RESUMEN
Proliferative verrucous leukoplakia (PVL) is an oral mucosa lesion with a high rate of malignant transformation. The diagnosis is often difficult, especially when the initial lesion is a simple homogeneous white leukoplakia, and when located only on the gingiva or palate. Moreover, the anatomopathological analysis is non-specific in the initial stages. The gingival PVL localisation (gPVL) is described as the most aggressive form with the highest rate of malignant transformation. Cases with a unique gingival localisation are rare, described with a "ring around the collar" clinical form. Considering the difficulty of early diagnosis of gPVL, we report the case of a 72-year-old woman, who presented "white lesions on her gingiva" with a slight discomfort in February 2019. The lesion was initially limited to the buccal part of the mandibular right gingiva, but rapidly extended to all the lingual and buccal mandibular gingiva during follow-up, leading to a diagnosis of gPVL. Two biopsies were performed, which concluded a verrucous hyperplasia and papilloma with a lichenoid part. The diagnosis of gPVL was made after a six-month follow-up based on clinical and anatomopathological factors. The gPVL transformed into a squamous cell carcinoma (SCC) after 18 months of follow-up. A surgical right mandibular bone excision with an autologous left fibula graft associated with radiotherapy was performed. Three years after the surgery, the patient remains under monitoring, with several gPVL and SCC recurrences treated. This case highlights that gPVL is a rare and aggressive form of PVL, with a high risk of fast malignant transformation. Knowledge about its aetiology, anatomic pathology, and biological markers is highly needed to speed up the diagnosis and develop specific follow-up and treatment.
RESUMEN
BACKGROUND: The PALB2 gene encodes a protein that plays a crucial role in maintaining genomic integrity. Germline inactivating mutations in PALB2 are associated with an increased risk of breast and ovarian cancer. The prevalence and spectrum of recurrent PALB2 germline mutations in breast and ovarian cancer patients from Poland is not clearly defined. METHODS: PALB2 exons were amplified from 460 BRCA1/2-mutation negative women with familial breast and/or ovarian cancer and early-onset breast cancer using AmpliSeq technology and sequenced on an Ion Torrent PGM sequencer. In addition, eight selected variants were genotyped using TaqMan assays in 807 BRCA1/2-mutation negative breast cancer patients and 1690 healthy women. RESULTS: Two recurrent PALB2 mutations, c.172_175delTTGT and c.509_510delGA, were identified, along with one novel mutation, c.347insT. In total, PALB2 pathogenic mutations were detected in 7/460 (1.5%) patients. Furthermore, in breast and/or ovarian cancer patients, several single nucleotide variants (SNVs) were detected in the PALB2 coding region. In an additional group of 807 patients, eight (1%) carriers of two pathogenic mutations, c.172_175delTTGT (0.5%) and c.509_510delGA (0.5%), were identified. The c.509_510delGA mutation was not identified in healthy controls, while c.172_175delTTGT was identified in 4/1690 (0.24%) of control women. CONCLUSIONS: Germline mutations in the PALB2 gene were observed at a frequency of approximately 1.5% in Polish breast and/or ovarian cancer patients. Our study confirms two recurrent PALB2 mutations; c.172_175delGA and c.509_510delGA.
