Granular Cell Tumor of Breast: a Case Report and Review of Literature

Unusual cerebrospinal fluid finding of intracytoplasmic granules in metaplastic carcinoma of the breast with acinar differentiation

Cerebrospinal fluid (CSF) evaluation for total and differential cell count is a common practice in pathology for evaluation of various disease conditions. Although rare, these CSF samples yield interesting and unusual morphological findings, which are not only of academic interest, but also may play key roles in diagnosis. For diagnosing metastatic carcinoma in brain and meninges, CSF examination is one of the important tools along with imaging studies. Metaplastic breast carcinoma (MBC) encompasses a rare (<1% of all breast cancers), aggressive and highly heterogeneous group of tumors. MBC is almost always estrogen receptor, progesterone receptor and Her2 negative (triple negative) and shows frequent early distant metastases as well as sub-optimal response to systemic therapies. The involvement of leptomeninges is most commonly associated with these triple- negative subtypes. In this report, we present an unusual case of malignant cells with prominent intracytoplasmic granules in CSF smears of a 46-year-old female with metastatic MBC with acinar differentiation. An extensive review of literature in English language did not return any other reports of a similar finding.

Granular cell tumor of the breast: correlations between imaging and pathology findings

Objective

To review the imaging features of granular cell tumors of the breast (on mammography, ultrasound, and magnetic resonance imaging), establishing a pathological correlation, in order to familiarize radiologists with this entity and make them aware of the differential diagnoses, other than malignancy, of lesions with spiculated margins.

Materials and Methods

We reviewed the medical records (from a clinical-pathology database and picture archiving and communication system) of five patients with a pathologically confirmed diagnosis of granular cell tumor of the breast, treated at the Portuguese Oncology Institute of Lisbon, in the city of Lisbon, Portugal, between January 2012 and December 2018.

Results

All five tumors exhibited imaging features highly suggestive of malignancy (BI-RADS 5 lesions), namely spiculated margins, significant depth, and posterior acoustic shadowing (on ultrasound). One tumor showed a kinetic curve indicative of washout on magnetic resonance imaging, two were adherent to the pectoralis muscle, and one was accompanied by skin retraction. Pathology provided the definitive diagnosis in all cases.

Conclusion

Granular cell tumors of the breast pose a diagnostic challenge because they can present with clinical and imaging features mimicking malignancy, and the diagnosis is therefore provided by pathology. Radiologists should be familiarized with this entity, so they can be aware of the fact that breast lesions with spiculated margins can be indicative of diagnoses other than malignancy.

Pediatric Granular Cell Tumor of the Breast: An uncommon neoplasm in an uncommon site and age group

Granular cell tumor (GCT) is a rare soft tissue neoplasm of Schwann cell origin. Most cases occur in adults; however, the precise incidence is unknown in children. GCT is usually a slow-growing, painless tumor involving the skin and soft tissues that is mostly located in the head and neck region, especially the tongue. The breast is one of the least common sites involved by GCT. This paper presents a 3-year-old girl who presented with a soft to firm, ill-defined swelling on the right breast with painful ulceration of the overlying skin. Fine needle aspiration rendered an initial diagnosis of fibrocystic change accompanied by apocrine metaplasia. Histologic evaluation of the excised breast mass revealed a benign granular cell tumor. Although rare, GCT of the breast should be included in the differential diagnosis for breast masses in pediatric patients. Proper diagnosis and timely management of this tumor are essential because of its malignant potential (<2% of cases) and high rate of local recurrence if not properly excised.