Erciyes Tıp Genetik Günleri, Kayseri, Turkey, 21 - 23 February 2019, pp.16
Peutz-Jeghers Syndrome (PJS) is an inherited autosomal dominant disorder consisting of characteristic gastrointestinal (GI)
hamartomas, mucocutaneous pigmentations and predisposition to GI, breast and other cancers. In this study, we aimed to
present a common mutation in STK11 gene in PJS case with
early onset breast cancer. Our case is a 34-year-old woman.
She was referred us because of the early onset recurrent breast
cancer by oncology clinic. Pathology results were invasive ductal carcinoma and in situ multifocal solid papillary carcinoma
on left breast. After adjuvant chemotherapy, hamartomatous
polyp was detected in her colonoscopy following rectal bleeding. She had a history of left oophorectomy for benign reasons.
We detected pigmentations on lower lip mucosa, a brown
papule on nose and a brown macula at left palmar region. In
her family history, it was learned that her mother was operated
nasal polyp excision three times and aunt’s daughter had a
45-year-old breast cancer diagnosis and her 28-year-old sisters
had black spots on lips developed in childhood. Similar skin
lesions were present when the patient was a child. Next generation sequencing analysis for Hereditary Cancer Risk Panel
was studied for PJS genetic diagnosis. It detected nonsense,
heterozygous, c.250A>T pathogenic variation (rs137853076) on
the exon 1 of STK11 gene (ENST00000326873). In conclusion,
physical examination is indispensable for the diagnosis of
hereditary cancer syndromes. Molecular diagnosis of hereditary cancer syndromes give patient’s relatives the opportunity
to early diagnose and also risk reducing measures can prevent
cancer formation.