CYSTIC ADENOMATOID MALFORMATION OF THE LUNG IN AN ADULT: A CASE REPORT

Abstract

SESSION TITLE: Remarkable Imaging CasesSESSION TYPE: Rapid Fire Case ReportsPRESENTED ON: 10/18/2022 12:25 pm - 01:25 pmINTRODUCTION: Congenital cystic adenomatoid malformation (CCAM) is a congenital abnormality of non-cartilaginous terminal respiratory structures. The disease occurs in neonates and is rarely seen after childhood. There are only a few cases of cystic adenomatoid malformation (CAM) that have been reported in adults [1]. We report a case of CAM in an adult with pleuritic chest pain who was found to have a mass on CT chest.CASE PRESENTATION: A 46 year old Chinese female presented to the emergency department (ED) with left-sided pleuritic chest pain. She has a history of tuberculosis (TB) that was treated in 1998. Prior to hospitalization, she was undergoing an outpatient pulmonary work-up for an abnormal CT chest which showed mediastinal lymphadenopathy and complete collapse of the left lower lobe (LLL) without visualization of the LLL bronchus. She had been scheduled for an outpatient bronchoscopy, but was sent to the ED for worsening pleuritic pain before it could be performed. In the ED, she denied any fevers, shortness of breath, or productive cough. An inpatient bronchoscopy and endobronchial ultrasound was performed; however, no endobronchial lesions, mucus plugs, or abnormal lymph nodes were seen. Bronchoalveolar lavage with cell count, acid-fast bacillus, cultures, and cytology was unrevealing. The team later discovered that she had a chest x-ray in China from 2015 that reported a LLL consolidation. Given the chronicity, there was concern for pulmonary sequestration. A CT chest with IV contrast was performed, which showed a 7 x 4 x 4.6 mass-like consolidation in the LLL (Figure 1,2) with no separate arterial supply, which made pulmonary sequestration unlikely. However, the mass had multiple areas of cystic changes, characteristic of cystic adenomatoid malformation of the lung. She was referred to a cardiothoracic surgeon for resection.DISCUSSION: CCAMs are bronchopulmonary malformations that are usually unilateral without lobar preference. The etiology is unclear, but is usually seen in neonates. These malformations can be described as cystic, intermediate, or solid [2]. The most common presentation in adults is recurrent pulmonary infections [1]. Other presentations include pneumothoraces, hemoptysis, or dyspnea. CAM can also be found incidentally on imaging; therefore, highlighting the usefulness of reviewing old imaging if available [1]. CT angiography is the best technique for diagnosis because it can help differentiate CAM from other conditions, such as pulmonary sequestration. Surgical resection is the main treatment option in order to prevent recurrent infections. Additionally, CCAMs can become cancerous; therefore, resecting them reduces the chance of malignant transformation [3].CONCLUSIONS: Although CAM is rarely seen in adults, it is important to keep it in the differential diagnosis for patients that present with recurrent pulmonary infections and unilateral cystic lesions of the lung.Reference #1: Herrero, Y., Pinilla, I., Torres, I., Nistal, M., Pardo, M., & Gómez, N. (2005). Cystic adenomatoid malformation of the lung presenting in adulthood. The Annals of thoracic surgery, 79(1), 326-329.Reference #2: Van Dijk, C., & Wagenvoort, C. A. (1973). The various types of congenital adenomatoid malformation of the lung. The Journal of Pathology, 110(2), 131-134.Reference #3: Granata, C., Gambini, C., Balducci, T., Toma, P., Michelazzi, A., Conte, M., & Jasonni, V. (1998). Bronchioloalveolar carcinoma arising in congenital cystic adenomatoid malformation in a child: a case report and review on malignancies originating in congenital cystic adenomatoid malformation. Pediatric pulmonology, 25(1), 62-66.DISCLOSURES: No relevant relationships by Sathya Alekhya Bukkurino disclosure on file for Jerry Ipe;No relevant relationships by Henry Mayo-MalaskyNo relevant relationships by Mangalore Amith ShenoyNo relevant relationships by Alexandra Zavin SESSION TITLE: Remarkable Imaging Cases SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/18/2022 12:25 pm - 01:25 pm INTRODUCTION: Congenital cystic adenomatoid malformation (CCAM) is a congenital abnormality of non-cartilaginous terminal respiratory structures. The disease occurs in neonates and is rarely seen after childhood. There are only a few cases of cystic adenomatoid malformation (CAM) that have been reported in adults [1]. We report a case of CAM in an adult with pleuritic chest pain who was found to have a mass on CT chest. CASE PRESENTATION: A 46 year old Chinese female presented to the emergency department (ED) with left-sided pleuritic chest pain. She has a history of tuberculosis (TB) that was treated in 1998. Prior to hospitalization, she was undergoing an outpatient pulmonary work-up for an abnormal CT chest which showed mediastinal lymphadenopathy and complete collapse of the left lower lobe (LLL) without visualization of the LLL bronchus. She had been scheduled for an outpatient bronchoscopy, but was sent to the ED for worsening pleuritic pain before it could be performed. In the ED, she denied any fevers, shortness of breath, or productive cough. An inpatient bronchoscopy and endobronchial ultrasound was performed; however, no endobronchial lesions, mucus plugs, or abnormal lymph nodes were seen. Bronchoalveolar lavage with cell count, acid-fast bacillus, cultures, and cytology was unrevealing. The team later discovered that she had a chest x-ray in China from 2015 that reported a LLL consolidation. Given the chronicity, there was concern for pulmonary sequestration. A CT chest with IV contrast was performed, which showed a 7 x 4 x 4.6 mass-like consolidation in the LLL (Figure 1,2) with no separate arterial supply, which made pulmonary sequestration unlikely. However, the mass had multiple areas of cystic changes, characteristic of cystic adenomatoid malformation of the lung. She was referred to a cardiothoracic surgeon for resection. DISCUSSION: CCAMs are bronchopulmonary malformations that are usually unilateral without lobar preference. The etiology is unclear, but is usually seen in neonates. These malformations can be described as cystic, intermediate, or solid [2]. The most common presentation in adults is recurrent pulmonary infections [1]. Other presentations include pneumothoraces, hemoptysis, or dyspnea. CAM can also be found incidentally on imaging; therefore, highlighting the usefulness of reviewing old imaging if available [1]. CT angiography is the best technique for diagnosis because it can help differentiate CAM from other conditions, such as pulmonary sequestration. Surgical resection is the main treatment option in order to prevent recurrent infections. Additionally, CCAMs can become cancerous; therefore, resecting them reduces the chance of malignant transformation [3]. CONCLUSIONS: Although CAM is rarely seen in adults, it is important to keep it in the differential diagnosis for patients that present with recurrent pulmonary infections and unilateral cystic lesions of the lung. Reference #1: Herrero, Y., Pinilla, I., Torres, I., Nistal, M., Pardo, M., & Gómez, N. (2005). Cystic adenomatoid malformation of the lung presenting in adulthood. The Annals of thoracic surgery, 79(1), 326-329. Reference #2: Van Dijk, C., & Wagenvoort, C. A. (1973). The various types of congenital adenomatoid malformation of the lung. The Journal of Pathology, 110(2), 131-134. Reference #3: Granata, C., Gambini, C., Balducci, T., Toma, P., Michelazzi, A., Conte, M., & Jasonni, V. (1998). Bronchioloalveolar carcinoma arising in congenital cystic adenomatoid malformation in a child: a case report and review on malignancies originating in congenital cystic adenomatoid malformation. Pediatric pulmonology, 25(1), 62-66. DISCLOSURES: No relevant relationships by Sathya Alekhya Bukkuri no disclosure on file for Jerry Ipe; No relevant relationships by Henry Mayo-Malasky No relevant relationships by Mangalore Amith Shenoy No relevant relationships by Alexandra Zavin