At a British sarcoma referral centre, three women with Turner syndrome have been diagnosed with gastrointestinal stromal tumours, the so-called GISTs. Add the single case published previously in the literature and the tally reaches four. The authors of the report, published in ESMO Gastrointestinal Oncology, are candid about what that means: an observation that opens a question, not proof that the syndrome predisposes to these tumours.
It helps to start with what a GIST is. These are tumours that grow in the wall of the digestive tract, most often in the stomach, and they arise from the interstitial cells of Cajal, a kind of pacemaker for intestinal movement. Behind that single label there are really three molecular families: those carrying a mutation in KIT, those carrying one in PDGFRA, and those with no mutation in either gene. That last group, the so-called wild-type tumours, is the one that appears clearly in neurofibromatosis type 1, an inherited syndrome in which the link is well established. With Turner syndrome there was nothing comparable: just one previously published case, far too little to speak of a relationship.
The team reviewed the records of the three patients seen at their centre retrospectively and examined the clinical, pathological and molecular data already produced in routine diagnosis, both from the tumour and from the germline. The first woman was 53 and had a gastric GIST with an uncommon mutation in exon 17 of KIT; she was treated with surgery and remained on surveillance alone. The second, aged 64, had two synchronous gastric GISTs that were molecularly distinct from each other, each with a different PDGFRA mutation. The third is the most puzzling: a 12-year-old girl with an SDH-deficient gastric GIST that had ruptured and who later developed disease in the liver and mediastinum, a picture consistent with the Carney triad spectrum.
That last case is the most informative. SDH-deficient GISTs have a biology of their own: they tend to be gastric, they turn up in young people, and they are precisely the ones seen in Carney triad, an uncommon constellation in which this type of gastrointestinal tumour coincides with pulmonary chondromas and paragangliomas. That the disease spread to the liver and mediastinum in a teenager is no side detail: it calls for a different follow-up and for thinking beyond the first tumour. The second case deserves attention for another reason: two independent tumours in the same stomach, with different mutations, suggest that if an underlying predisposition existed it might act more than once and through different molecular routes. And the first, with that rare KIT variant, rules out dismissing the whole matter as a quirk of the most familiar pathway.
The authors themselves hold back from any alarmist reading. Four cases are far too few to claim that women with Turner syndrome face a higher risk of GIST; the work comes from a single centre, is retrospective and has no comparison group, so there is no denominator: we do not know how many women with Turner syndrome have been studied in total, nor how many GISTs would be expected by chance alone. On top of that comes the classic publication bias: a surprising case gets written up and published far more readily than an unremarkable one. That is why the authors describe their finding as hypothesis-generating and call for clarity on whether the association is real, rather than proposing any screening. The paper contains no surveillance recommendation for all women with Turner syndrome, and reading it as one would be a mistake.
So what practical use does it have? For families, no cause for alarm: GIST is an uncommon tumour and these four cases change nobody’s individual risk. For clinicians, there are two sensible lessons. The first is not to put every persistent digestive symptom — pain, early fullness, anaemia or a palpable mass — down to the syndrome, and to investigate the patient as any other person would be investigated. The second is that molecular analysis of the tumour and germline sequencing matter, because they change management: an SDH-deficient GIST is not followed the same way as one with a KIT mutation, and its presence may prompt a search for other tumours in the Carney spectrum. A third task is more collective: report the cases. Only by accumulating well-described observations will it be possible to answer the question this paper leaves open — whether Turner syndrome and these tumours share anything beyond coincidence.
Source: GIST in Turner Syndrome. Williams SE, Fu AZ, Williams I, Giger O, Safranek P, Napolitano A, Jones RL, Bulusu R. ESMO Gastrointestinal Oncology 2026;14(100431). DOI: 10.1016/j.esmogo.2026.100431.
Read the paper: https://doi.org/10.1016/j.esmogo.2026.100431 · PubMed 42959697
