Combined Use of Mammography and FNA Eliminates Pitfalls in the Management of Metaplastic Breast Carcinoma

BACKGROUND: Due to its heterogeneity, metaplastic breast carcinoma (MBC) poses diagnostic dilemmas, leading to delayed treatment, thereby aggravating the prognosis. Over the years, there has been controversy regarding the role of fine-needle aspiration (FNA) cytology in timely diagnosis. CASE REPORT: A 54-year-old woman presented with a palpable mass in the upper outer quadrant of her right breast with corresponding mammographic findings and FNA was performed. The smears revealed small- and medium-sized cohesive clusters of malignant cells with atypical nuclei. Sporadically, there was a pleomorphic population of notably large mononuclear cells, with disturbance of nuclear/cytoplasmic ratio, and binucleated or multinucleated malignant cells. The presence of chondromyxoid substance with focally embedded cells in a magenta-colored substrate was predominant in the background. These features, along with the corresponding mammographic findings, allowed for high preoperative suspicion of MBC. Surgical resection followed immediately without neoadjuvant chemotherapy; the pathology report led to the definite diagnosis of MBC. DISCUSSION: MBC is a rare clinical entity with unfavorable prognosis, thus early diagnosis is imperative regarding its management. The effectiveness of FNA in the diagnostic algorithm has been questioned, with data from literature being rather contradictory. FNA seems to provide valuable information, which should always be interpreted in correlation with the clinical and mammographic findings. CONCLUSION: High preoperative suspicion of MBC with the combination of mammography and FNA cytology necessitated the surgical excision of the lesion as the principal treatment approach. Although the role of FNA in the diagnosis of MBC is debatable, its combination with clinical presentation and corresponding mammographic findings may prevent the administration of neoadjuvant chemotherapy in patients with ambiguous indications, given the poor response rate of this cancer subtype.