Phyllodes Tumor in a Lactating Breast

Phyllodes Tumor of the Breast Complicated With Mastitis

One of the rarest fibro-epithelial neoplasms of the breast during pregnancy is the phyllodes tumor (PT). It is typically a painless, bi-phasic, and rapidly growing neoplasm that resembles fibroadenomas. It is still unclear if the neoplasm is hormone-dependent during pregnancy. It is often challenging to diagnose and treat PT. Herein, we report a case of a 30-year-old female at 31 weeks gestation who was diagnosed with a benign phyllodes tumor of her breast with concurrent mastitis. She was first seen during her third trimester where the neoplasm was around 5 cm as reported by the ultrasound (US) examination. Her biopsy report was suggestive of a PT and she was advised surgery with excision of the tumor margin, but she refused. Ten days after her delivery she presented to the emergency department with a fever and a hard, engorged, erythematous, and tender left breast. She was diagnosed with mastitis of the left breast. She then underwent incision and drainage of the left breast that drained purulent milk; additionally, large necrotic grape-like tissues were removed and were confirmed by the histopathology report as a benign phyllodes tumor of the breast.

Genomic characteristics of two breast malignant phyllodes tumors during pregnancy and lactation identified through whole-exome sequencing

Background

The genomic landscape of breast malignant phyllodes tumors (PTs) is not well defined, especially pregnancy-related malignant PTs. To clarify this topic, whole-exome next-generation sequencing (NGS) was performed on tumor samples and paired normal breast tissues from two pregnancy-related malignant PTs, followed by a functional analysis of the genetic alterations.

Methods

DNA from malignant PT samples and matched normal breast tissues of both patients were subjected to molecular profiling. NGS of the whole-exome was performed in a commercial molecular pathology laboratory. Predictive tools were used to estimate genetic variation in somatic and germline genes.

Results

In total, 29 somatic genomic alterations and 18 germline alterations were found in both patients. In Patient 1, 12 aberrations were identified in the tumor tissue, and 9 alterations were identified in matched normal breast tissue. One pathogenic variant in tumor suppressor genes (TP53) was detected in patient 1. In Patient 2, 18 and 10 variants were found in the tumor and matched normal breast tissue, respectively. In Patient 2, pathogenic alterations were identified in two tumor suppressor genes (PTEN and TP53). PTEN and TP53 may be potential drug targets. The functional predictive tools showed that genes of unknown significance for PTs, including FCHO1 in Patient 1, and LRP12 and PKM in Patient 2, were pathogenic. Several genes, including FCHO1, LRP12 and PKM, were shown for the first time to be altered in malignant PTs. A potentially pathogenic germline variant in PRF1, was detected in Patient 1.

Conclusion

Our study first demonstrated somatic and germline gene alterations in two malignant PTs during pregnancy and lactation. These two PTs shared major genetic events, including TP53 mutation, which commonly occurs in malignant PTs; additionally, we identified two potential genes for targeted therapy, TP53 and PTEN. One germline mutation in PRF1 was also detected. These results provide clues regarding tumor pathogenesis and precision therapy development.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02537-w.

miR-140-3p is a potential differential biomarker in benign phyllodes tumors and fibroadenoma of the breast

Background

Benign phyllodes tumor (BPT) and fibroadenoma (FA) have some difficulties in differential diagnosis. BPT is often misdiagnosed as FA during the first operation and is not diagnosed until postoperative recurrence and reoperation. The intent of this research was to find and validate microRNAs (miRNAs) with significant differential expression between BPT and FA as novel potential differential biomarkers.

Methods

Tissue specimens from three BPT patients and three FA patients were selected to detect the expression of miRNAs by miRNA-Seq technique. Primary cells were extracted and cultured from fresh BPT and FA tissues by tissue-block culture. The expression of differentially expressed miRNA (DEmiRNA) was further verified by quantitative real-time polymerase chain reaction (qRT-PCR) in twelve BPT and eleven FA patient specimens as well as primary cells. Data with a P value < 0.05 were considered statistically significant.

Results

The miRNA-Seq results showed totally six DEmiRNA were identified, consisting of two downregulated genes and four upregulated genes in BPT. Further validation by qRT-PCR manifest that miR-140-3p was downregulated by approximately 70% in BPT.

Conclusion

miR-140-3p could become potential differential biomarker for BPT and FA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-022-01613-4.

Phyllodes Tumor of the Breast in Pregnancy and Lactation

Phyllodes tumor constitutes around 1% of all and 2.5% of fibroepithelial breast lumps. Three types including benign, borderline, and malignant tumors have been described. The benign variant is the most common, is close to fibroadenoma, but is usually larger and recurs more frequently. The rare malignant type is aggressive. Standard treatment consists of lumpectomy with appropriate margins for benign phyllodes tumor, while the borderline and malignant variants must be treated by wide resection or mastectomy. Phyllodes tumor is a rare tumor in pregnancy and lactation, and the effect of gestational alterations in hormone levels on this tumor have not been discussed in the literature, except for several case reports. In summary and alluding to our recent literature review, large size, fast growth, bilaterality, and probably malignancy are more commonly expected in gestational phyllodes tumors.

Massive Benign Phyllodes Tumour of Breast Complicating Pregnancy

Phyllodes tumour of the breast, earlier called cystosarcomaphyllodes, is a rare fibroepithelial breast neoplasm that occurs in all age groups from adolescents to elderly. Phyllodes tumour occurring during pregnancy and associated with lactating breast is extremely rare. Giant phyllodes tumours or giant fibroadenomas are those measuring more than 10 cms in diameter and weighing more than 500 gm. Phyllodes tumour typically exhibits an exclusive intracanalicular growth pattern of fibroepithelial cells with classical, deep leaf-like stromal projections into dilated lumens from which its name "phyllodes" is derived. A 32-year-old primigravida at 38 weeks of gestation, presented with massive and heavy swelling of the left breast, growing over the last eight months. Physical examination revealed a massively enlarged left breast with palpable, firm, nodular mass measuring 10 x 20 cm and occupying whole of the left breast. A trucut biopsy demonstrated a fibroepithelial lesion suggestive of benign phyllodes tumour. Simple mastectomy was performed six days after the delivery of the baby by caesarean section. The histopathological report confirmed the diagnosis as benign phyllodes tumour with ductal hyperplasia and no atypia. We are reporting this case because of its massive size, associated with lactating breast and difficulty in histopathological differentiation from Giant fibroadenoma.