remain scarce in the reconstructive literature and would be a natural next step for health services researchers.

The trial also contributes to a longer historical arc. Vascular coupling was first described by Nakayama and colleagues in 1962, and the modern ring-pin system refined that concept into a practical instrument. Yet adoption has been uneven across the international microsurgical community, with some units using couplers for nearly all venous anastomoses and others reserving them for selected cases or avoiding them entirely. Prospective randomized evidence of the kind now provided has been the missing ingredient in debates that have until now rested largely on retrospective series, registry data, and meta-analyses of heterogeneous observational studies.

For practicing reconstructive surgeons, the practical takeaway is nuanced. The coupler reliably shortens venous anastomosis, and no signal of harm emerged in this trial, but the study cannot exclude small differences in thrombosis or flap survival that only very large samples could detect. Surgeons should therefore weigh the time advantage against case-specific factors: vessel caliber and quality, the availability of appropriately sized couplers, the presence of size mismatch, surgeon experience, and the hemodynamic demands of the particular flap. In flaps at high risk of venous congestion, the ease of adding a second coupler-based drainage anastomosis may itself be a decisive advantage.

Future research directions follow naturally from this work. Multicenter randomized trials with large samples, or prospective registries with risk adjustment, could resolve the residual uncertainty around thrombosis and survival outcomes. Studies stratifying results by flap type, recipient site, vessel caliber, and radiation status would refine patient selection. Investigations into the hemodynamic behavior of coupled versus sewn anastomoses using intraoperative flow measurement or Doppler surveillance could clarify the mechanistic basis of any clinical differences. Until such evidence accumulates, this trial stands as the strongest prospective support to date for a simple proposition: that venous coupling is a practical, efficient, and apparently safe option for reducing operative time in free-flap reconstruction, provided surgeons retain the hand-sewn skills that remain the foundation of microvascular practice.

Subject of Research: Efficacy of venous coupler versus hand-sewn venous anastomosis in free-flap reconstruction: a single-centre randomized controlled trial

Article Title: Efficacy of venous coupler versus hand-sewn venous anastomosis in free-flap reconstruction: a single-centre randomized controlled trial

Article References: Haq, A., Singh, V. K., Sharma, S., Bhavana, K., Kumar, S., & Vishwadeep (2026). Efficacy of venous coupler versus hand-sewn venous anastomosis in free-flap reconstruction: a single-centre randomized controlled trial. BMC Plastic and Reconstructive Surgery, 2(1), Article 23. https://doi.org/10.1186/s44452-026-00036-6

Image Credits: AI Generated

DOI: 10.1186/s44452-026-00036-6

Keywords: Efficacy, venous, coupler, versus, hand-sewn, anastomosis, free-flap, reconstruction, single-centre, randomized, controlled, trial