Desmoid Tumor and Implant-Based Breast Reconstruction.

Desmoid tumors are rare locally aggressive myelodysplastic tumors that are usually abdominally based. They account for 0.2% of breast tumors. Certain factors like prior surgery, familial adenomatous polyposis, pregnancy, and high estrogen states are associated with chest wall desmoid tumor occurrence. We present a patient with a history of intraductal carcinoma of the left breast who underwent mastectomy with implant-based reconstruction who had a desmoid tumor of the breast detected during workup for cardiac transplantation for chemotherapy-induced heart failure. The tumor was originally thought to be recurrent breast cancer during workup with imaging obscured by the implant. Excisional biopsy demonstrated a desmoid tumor with a positive deep margin requiring rib resection, synthetic mesh, and pectoralis major flap reconstruction. Breast desmoid tumors are reactive malignancies that have been diagnosed after prior breast implant surgery but without an established risk associated with breast implants. Excision with microscopically negative margins and chest wall reconstruction when indicated is the current established treatment protocol; however, recent paradigm shifts include "watchful waiting" and medical management among treatment strategies.

Proteus empyema as a rare complication from an infected renal cyst, a case report.

BACKGROUND: The most commonly isolated organisms in a parapneumonic effusion include S. pneumoniae, H. influenzae, and S. aureus. If unusual organisms are isolated from the pleural space, further investigation is warranted to locate the primary source. We present a patient with an infected chronic renal cyst found to have an empyema secondary to Proteus mirabilis to highlight the importance of further diagnostic workup when encountering unusual organisms in the pleural space. CASE PRESENTATION: A 40-year-old African-American female, with a past medical history of asthma and sickle cell trait, presented with 5 weeks of upper respiratory tract symptoms and chest pain. A computed tomography angiogram (CTA) of the chest was negative for a pulmonary embolism but revealed a loculated left sided pleural effusion with associated left-lower lobe consolidation. She was started on empiric antibiotics, and a chest tube was inserted with drainage of frank pus. Fluid gram stain was positive for gram negative rods. Intrapleural fibrinolytics were administered for 72 h given the presence of loculations. With no improvement following fibrinolytics, she was taken to the operating room for large bore chest tube placement and left visceral pleura decortication. Pleural fluid cultures speciated to Proteus mirabilis, so further cross-sectional imaging of her abdomen/pelvis was pursued to evaluate for a primary source. A complex cystic lesion in the upper pole of the left kidney that communicated with the ipsilateral diaphragm was identified. Subsequent drainage and culture of the renal cyst was positive for Proteus mirabilis. Given clinical improvement following these interventions she was discharged with an extended course of antibiotics with plans for repeat imaging following completion of treatment. CONCLUSIONS: While cases of Proteus mirabilis empyema have previously been reported as a consequence of conditions such as pyelonephritis, we present, to our knowledge, the first case of a Proteus mirabilis empyema as a consequence of an infected renal cyst communicating with the pleural space. This study highlights that further evaluation with cross-sectional imaging is warranted when unusual organisms are found in the pleural space. Anatomic abnormalities that become apparent on imaging may help elucidate the source of infection.

Clear Cell Sarcoma With Cutaneous Presentation in a 4-Year-Old Boy.

We report a case of a 4-year-old Brazilian boy, who presented with an erythematous and painful nodule involving the skin of his left arm. Immunohistochemistry was performed for S100, SOX10, CD34, desmin, SMA, HMB-45, CD1a, and CD163, and fluorescence in situ hybridization for EWSR1 gene rearrangement using a break-apart probe was completed. Immunohistochemistry showed bland spindle cells with "floret-like" appearance simulating a giant cell fibroblastoma; tumor cells were positive for S100 and SOX10; neoplastic cells were negative for CD34, desmin, SMA, HMB-45, CD1a, and CD163; and fluorescence in situ hybridization showed an EWSR1 gene rearrangement. We report the youngest known case of cutaneous involvement of clear cell carcinoma at the age of 4.

Educational Case: Pheochromocytoma.

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.