Paget’s disease is a rare disease which classified as mammary (MPD) and extra-mammary (EMPD) types. Previous study reported the association between both groups of Paget’s disease and malignancies. However, little data in Thailand was known. So, our study was aimed to determine the incidence, associated malignancies and clinical outcomes of both groups of Paget’s disease in Thailand.
One hundred and fifty seven patients with histologically confirmed diagnosis of MPD or EMPD in King Chulalongkorn Memorial Hospital between 2007 and 2017 were retrospectively reviewed. Demographic data, secondary malignancies, histological characteristics and clinical outcomes were analyzed.
109 out of 157 (69.4%) patients had MPD, while 30.6% had EMPD. In MPD group, all were female, median age was 55 years (range 34-92), 82.6% had invasive breast cancer, 15.6% had ductal carcinoma in situ and only 3 patients (2.7%) had no underlying carcinoma. Among 90 patients with invasive breast cancer, 40% was ER positive and 61.1% was HER2 positive. In EMPD group, most are female (35/48 patients, 73%) and median age was 67 years (range 36-88), 53.2% presented with vulva as a primary lesion, and only 33% had identified secondary cancer. The most common cancer was urogenital tract cancer (25%), followed by breast cancer (18.8%) and cervical cancer (12.5%). 62.5% of associated cancers was recognized concurrently with diagnosis of EMPD, 6 patients (37.5%) were diagnosed before or after diagnosis of EMPD with the median of 1.1 year (range -7 to 6 years). For EMPD treatment, 83.3% underwent surgical resection, 52.5% had positive margin and 15% received post-operative radiation. In MPD, no recurrent on Paget’s lesion was found, while 37.5% of EMPD had recurred both locoregional and metastasis (24.5% and 6.1% respectively). Overall survival and recurrent free survival will be further analyzed.
Strong association of Paget’s disease and malignancy was identified in Thai patients. Higher recurrent rate in EMPD might lead the concern of adequate surgical management in order to improve long term outcomes.
Clinical trial identification
Legal entity responsible for the study
Medical oncology unit, King Chulalongkorn Memorial Hospital
All authors have declared no conflicts of interest.