Technetium-99m-sestamibi scintimammography of benign and malignant phyllodes tumors

Phyllodes tumor of breast: a review article

Introduction. Phyllodes tumours are rare fibroepithelial lesions. Accurate preoperative pathological diagnosis allows correct surgical planning and avoidance of reoperation. Treatment can be either wide local excision or mastectomy to achieve histologically clear margins. Discussion. The exact aetiology of phyllodes tumour and its relationship with fibroadenoma are unclear. Women aged between 35 and 55 years are commonly involved. The median tumour size is 4 cm but can grow even larger having dilated veins and a blue discoloration over skin. Palpable axillary lymphadenopathy can be identified in up to 10-15% of patients but <1% had pathological positive nodes. Mammography and ultrasonography are main imaging modalities. Cytologically the presence of both epithelial and stromal elements supports the diagnosis. The value of FNAC in diagnosis of phyllodes tumour remains controversial, but core needle biopsy has high sensitivity and negative predictive value. Surgical management is the mainstay and local recurrence in phyllodes tumours has been associated with inadequate local excision. The role of adjuvant radiotherapy and chemotherapy remains uncertain and use of hormonal therapy has not been fully investigated. Conclusion. The preoperative diagnosis and proper management are crucial in phyllodes tumours because of their tendency to recur and malignant potential in some of these tumours.

Optimising preoperative diagnosis in phyllodes tumour of the breast

The role of the pathologist in the preoperative diagnosis of phyllodes tumours of the breast is critical to appropriate surgical planning. However, reliable differentiation of phyllodes tumour from cellular fibroadenoma remains difficult. Preoperative diagnostic accuracy allows correct surgical treatment, avoiding the pitfalls of reoperation because of inadequate excision, or surgical overtreatment. Specific clinical indices may arouse diagnostic suspicion but are unreliable for confirmation, as with current imaging modes. Fine needle aspiration cytology has a high false negative rate. Few studies have evaluated the role of core needle biopsy, but it may prove a useful adjunct. Both diagnostic and prognostic information may in future be gained from application of immunohistochemical and other techniques assessing the expression of proliferative markers including p53, Ki-67, and others.

Scintimammographic Findings of Phyllodes Tumor of the Breast in a Double-phase Study with Tc-99m (V)DMSA and Tc-99m MIBI: a Case Report

We present a case of phyllodes tumor of the breast in a 78-year-old woman evaluated with Tc-99m (V)DMSA and Tc-99m MIBI scintimammography, acquired in separate sessions (10 and 60 min post-injection). Tc-99m (V)DMSA was accumulated intensely within the mass [tumor to background ratio (T/B) >3], whereas Tc-99m MIBI had significantly lower uptake (T/B 1.9). Histology revealed a phyllodes tumor (maximum diameter 15 cm) and approximately three mitoses over 10 fields of view (FOV) x40, foci of epithelial hyperplasia and apocrine metaplasia. Stromal Ki-67 expression was 7%. The tumor was considered to be benign and the patient underwent mastectomy. One year later the patient presented with local malignant recurrence of the disease with over 15 mitoses per 10 FOV. Tc-99m (V)DMSA seems to have an advantage over Tc-99m MIBI in detecting mesenchymal tumors with unforeseen biological behavior and Ki-67 over-expression, such as phyllodes tumors, even with primary negative histological findings.

Phyllodes tumors of the breast

Phyllodes tumor is a rare fibroepithelial neoplasm of the breast with a very variable, but usually benign, course. Formerly known as cystosarcoma phyllodes, the designation "phyllodes tumor" with appropriate qualification regarding malignant potential based on pathologic features is now the agreed-upon term. The most important diagnostic distinction is from fibroadenoma--phyllodes tumors require complete excision with free margins even when pathologic features suggest benignity because of a proclivity to local recurrence. The most important component of therapy is wide surgical excision, and mastectomy is necessary only when free margins cannot be achieved without it. Involvement of axillary nodes is rare, and axillary dissection is not indicated. The role of radiation therapy and chemotherapy is not established and has not been studied in randomized trials due to the rarity of the tumor. At present, there is no consensus that patients with high-grade phyllodes tumors of the breast will benefit from either of these modalities.