onc brain

The longer read

The value of this series is less the headline control rate than the failure map. A local failure-free rate of 90% at 2 years sits comfortably beside the 11% SCC local failure figure from the Mazeron experience the authors cite, so the result does not move the established view that RT is an effective definitive option for nasal skin SCC. What it adds is where control is lost. Six of ten local failures were on the bridge, and three of four bridge recurrences after a complete response had a marginal component, while two of five columella lesions failed. The authors read this as underestimation of tumor extent on curved surfaces and along embryonic fusion planes, a plausible mechanism that argues for generous margins and careful attention to dose fall-off where source-to-surface distance changes over the nasal contour.

The nodal finding is the second actionable point. Apart from one patient, nobody received intentional nodal coverage, and only 2 of 93 clinically node-negative patients failed regionally, with no adverse primary feature predicting it. That supports surveillance rather than elective nodal RT for cN0 disease, with the caveat that small numbers and short follow-up limit how much reassurance an absence of events can provide.

Confidence should be tempered in three directions. First, this is a retrospective chart review in which dose was chosen by lesion size, depth and patient frailty, so any attempt to infer dose-response is confounded by indication; the null univariate analysis with ten local events says more about power than biology. Second, the toxicity claim is weaker than the abstract suggests: late effects were not formally scored, so the absence of G4 events means none were documented, not that they were systematically sought, and cosmesis by schedule could not be assessed. Third, median follow-up in survivors was 2.9 years, and with 5-year OS of 51% in an elderly cohort, competing mortality thins the population in whom late local failure or late cartilage toxicity could surface. The 96% cause-specific survival largely reflects that patients die of other causes.

The treatment era also matters for transfer. Most patients were treated with orthovoltage selected by lesion thickness, a technique still in use but now often replaced by electrons with bolus or brachytherapy molds, which carry different surface and depth dosimetry on the nose. The authors' own shift toward 50 Gy in 20 fractions, or 60 Gy in 30 for large infiltrative lesions, is driven by cosmesis rather than control, and their observation that elderly patients often accept a 1-2 week course with a cosmetic penalty frames the real decision: schedule length against appearance, not against local control.

The series would be wrong to lean on if bridge and columella failures reflected selection of larger or neglected tumors rather than geometry, or if longer follow-up revealed late chondritis that chart review missed. It leaves untouched the comparison with Mohs excision, which this cohort, already selected for RT in a multidisciplinary setting, cannot address.