Calcified Mediastinal Metastasis of Ovarian Cancer Mimicking Broncholithiasis

Broncholithiasis is disruption or distortion of bronchial wall/lumen by peribronchial calcified tissue (broncholith) with presence of calcified material in the airway.1 Common causes of broncholithiasis include erosion of calcified lymph nodes from prior fungal (frequently histoplasmosis) or mycobacterial infections. Uncommon causes include silicosis, aspiration of bone tissue, in situ calcification of aspirated foreign body, migration of calcified tissue from distal sites or erosion, and extrusion of calcified cartilage plates into airway.2,3 Conditions that mimic broncholithiasis include calcified endobronchial infections related to actinomycosis or calcified endobronchial tumors like carcinoids, hamartomas, chondrosarcomas, etc.2 In this report, we describe a case of tracheal invasion by heavily calcified metastatic right paratracheal lymph node, which mimicked the clinical presentation of broncholithiasis. CASE REPORT A 61-year-old woman with stage III C serous papillary adenocarcinoma of the ovary was treated with surgery followed by adjuvant chemotherapy. Twelve years later, the patient developed isolated metastatic disease to right supraclavicular lymph nodes; this was treated with 5 cycles of chemotherapy with complete radiologic response. Computerized tomography of the chest at this time showed calcified right paratracheal lymph nodes, presumed to be due to old granulomatous disease (Fig. 1A). A year later, the patient presented with intractable hemoptysis, potentially from the right paratracheal lymph node mass eroding into the trachea (Figs. 1B, C). Bronchoscopy revealed a firm mass adherent to the trachea with obstruction of the right mainstem bronchus (Fig. A). Given the slow growth of the mass, extensive calcification, lack of response to chemotherapy, and the bronchoscopic findings, a putative diagnosis of broncholithiasis was made. As torrential bleeding from bronchoscopic removal of broncholiths has been reported, surgical excision of the lesion was planned to control the hemoptysis. A right thoracotomy was performed and the lesion biopsied. Frozen section examination revealed probable metastatic ovarian cancer; this was confirmed on definitive pathologic examination (Fig. 2). Therefore, surgical resection was abandoned and radiation therapy was planned. Given the fact that the mass invaded the trachea and radiation therapy to treat it may lead to a tracheo-pleural fistula, the entire side of the trachea was covered with a serratus anterior flap. This was combined with bronchoscopic laser debulking to open up the right mainstem bronchus and to control the hemoptysis. The patient received adjuvant radiation to treat the paratracheal lesion, which responded to treatment. At last follow-up 3 years after the procedure, the patient remains alive and without progression of disease (Fig. 1D).FIGURE A: Bronchoscopy image showing tracheal mass with occlusion of the right mainstem bronchus.FIGURE 1: Computerized tomography (CT) scan of the chest axial view (A) shows calcified right paratracheal lymph nodes 1 year before presenting with hemoptysis. CT chest axial views (B, C) show erosion of calcified paratracheal mass into the trachea. CT chest axial view 3 years later (D) shows patent central airways and also the serratus anterior flap.FIGURE 2: Biopsy of right paratracheal mass showing adenocarcinoma (white arrow) with numerous psammoma bodies (black arrow) (hematoxylin and eosin staining, ×200 original magnification).DISCUSSION The diagnosis of broncholithiasis is usually made in the appropriate clinical setting with a radiologic picture suggesting calcified lymph nodes or lesions adjacent to the airway. The usual symptoms of broncholithiasis include cough, hemoptysis, postobstructive infections or lithoptysis (coughing up of calcified material). Diagnostic challenges include difficulty in the determination of endoluminal extent due to volume averaging artifacts on regular computerized tomographic imaging and, in certain cases, the inability to visualize the broncholith by bronchoscopy due to either overlying inflamed bronchial tissue or inaccessibility by regular bronchoscopy secondary to distal location. Broncholiths can be classified as intraluminal, extraluminal, and mixed depending on their relationship with the airway.4 Intraluminal broncholiths can be removed by bronchoscopy (with caution) while surgical removal is recommended for symptomatic extraluminal or mixed broncholiths.4,5 No intervention is recommended for asymptomatic extraluminal broncholiths. This case was unusual, as calcified metastatic tumor is usually not considered in the differential diagnosis of broncholithiasis. At the time of initial evaluation of supraclavicular recurrence, the right paratracheal calcified nodes were presumed to be due to old granulomatous infection. Metastatic site calcification inside pulmonary parenchyma or mediastinal lymph nodes is infrequent but has been rarely reported in several cancers including ovarian, breast, thyroid, colon, head and neck (squamous cell) cancer, and sarcoma.6–8 Metastasis of ovarian carcinoma to intrathoracic lymph nodes is uncommon with 1 large series reporting a low rate of only 2.3% (6 of 255 cases). Patel et al9 reported 5 women who developed isolated supra diaphragmatic metastasis from papillary serous ovarian cancer many years after remission of abdominal and pelvic disease, and in most cases, the metastatic sites demonstrated heavy calcification. One case mimicked metastatic thyroid carcinoma and another one simulated malignant mesothelioma due to calcified pleural metastasis. Overall calcification of ovarian cancer can be seen in approximately 8% cases with microscopic involvement of peritoneal surface being the most common site.10 Papillary serous ovarian cancers form psammoma bodies (microscopic concentric lamellated collection of calcium), which typically result in a punctate calcification pattern, however, these areas act as nidus for subsequent additional calcification thus resulting in amorphous pattern of calcification.10 To the best of our knowledge, a clinical presentation of metastatic heavily calcified mediastinal lymph node erosion into the airways and thereby simulating broncholithiasis has not been reported before. The clinical picture of metastatic calcification is a great mimicker as it can resemble not only broncholithiasis but also metastatic thyroid cancer or mesothelioma.9 Although the exact management is unclear, and will vary with clinical situations, our management of serratus anterior flap, limited laser photoresection, and mechanical debulking followed by external beam radiation worked well for this patient. In summary, calcification inside metastatic deposits of malignancies can present as a diagnostic dilemma and should be kept in the differential diagnosis of calcified lymph node and broncholithiasis, especially in patients with a history of prior malignancy.