A Rare Case of Spindle Cell Sarcoma Presenting as a Recurrent Breast Cyst

Primary sarcomas of the breast are rare neoplasms which comprise between 0.2%-1.0% of all breast malignancies. They often carry a poor prognosis with mortality rates greater than 40%. In addition, these malignancies can be difficult to diagnose in a timely fashion as they can mimic other benign breast pathologies such as cysts. Here we present a case of a primary spindle cell carcinoma of the breast in a 53 year old female with fibrocystic breast disease which presented as a recurrent large breast cyst. Although she underwent a cyst aspiration and a FNA biopsy of her breast lesion during outpatient visits the results of both were negative for malignancy. Following suspicious mammography findings the patient underwent a breast cyst resection. A diagnosis of a high grade spindle cell sarcoma was made after immunohistochemical analysis showed a tumor in the wall of the cyst staining positive with Vimentin, Smooth Muscle Antigen (SMA) and Ki-67 as well as focal positive staining with S100, CD 68, p63. Despite undergoing a completion mastectomy and resection of the pectoralis major the patient’s sarcoma recurred one month later and she subsequently refused further treatment. We have illustrated a rare case of primary spindle cell sarcoma of the breast which presented as a recurrent breast cyst that had a negative cytology as well as a negative FNA. Clinicians should be aware of such atypical presentations as delays in diagnosis can contribute to the mortality rates of this rare but aggressive malignancy. Boris Hristov and Saptarshi Biswas* Department of Acute Care Surgery, Forbes Regional Hospital, Pennsylvania, USA Saptarshi Biswas, et al., Clinics in Oncology General Oncology Remedy Publications LLC., | http://clinicsinoncology.com/ 2017 | Volume 2 | Article 1292 2 in the left breast that was associated with pain, nipple retraction, erythematous changes, and purple discoloration along with peau d'orange skin which was hot to touch (Figure 4a and b). A lumpectomy and cyst excision was performed on September 16, 2013 in Brookdale Hospital and the initial frozen sections only showed spindle cells. Permanent sections were sent to Johns Hopkins for analysis. The Immuno-histochemistry study revealed positive staining with Vimentin, smooth muscle antigen (SMA), Ki-67, focal positive staining with S100, CD 68, p63. There was negative staining with Actin, Desmin, AE-1/AE-3, CAM5, GCDFP-15, ER, Mammaglobin, GATA-3, CK903, CK5, 6, HER2/NEU, Melan A and HMB46. These established histological features of a malignant spindle cell tumor as well as the immunohistochemical results led to the diagnosis of invasive malignant spindle cell neoplasm of high grade with scattered associated osteoclast like giant cells. Subsequently, staging Computed Tomography (CT) scans of the thorax, abdomen and brain were negative for metastases. The patient underwent completion mastectomy of the left breast and excision of pectoralis major muscle in November 2013 (Figure 5); axillary lymph nodes were not excised. Routine hematological and biochemical examinations, Ca15–3, and CEA were found to be normal. Her final pathology report is consistent with a high grade spindle and epithelioid neoplasm. The tumor was seen in multiple foci measuring from 0.5cm to 5cm in Figure 1: Left breast mammogram showing a large 12cm mass, that was not present on prior imaging. Figure 2: Ultrasound of left breast showing large 9.8cm x 6.9cm x 10cm cyst. Figure 3a: Closer ultrasound of left breast cyst wall showing irregular border. Figure 3b: Doppler ultrasound showing hyper vascular cyst wall. Figure 4a: Left breast prior to mastectomy. Figure 4b: Left breast prior to mastectomy. Figure 5: Left breast post mastectomy specimen. Saptarshi Biswas, et al., Clinics in Oncology General Oncology Remedy Publications LLC., | http://clinicsinoncology.com/ 2017 | Volume 2 | Article 1292 3 greatest dimension and the margins were clear.