Two doses of vitamin D and the chemotherapy did not have to stop

Design

retrospective multicentre case series across three academic centres

Population

33 patients with toxic erythema of chemotherapy (28) or acute radiation dermatitis (5)

Primary outcome

time to patient-reported symptom relief and clinician-rated erythema improvement

Effect

relief in 26 of 30 (87%) within 10 days; mean erythema score 4.36 to 2.21 by day 10; 73% continued anticancer therapy

Thirty-three patients across three academic centres received one or two oral doses of 100,000 international units of cholecalciferol or ergocalciferol for severe cutaneous toxicity of cancer treatment — 28 with toxic erythema of chemotherapy, five with acute radiation dermatitis — and were followed for at least ten days. This is a retrospective case series, assembled from what happened rather than designed.

Twenty-six of 30 assessable patients (87%) reported symptomatic relief within ten days. Median time to improvement was 5 days (range 1 to 28), and 3 days (1 to 16) among inpatients. Mean clinician-rated erythema on a five-point scale fell from 4.36 to 2.21 by day 10. The subtypes that responded fastest were neutrophilic eccrine hidradenitis and the Stevens-Johnson-like presentations. Serum calcium did not change meaningfully, no treatment-related adverse events were recorded, and 24 of 33 (73%) continued their anticancer therapy without interruption.

That last number is the one an oncologist will care about. Severe cutaneous toxicity usually buys a treatment break, and treatment breaks cost tumour control. An intervention that is two tablets, costs almost nothing and has a wide safety margin is worth considering in exactly the situation where the alternative is stopping chemotherapy.

The design limits what can be claimed. There was no comparator, these eruptions often settle on their own within one to two weeks, and a series of 33 assembled retrospectively will include the patients who did well. Nothing here establishes that vitamin D caused the improvement.

• Consider high-dose oral vitamin D when the alternative is interrupting anticancer treatment, and discuss it with the oncology team first
• Check a baseline calcium, but do not expect a change at one or two doses of 100,000 international units
• Keep the usual supportive measures — emollients, potent topical steroid, analgesia, cooling — this is an addition, not a replacement
• Photograph the eruption and grade the erythema, so response can be judged against something
• Exclude the diagnoses that need different treatment: cellulitis, drug reaction with eosinophilia and systemic symptoms, true Stevens-Johnson syndrome

Why it matters

The decision this touches is not dermatological — it is whether the oncologist has to pause treatment.

Don't overread it

A retrospective case series with no control group cannot show that vitamin D caused the improvement in conditions that often resolve on their own.

The statistics, in plain English

There is no control group, so none of these numbers is a treatment effect. A median 5 days to improvement sits inside the window in which toxic erythema of chemotherapy commonly settles anyway, and the erythema score fell on a five-point Likert scale rated by unblinded clinicians who knew what had been given. The 73% who continued anticancer therapy is the most useful figure precisely because it is a hard outcome, but without a comparator it cannot be compared with anything.

Read the rest in the app

You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.

Get Daily Doctor — free

Scan to keep reading on your phone. No account needed to start.