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Home > G. Tumoral pathology > Molecular pathology of tumors > Genetic anomalies > Cancer cytogenetics > Tumoral isochromosomes > i(17q)


Wednesday 22 September 2004


Definition: Isochromosome 17q, or i(17q), is one of the most common structural abnormalities observed in human neoplasms.


- hematologic malignancies

  • myeloproliferative/myelodysplastic diseases (MPD/MDS)
  • testicular granulocytic sarcoma (18262059)

- medulloblastoma (most frequent chromosomal rearrangement) (16419060)

As sole cytogenetic aberration

- i(17q) as sole cytogenetic aberration represents only 1% of cases in myeloid malignancies.


- Myeloid neoplasms with isolated isochromosome 17q represent a clinicopathologic entity associated with myelodysplastic/myeloproliferative features, a high risk of leukemic transformation, and wild-type TP53. Kanagal-Shamanna R, Bueso-Ramos CE, Barkoh B, Lu G, Wang S, Garcia-Manero G, Vadhan-Raj S, Hoehn D, Medeiros LJ, Yin CC. Cancer. 2012 Jun 1;118(11):2879-88. doi : 10.1002/cncr.26537 PMID: 22038701 [Free]

- Bettio D, Venci A, Sarina B. Near-tetraploid karyotype with an isochromosome 17q as the sole structural chromosomal rearrangement in a case of testicular granulocytic sarcoma. Cancer Genet Cytogenet. 2008 Feb;181(1):69-71. PMID: 18262059

- Mendrzyk F, Korshunov A, Toedt G, Schwarz F, Korn B, Joos S, Hochhaus A, Schoch C, Lichter P, Radlwimmer B. Isochromosome breakpoints on 17p in medulloblastoma are flanked by different classes of DNA sequence repeats. Genes Chromosomes Cancer. 2006 Apr;45(4):401-10. PMID: 16419060

- Isochromosome 17q is a negative prognostic factor in poor-risk childhood medulloblastoma patients. Pan E, Pellarin M, Holmes E, Smirnov I, Misra A, Eberhart CG, Burger PC, Biegel JA, Feuerstein BG. Clin Cancer Res. 2005 Jul 1;11(13):4733-40. PMID: 16000568 (Free)

- The effect of isochromosome 17q presence, proliferative and apoptotic indices, expression of c-erbB-2, bcl-2 and p53 proteins on the prognosis of medulloblastoma. Nam DH, Wang KC, Kim YM, Chi JG, Kim SK, Cho BK. J Korean Med Sci. 2000 Aug;15(4):452-6. PMID: 10983696 [Free]