1p19q codeletion

1p19q codeletion stands for the combined loss of the short arm chromosome 1 (“1p”) and the long arm of chromosome 19 (“19q”) and is recognised as genetic marker predictive of therapeutic response (both chemotherapy and combined chemoradiotherapy) and overall longer survival in patients with diffuse gliomas, especially those with oligodendroglial components 1-2, 4

The 1p19q codeletion is present in up to 70-85% of oligodendrogliomas and 50% of oligoastrocytomas 1,4.

A recent study showed that the presence of the 1p19q codeletion is a relevant marker of longer overall survival in patients with low grade gliomas and isocitrate dehydrogenase 1 (IDH1) mutation 3. In other words: 

  • IDH1 positive + 1p19q codeletion = better prognosis (oligodendroglioma / oligoastrocytoma)
  • IDH1 positive + no 1p19q codeletion = shorter overall survival (astrocytoma)

When the IDH1 is negative it corresponds to the ‘wild type’ and the tumour behave far more aggressively, and patients have a poor prognosis, similar to that of primary glioblastoma (GBM) 3

Astrocytic tumour
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Article Information

rID: 39164
Section: Pathology
Tag: cases
Synonyms or Alternate Spellings:
  • 1p-19q codeletion
  • 1p/19q codeletion
  • 1p/19q chromosome loss
  • 1p-19q chromosome loss

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