PALB2 Variants Extend the Mutational Profile of Hungarian Patients with Breast and Ovarian Cancer

Henriett Butz; Petra Nagy; János Papp; Anikó Bozsik; Vince Kornél Grolmusz; Tímea Pócza; Edit Oláh; Attila Patócs

doi:10.3390/cancers15174350

PALB2 Variants Extend the Mutational Profile of Hungarian Patients with Breast and Ovarian Cancer

Cancers (Basel). 2023 Aug 31;15(17):4350. doi: 10.3390/cancers15174350.

Authors

Henriett Butz^{1

2

3

4}, Petra Nagy¹, János Papp^{1

3}, Anikó Bozsik^{1

3}, Vince Kornél Grolmusz^{1

3}, Tímea Pócza¹, Edit Oláh¹, Attila Patócs^{1

3

4}

Affiliations

¹ Department of Molecular Genetics, The National Tumor Biology Laboratory, National Institute of Oncology, Comprehensive Cancer Center, 1122 Budapest, Hungary.
² Department of Oncology Biobank, National Institute of Oncology, 1122 Budapest, Hungary.
³ Hereditary Tumours Research Group, Eötvös Loránd Research Network, 1089 Budapest, Hungary.
⁴ Department of Laboratory Medicine, Semmelweis University, 1092 Budapest, Hungary.

Abstract

Background: The pathogenic/likely pathogenic (P/LP) variant detection rate and profile of PALB2, the third most important breast cancer gene, may vary between different populations.

Methods: PALB2 was analyzed in peripheral blood samples of three independent cohorts: prospectively between September 2021 and March 2023 (i) in 1280 consecutive patients with breast and/or ovarian cancer (HBOC), (ii) in 568 patients with other cancers (controls), and retrospectively, (iii) in 191 young breast cancer (<33 years, yBC) patients. These data were compared with data of 134,187 non-cancer individuals retrieved from the Genome Aggregation Database.

Results: Altogether, 235 cases (235/1280; 18.3%) carried at least one P/LP variant in one of the HBOC susceptibility genes. P/LP PALB2 variants were identified in 18 patients (1.4%; 18/1280) in the HBOC and 3 cases (1.5%; 3/191) in the yBC group. In the control group, only one patient had a disease-causing PALB2 variant (0.17%; 1/568) as a secondary finding not related to the disease, which was similar (0.15%; 205/134,187) in the non-cancer control group. The NM_024675.4:c.509_510delGA variant was the most common among our patients (33%; 6/18). We did not find a significant difference in the incidence of PALB2 disease-causing variants according to age; however, the median age of tumor onset was lower in PALB2 P/LP carriers versus wild-type patients (44 vs. 48 years). In our cohort, the odds ratio for breast cancer risk in women with PALB2 P/LP variants was between 8.1 and 9.3 compared to non-HBOC cancer patients and the non-cancer population, respectively.

Conclusions: PALB2 P/LP variants are not uncommon among breast and/or ovarian cancer patients. Their incidence was the same in the two breast cancer cohorts studied but may occur rarely in patients with non-breast/ovarian cancer. The c.509_510delGA variant is particularly common in the studied Hungarian patient population.

Keywords: PALB2; breast cancer; genetic predisposition; genetic testing; genetics; hereditary; next-generation sequencing; ovarian cancer.

Abstract

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