Background: Pulmonary sequestration (PS) is a form of congenital pulmonary malformation that is generally diagnosed in childhood or adolescence and usually resected when diagnosed. We aim to identify the clinical presentation and course of patients diagnosed to have PS during adulthood. Methods: Using a computer-assisted search of Mayo clinic medical records, we identified adult patients with PS diagnosed between 1997 and 2016. Clinical and radiological data were collected including postoperative course for those who underwent surgical resection. Results: We identified 32 adult patients with PS; median age at diagnosis was 42 years (IQR 28–53); 17 patients (53%) were men. The median sequestration size was 6.6 cm (IQR 4.4–9.3). The type of sequestration was intralobar in 81% and extralobar in 19%. The most common location was left lower lobe posteromedially (56%). Forty-seven percent of the patients presented with no relevant symptoms. The most common radiographic finding was mass/ consolidation in 61% and the most common feeding artery origin was the thoracic aorta (54%). Surgical resection was performed in 18 patients (56%) and postoperative complication was reported in 5 patients (28%). There was no surgical mortality. Median duration of follow-up after diagnosis for unresected cases, most of whom were asymptomatic, was 19 months (IQR 4–26) with no complications related to the PS reported. Conclusions: Nearly one-half of adult patients with PS present with no relevant symptoms. The decision regarding surgical resection needs to weigh various factors including clinical manifestations related to PS, risk of surgical complications, comorbidities, and individual patient preferences. Keywords: Pulmonary sequestration Background undetected during the prenatal period and early child- Pulmonary sequestration (PS) is a congenital lung mal- hood years . formation that consists of a nonfunctioning lung tissue The PS is divided into two types, intralobar sequestra- with no apparent communication with the tracheobron- tion (ILS) which is the more common type, where the chial tree . The blood supply to PS is through aber- lesion lies within pleural layer surrounding the lobar rant vessels from systemic circulation, most commonly lung and extralobar sequestration (ELS) which has its the descending thoracic aorta. The term sequestration is own pleural covering, maintaining complete anatomic derived from the Latin verb sequestare, which means ‘to separation from adjacent normal lung . separate’ and it was first introduced as a medical term Most patients with ILS present in adolescence or early by Pryce in 1964 [2, 3]. PS is rare, representing about 1 adulthood with recurrent pneumonias in the affected to 6% of all congenital lung anomalies and may go lobe . Patients with PS can be asymptomatic and the diagnosis achieved incidentally. Other presenting symp- toms may include cough, hemoptysis, chest pain and dyspnea [6, 7]. ELS rarely becomes infected because it is * Correspondence: firstname.lastname@example.org Division of Pulmonary and Critical Care Medicine, Gonda 18 South, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA © The Author(s). 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Alsumrain and Ryu BMC Pulmonary Medicine (2018) 18:97 Page 2 of 5 separated from the tracheobronchial tree by its own Table 1 Type and location of pulmonary sequestration (n = 32) pleural investment . Characteristic Number of patients (%) There are multiple radiologic manifestations of PS on Type of sequestration computed tomography (CT) which include mass, con- Intralobar 26 (81) solidation with or without cysts, bronchiectasis and cavi- Extralobar 6 (19) tary lesions [4, 7]. Hyperlucency can be seen in ILS due Location to the entrance of air from the collateral drift from nor- Left lower lobe 18 (56) mal lung resulting in air trapping . The arterial supply to PS is most commonly from the thoracic aorta as de- Posteromedial 18 (56) scribed for 74% of cases reported by Savic et al. in a re- Right lower lobe 14 (44) view of 540 published cases . The supplying artery Posteromedial 13 (41) may also arise from the abdominal aorta, celiac artery, Anterior 1 (3) splenic artery or even a coronary artery . Most ILS drains to pulmonary veins while venous drainage for most ELS is to the azygos or hemiazygos vein or to the Results inferior vena cava [4, 8]. We identified 32 adult patients with PS whose median Most of the data pertaining to PS are from the age was 42 years (IQR 28–53); 17 patients (53%) were pediatrics literature. Occasionally, PS may be diagnosed men. The median sequestration size was 6.6 cm (IQR for the first time in adulthood [6, 9, 10]. Due to paucity 4.4–9.3). The type of sequestration was intralobar in of published data, natural history and optimal manage- 81% and extralobar in 19%. The most common location ment of PS diagnosed in adults remain unclear. Further- was left lower lobe posteromedially (56%) (Table 1). The more, the outcome of adult patients with unresected PS most common presenting symptom was cough (34%); is not known. Thus, we aimed to explore the clinical however, 15 (47%) had no relevant symptoms (Table 2). presentation and course of adult patients with PS includ- Other presenting symptoms included dyspnea, thoracic ing those who do not undergo surgical resection. pain, and hemoptysis. Recurrent respiratory infections were a presenting complaint in 16% of the patients. Asymptomatic patients had PS detected incidentally on Methods chest imaging studies. Using a computer-assisted search of Mayo clinic medical The most common radiologic finding was mass/con- records, we identified 32 adults (age 18 or greater) who solidation in 61% followed by hyperlucency in 42%; cys- were first diagnosed to have PS between 1997 and 2016. tic changes were noted in 23% (Table 3) (Fig. 1). Dilated Mayo Clinic Institutional Review Board approval was bronchi were seen in 15% and mixed radiologic features obtained (#17–002077). The diagnosis was confirmed in were in 34% of the patients. The most common feeding all resected cases by histopathologic examination and artery origin was the thoracic aorta (54%); others include the non-resected cases were diagnosed by imaging char- abdominal aorta (23%), celiac (11%) and inferior acteristics including the presence of anomalous systemic phrenic/left gastric (4%). The origin of the feeding artery arterial supply identified by thoracic radiologists. Among was not specifically identified in 2 cases (8%) both of the resected cases we didn’t encounter hybrid lesion of which were resected. congenital pulmonary airway malformation (congenital Surgical resection was performed in 18 patients (56%). cystic adenomatoid malformation) and PS. The most common indication for surgery was recurrent Available medical records and imaging studies were respiratory infections in 12 (66%) followed by reviewed to confirm the diagnosis of PS. Clinical and radiological data were collected including postoperative Table 2 Presenting symptoms (n = 32) course in those who underwent surgical resection and Characteristic Number of patients (%) the clinical course of those who did not undergo surgical Cough 11 (34) resection. Chest/back pain 5 (16) Dyspnea 5 (16) Statistical methods Fever 5 (16) Data were presented as median and interquartile range Recurrent respiratory infections 5 (16) (IQR) for continuous variables and counts and percentages Hemoptysis 3 (9) for categorical variables. For comparisons Mann-Whitney U Right upper abdominal pain 2 (6) test was used for continuous variables and Fischer exact test Asymptomatic 15 (47) for categorical variables. Two-side p-value < 0.05 was con- sidered statistically significant. Note: one patient may have more than one symptom Alsumrain and Ryu BMC Pulmonary Medicine (2018) 18:97 Page 3 of 5 Table 3 Radiologic manifestations (n = 26) hemoptysis and pleural effusion in one patient each (Table 4). Four remaining patients underwent surgery Radiologic manifestations Number of patients (%) for an asymptomatic lung lesion suspected to be PS. Mass/consolidative 16 (61) Sub-lobar resection was done in 13 (8 ILS, 5 ELS) of 18 Hyperlucency 11 (42) (72%) and the remaining five patients underwent lobec- Cystic changes 6 (23) tomies (all ILS). Postoperative complications were re- Dilated bronchi 4 (15) ported in 5 patients (28%; 4 ILS, 1 ELS) and included Mixed features 9 (34) chylous leak, intraoperative mild bleeding, chronic chest Feeding artery pain, arm numbness and pneumonia. Two of these 5 pa- tients who experienced postoperative complications had Thoracic Aorta 14 (54) been asymptomatic in regard to their lung lesion Abdominal Aorta 6 (23) preoperatively. Celiac 3 (11) There was no significant difference in age, gender or Inferior phrenic/left gastric 1 (4) sequestration size between surgical and non-surgical pa- Not determined 2 (8) tients. However, surgical patients were more often symp- Venous drainage tomatic at presentation compared to non-surgical (78% Pulmonary veins 8 (30) vs 29%, P = 0.011) (Table 5). There was no surgical mor- Azygos vein 2 (8) tality (in-hospital). Follow-up data after diagnosis were available in 9 unre- Hemiazygos vein 1 (4) sected cases and 17 resected cases; the median duration of Left atrium 2 (8) follow-up was 19 months (IQR 4–26) and 2.5 months Not determined 13 (50) (IQR 1–143), respectively, with no complications related CT available for current review in 26 patients b to the sequestration reported during follow up. These two patients underwent surgery resection of pulmonary sequestration but exact origin of the feeding artery was not identified on CT Discussion In this retrospective review of 32 cases of PS diagnosed in adults over a 20-year period in a tertiary care center, Fig. 1 a: Pulmonary sequestration (intralobar) presenting as a multi-cystic lesion in the postero-basal segment of the left lower lobe. b: Pulmonary sequestration (extralobar) presenting as extra-pulmonary mass in the right paravertebral region. c: Pulmonary sequestration (intralobar) presenting as an area of hyperlucency and dilated bronchus filled with mucus in the right lower lobe. d: Left lower lobe sequestration (intralobar) presenting as a mass in the left lower lobe with feeding artery from descending aorta Alsumrain and Ryu BMC Pulmonary Medicine (2018) 18:97 Page 4 of 5 Table 4 Surgical management data (n = 18) referable to the presence of PS and no relevant symp- toms or events occurred during follow-up of patients Number of patients (%) with unresected PS. Indication for surgery Petersen et al. reviewed the literature for patients Recurrent pulmonary infections 12 (66) above the age of 40 with ILS and found 15 cases includ- Hemoptysis 1 (6) ing two patients from their own medical center . Most Pleural effusion 1 (6) of these adult patients underwent surgical resection of Asymptomatic lung lesions 4 (22) their ILS. The largest study in the literature on PS is Type of resection from China where Wei et al. reported 2625 cases of PS including 132 adult patients. However, their report does Thoracotomy not describe how many of their adult PS patients under- Lobectomy 1 (6) went surgical resection, associated surgical outcome, nor Segmentectomy/sequestrectomy 3 (17) clinical course of patients who did not undergo surgical Wedge resection 2 (11) resection . In a study by Makhija et al., 102 older pa- VATS tients (age 4 to 80 years) with congenital cystic lung dis- Lobectomy 4 (22) ease undergoing surgical management were reported and included 20 with PS (20%); postsurgical complica- Segmentectomy/sequestrectomy 6 (33) tion rate of 9.8% for the entire cohort was reported . Wedge resection 2 (11) Berna et al. studied 26 adult patients with ILS all of VATS Video-assisted thoracoscopy (VATS) whom underwent surgical resection . Hemoptysis or we found that 56% of the patients underwent surgical re- recurrent infection was present in 54%. All 26 patients section. The patients who underwent surgery were more underwent surgical resection of their PS including 20 likely to be symptomatic compared to those who did patients (77%) who underwent lobectomies. Postopera- not. Surgical resection of PS was associated with a post- tive complication rate was 25% and included pleural em- operative complications rate of 28%. The median follow pyema, hemoptysis, prolonged air leak, arrhythmia, and up duration was 19 months for the non-surgical group, fistulae. All patients were alive and well at long-term and no complications related to the sequestration were follow-up (mean 36.5 months). reported during the follow up period. In our cohort, 56% of patients underwent surgical re- Nearly one-half of the adult patients diagnosed with section for various indications; the most common indi- PS manifested no relevant symptoms. It has been gener- cation was recurrent respiratory infection although it ally believed that most patients should have their PS was often difficult to prove the relationship between resected even if they are asymptomatic due to concerns those infections and the sequestration. None of our pa- regarding eventual complication, mainly infection of PS. tients had experienced massive hemoptysis and only However, this issue remains debatable since data regard- three patients (9%) described mild hemoptysis. ing the long-term clinical course and outcome of those The surgical resection of sequestration carries the risk with unresected PS are sparse, particularly in the adult of complications; the surgical complication rate in our population. Our study cohort included adults in their cohort was 28% which included chylous leak, intraopera- third to seventh decades of life without symptoms tive mild bleeding, chronic chest pain, arm numbness Table 5 Comparison of surgical vs non-surgical patients Characteristics Surgical (n = 18) Nonsurgical (n = 14) P-value Age, median (IQR) 41 (27–50) 43 (33–68) 0.218 Sex, n (%) 0.087 Male 7 (39) 10 (71) Female 11 (61) 4 (29) Sequestration Size, median (IQR) 6.5 (4–7) 6 (3.4–8.9) 0.778 Type of sequestration, n (%) 0.196 Intralobar 13 (72) 13 (93) Extralobar 5 (28) 1 (7) Presenting symptoms, n (%) 0.011 Asymptomatic 4 (22) 10 (71) Symptomatic 14 (78) 4 (29) Alsumrain and Ryu BMC Pulmonary Medicine (2018) 18:97 Page 5 of 5 and pneumonia. No surgical mortality occurred. These 6. Petersen G, Martin U, Singhal A, Criner GJ. Intralobar sequestration in the middle-aged and elderly adult: recognition and radiographic evaluation. results are similar to those reported by Berna et al . Journal of Thoracic & Cardiovascular Surgery. 2003;126(6):2086–90. There are limitations to this study. The retrospective 7. Wei Y, Li F. Pulmonary sequestration: a retrospective analysis of 2625 cases nature of this study limited the extent of data that could in China. Eur J Cardiothorac Surg. 2011;40(1):e39–42. 8. Savic B, Birtel FJ, Tholen W, Funke HD, Knoche R. Lung sequestration: report be retrieved including preceding symptoms and the of seven cases and review of 540 published cases. Thorax. 1979;34(1):96– exact relationship to the PS. The number of study sub- jects was modest due to the rarity of PS encountered in 9. Hirai S, Hamanaka Y, Mitsui N, Uegami S, Matsuura Y. Surgical treatment of infected intralobar pulmonary sequestration: a collective review of patients the adult population. Nonetheless, our data provide add- older than 50 years reported in the literature. Annals of Thoracic & itional insight beyond what is currently available in the Cardiovascular Surgery. 2007;13(5):331–4. literature regarding the clinical course of PS in adults, 10. Montjoy C, Hadique S, Graeber G, Ghamande S. Intralobar bronchopulmonary sequestra in adults over age 50: case series and review. particularly those who choose not to undergo surgical W V Med J. 2012;108(5):8–13. resection. 11. Berna P, Cazes A, Bagan P, Riquet M. Intralobar sequestration in adult patients. Interactive Cardiovascular & Thoracic Surgery. 2011;12(6):970–2. Conclusions Nearly one-half of adult patients with pulmonary se- questration present with no relevant symptoms. The de- cision regarding surgical resection needs to weigh various factors including clinical manifestations related to PS, risk of surgical complications, comorbidities, and individual patient preferences. Abbreviations CT: Computed tomography; ELS: Extralobar sequestration; ILS: Intralobar sequestration; IQR: Interquartile range; PS: Pulmonary sequestration Availability of data and materials The datasets analyzed during the current study are available from the corresponding author on reasonable request. Authors’ contributions MA contributed to data abstraction and analysis and manuscript writing. JHR contributed to the conceptualization and design of the study and manuscript writing. MA and JHR are guarantors of this work. All authors read and approved the final manuscript. Ethics approval and consent to participate Mayo Clinic Institutional Review Board approval was obtained (#17–002077). Competing interests Authors declare no competing interests related to this study. Publisher’sNote Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Received: 2 June 2017 Accepted: 29 May 2018 References 1. Liechty KW, Flake AW. Pulmonary vascular malformations. Semin Pediatr Surg. 2008;17(1):9–16. 2. Corbett HJ, Humphrey GME. Pulmonary sequestration. Paediatr Respir Rev. 2004;5(1):59–68. 3. Pryce DM. Lower accessory pulmonary artery with intralobar sequestration of lung; a report of seven cases. J Pathol Bacteriol. 1946;58(3):457–67. 4. Walker CM, Wu CC, Gilman MD, Godwin JD, 2nd, Shepard J-AO, Abbott GF: The imaging spectrum of bronchopulmonary sequestration. Curr Probl Diagn Radiol 2014, 43(3):100–114. 5. Makhija Z, Moir CR, Allen MS, Cassivi SD, Deschamps C, Nichols FC 3rd, Wigle DA, Shen KR. Surgical management of congenital cystic lung malformations in older patients. Ann Thorac Surg. 2011;91(5):1568–73. discussion 1573
BMC Pulmonary Medicine – Springer Journals
Published: Jun 5, 2018
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud