Phyllodes tumors of the breast: clinicopathological analysis of 106 cases from a single institution

Article type: Research Article

Authors: Efared, Boubacar^{a; *} | Ebang, Gabrielle Atsame^a | Tahiri, Layla^a | Sidibé, Ibrahim S.^a | Erregad, Fatimazahra^a | Hammas, Nawal^{a; b} | Melhouf, Moulay Abdelilah^{c; d} | Banani, Abdelaziz^{c; d} | Chbani, Laila^{a; b} | Fatemi, Hinde El^{a; b}

Affiliations: [a] Department of pathology, Hassan II university hospital, Fez, Morocco | [b] Laboratory of biological and translational research, Faculty of medicine and pharmacology, Sidi Mohamed Ben Abdellah university Fez, Morocco | [c] Department of obstetrics and gynecology, Hassan II university hospital, Fez, Morocco | [d] Faculty of medicine and pharmacology, Sidi Mohamed Ben Abdellah university, Fez, Morocco

Correspondence: [*] Corresponding author: Corresponding author: Boubacar Efared. E-mail: befared2013@gmail.com

Abstract: BACKGROUND:Phyllodes tumors (PT) are uncommon biphasic tumors, accounting for less than 1% of all breast primary neoplasms. They form a wide variety of tumors ranging from benign to malignant. Several histological features are used to grade PT into 3 categories: benign (grade I), borderline (grade II) and malignant (grade III) tumors. The aim of our study was to analyse histolopathological, radiological and clinical features of PT from an experience of a single center. METHODS:It was a retrospective study including 106 patients diagnosed with phyllodes tumors on surgical specimens at the department of pathology, of Hassan II university hospital (Fez, Morocco), from 2009 to 2016. RESULTS:The mean age was 33.81 years (range of 13–66 years), and the mean age increases with the tumor grade (mean ages of 32.32, 32.87 and 33.65 years respectively for grade I, II and III PT) (p = 0.023); 78 patients (73.58%) had benign PT, 20 (18.86%) had borderline PT and 8 (7.54%) patients were diagnosed with malignant PT. Mostly, the tumor size was <5 cm (63.2%), with BI-RADS 3 (51 patients, 48.11%). The tumor size and the radiological suspicion (ACR/BI-RADS) increased with the tumor grade (p < 0.001). Mitosis count, cellular atypia and stromal cellularity increased with the tumor grade (p < 0.001). Also, the presence of necrosis is associated with malignant PT (p < 0.001). Before surgery, patients had undergone core needle biopsies (CNB) for diagnostic purpose, and the overral sensitivity of this diagnostic procedure was 71.83%. The sentivity of the CNB decreased from grade I PT to grade III PT (from 56.81% to 37.5%), however its specificity increased from grade I to grade III PT (from 59.25% to 100%). CONCLUSION:Phyllodes tumors of the breast are rare neoplasms with a wide range of clinicopathologic presentations. The core needle biopsy has a good diagnostic sensitivity compared to definitive diagnosis on surgical specimens. There was a statistically significant association between the histological grade of PT and tumor size, radiological suspicion, mitotic count, cellular atypia, stromal cellularity, and tumor necrosis.

Keywords: Breast, phyllodes tumor, pathology

DOI: 10.3233/BD-170297

Journal: Breast Disease, vol. 37, no. 3, pp. 139-145, 2018