Breast lesions with a significant spindle cell or mesenchymal component are not commonly encountered in fine-needle aspiration (FNA) cytologic material and include a heterologous variety of benign and malignant conditions, with phyllodes tumors (PTs) being the foremost differential diagnostic consideration. This study comprises 28 tumors diagnosed histologically as PT in which FNAC material was available for review. Histological sections and cytological smears from these cases were retrieved and subjected to detailed morphological review. Cytological parameters assessed included ratio of stroma to epithelium, pattern characteristics and cytological characteristics of the stromal, and epithelial components and the background cells. Large and hypercellular stroma fragments, dissociated spindle and plump stromal cells, often accompanied by large, folded sheets of epithelium were cytological features that characterized PT. Smears from malignant PT showed predominantly or solely mesenchymal components. FNAC was a highly reliable procedure for the diagnosis of PT, giving an accuracy rate of 92.8%.
Phyllodes tumor or cystosarcoma phyllodes is a rare fibroepithelial neoplasm which arises from the periductal stroma of the breast. They are classified as benign, borderline, and malignant based on the histologic features. However, all phyllodes tumor (PT) subtypes are regarded as having malignant potential and correct diagnosis is important for surgical management and optimal care. This study is a retrospective review of 76 women diagnosed as PT with highlights on the imaging characteristics, pathology, and surgical treatment over a 7-year period in a tertiary medical center of urban population in Malaysia. There were 45 benign, 16 borderline, and 15 malignant PT. The median age for benign PT was 43, borderline 48.5, and malignant 42 years. The Malay ethnic group constitute 52.6% of cases, with 27.6% and 18.4% in Chinese and Indian ethnic groups, respectively. On mammograms, most benign (64.3%) and 33.3% of malignant PT showed high-density lesions. Calcifications were only seen in 2 benign PT. On ultrasound, 86% of benign PT was well-circumscribed whilst 50.0% of malignant PT had irregular outline. Cystic spaces were seen in 40.0% of malignant and 9.5% of benign PT. 80% of malignant PT lesions were heterogenous. Malignant PT demonstrates tumor heterogeneity, cystic spaces, and posterior acoustic enhancement on ultrasound. Half of malignant PT showed regular borders on ultrasound and appear well circumscribed on mammogram. A total of 46 patients had wide local excision or excision biopsy whilst 30 underwent mastectomy as primary treatment. The majority of the borderline and malignant PTs in our study (75.0% and 85.7% respectively) and only 5 out of the 43 (11.6%) benign PT underwent mastectomy. There were 2 tumor recurrence in the benign PT group and 1 case in the borderline and malignant group respectively.
Taking cognizance of the purported variation of phyllodes tumours in Asians compared with Western populations, this study looked at phyllodes tumours of the breast diagnosed at the Department of Pathology, University of Malaya Medical Centre over an 8-year period with regards to patient profiles, tumour parameters, treatment offered and outcome. Sixty-four new cases of phyllodes tumour were diagnosed during the period, however only 30 (21 benign, 4 borderline and 5 malignant) finally qualified for entry into the study. These were followed-up for 4-102 months (average = 41.7 months). Thirteen cases (8 benign, 3 borderline, 2 malignant) were Chinese, 9 (all benign) Malay, 7 (4 benign, 1 borderline, 2 malignant) Indian and 1 (malignant) Indonesian. Prevalence of benign versus combined borderline and malignant phyllodes showed a marginally significant difference (p=0.049) between the Malays and Chinese. Patients' ages ranged from 21-70 years with a mean of 44.9 years with no significant difference in age between benign, borderline or malignant phyllodes tumours. Except for benign phyllodes tumours (mean size = 5.8 cm) being significantly smaller at presentation compared with borderline (mean size = 12.5 cm) and malignant (mean size = 15.8 cm) (p<0.05) tumours, history of previous pregnancy, breast feeding, hormonal contraception and tumour laterality did not differ between the three categories. Family history of breast cancer was noted in 2 cases of benign phyllodes. Local excision was performed in 17 benign, 2 borderline and 3 malignant tumours and mastectomy in 4 benign, 2 borderline and 2 malignant tumours. Surgical clearance was not properly recorded in 10 benign phyllodes tumours. Six benign and all 4 borderline and 5 malignant tumours had clearances of <10 mm. Two benign tumours recurred locally at 15 and 49 months after local excision, however information regarding surgical clearance was not available in both cases. One patient with a malignant tumour developed a radiologically-diagnosed lung nodule 26 months after mastectomy, was given a course of radiotherapy and remained well 8-months following identification of the lung nodule.