INTRODUCTION:Primary chest wall tumors are uncommon, with 50-80 % of these tumors being malignant in nature. The most common primary malignant chest wall tumors are malignant fibrous histiocytoma, rhabdomyosarcoma and chondrosarcoma. Some of the more common primary benign chest wall tumors cartilaginous tumors, desmoids and fibrous dysplasia. We present an uncommon case of a fibromatosis with keloid features of the lung, which was initially thought to be a pleural effusion.
CASE PRESENTATION:44 year old female presents to her physician’s office for progressive worsening dyspnea over 2 months. The symptom worsened with exertion and was associated with occasional nonproductive cough. She never smoked and works as a health care professional. She received BCG vaccination as a child and immigrated to the United States 15 years ago. Though she reported to have several positive PPDs, her chest x-rays (CXR) were always normal. She was afebrile and other vitals were notable for a respiratory rate of 22 and oxygen saturation of 95%. Physical exam was remarkable for a trachea shifted to the left, absent breath sounds and dullness to percussion over the right chest. CXR demonstrated a large right sided effusion (Fig. 1.). Patient underwent thoracentesis, after being moved to the emergency room. 800ml of amber colored, exudative fluid was obtained after considerable difficulty. The pleural was described as being “thick” during the procedure. As the patient refused admission, a CT of the chest was performed as an outpatient. Our patient was referred for video-assisted thoracic surgery (VATS) with pleural drainage, biopsy and pleurodesis. During the VATS, a large mass was encountered requiring conversion to an open thoracotomy and subsequent removal of a 21cm × 18cm × 13cm mass with pleural peel weighing 2000 grams (Fig. 2) Histopathology initially described a benign spindle cell tumor such as neurilemmoma (schwannoma). Confirmatory immuno-histochemical staining favored fibromatosis with keloid features.
DISCUSSIONS:Classification of chest wall tumors can be divided into four categories, primary neoplasm of chest wall (either benign or malignant,) metastatic neoplasm to the chest wall (sarcoma, carcinoma,) adjacent neoplasm with local invasion such as lung, breast, pleural tumors, or non-neoplastic disease such as cysts or inflammation. Fibromatosis is a benign neoplasm derived from fibrous tissue that arises in musculoaponeurotic structures from the supporting connective tissue. The tumor occurs most frequently in the musculature of the anterior abdominal wall. Musculoaponeurotic fibromatosis, extra-abdominal desmoid aggressive fibromatosis, and low-grade sarcoma are the variety of terms used to describe this lesion. Heredity, hormones, trauma, and a previous surgical incision have been indicated as etiologic factors. Cytogenetic abnormalities consistent with clonality have also been reported. 2 Wide local excision with negative pathologic margins is the treatment of choice for most desmoid tumors. Function-sparing resection is appropriate because adjuvant radiation therapy can offset the adverse impact of positive margins. Unresectable disease should be treated with definitive radiation therapy. 3 Tumor regression has been reported in advanced inoperable fibromatosis with conventional chemotherapy, such as vincristine, dactinomycin, and cyclophosphamide, or more recently, with a weekly schedule of vinblastine and methotrexate. Hormonal therapy with tamoxifen could be an alternative treatment option in estrogen receptor–positive fibromatosis.
CONCLUSION:We present an unusual case of fibromatosis of the lung. Fibromatsosis (desmoid tumor) is an uncommon tumor, which can arise in the chest cavity and can first come to attention on routine imaging and be misdiagnosed as an effusion.
DISCLOSURE:Raju Thakor, No Financial Disclosure Information; No Product/Research Disclosure Information