Available via license: CC BY 4.0
Content may be subject to copyright.
Review began 12/07/2024
Review ended 12/19/2024
Published 12/19/2024
© Copyright 2024
Bertão et al. This is an open access article
distributed under the terms of the Creative
Commons Attribution License CC-BY 4.0.,
which permits unrestricted use, distribution,
and reproduction in any medium, provided
the original author and source are credited.
DOI: 10.7759/cureus.76023
Thoracic Hybrid Lesion: A Rare Case of Two
Congenital Malformations
Maria I. Bertão , Sara Fontaínhas , Rosário Santos Silva , Pedro Ramalho , Abílio Gonçalves
1. Internal Medicine, Hospital Distrital Figueira da Foz, Figueira da Foz, PRT 2. Pulmonology, Hospital Distrital
Figueira da Foz, Figueira da Foz, PRT
Corresponding author: Maria I. Bertão, mariainesbertao@gmail.com
Abstract
Cystic cuboid adenomatous malformations (CCAM) are congenital pulmonary lesions, usually benign, that
can progress into malignancy. Bronchopulmonary sequestration (BPS) is another type of malformation that
consists of an ectopic pulmonary tissue mass that doesn’t participate in blood-gas exchanges, with
vascularization provided by anomalous branches of the thoracic aorta.
Hybrid lesions are lesions that have histological features of CCAM but with systemic vascularization, a
pathognomonic sign of BPS. These lesions are rare and difficult to diagnose. The diagnoses are mostly made
in the pre-or neonatal phases of life. The diagnosis in adults is uncommon. The treatment is surgical
resection of the lesion or wedge lobectomy.
The case report describes a case of a hybrid lesion diagnosed in an asymptomatic adult, as well as a review of
the adequate diagnostic workup for pulmonary lesions. In the literature, there are few cases of congenital
lung lesions described in adults.
Categories: Internal Medicine
Keywords: bronchopulmonary sequestration, congenital abnormalities, cystic adenomatoid malformation of lung,
hybrid lesion, lung injury
Introduction
Cystic cuboid adenomatoid malformations (CCAM) are rare congenital lung lesions, first reported in the
literature in 1897 as pulmonary cysts in a newborns. It is a congenital disease, usually benign, which is
characterized by the excessive proliferation of adenomatous tissue of the bronchiolar epithelium, even
during embryogenesis, and can occur at different stages of lung development, leading to the development of
cysts. Some cases document evolution to malignancy [1-3].
Often these cysts are multiple and affect only one lung lobe. Five types are described according to the
Stocker classification (type 0 to IV), taking into account the different origins of the bronchial tree,
histopathological and clinical differentiation, malignant potential, and prognosis. Histologically, these
cystic lesions have predominantly elastic tissue and an absence of cartilage [1,2]. Cystic cuboid adenomatoid
malformations are supplied by pulmonary circulation through their connection to the tracheobronchial
tree [3].
Most of the time, the diagnosis of this entity is made in the neonatal or even prenatal period. However, its
diagnosis can be made later in childhood or rarely in adulthood. Clinically, the most typical presentation is
dyspnea or recurrent lobar pneumonia, but its diagnosis is sometimes incidental, through tests performed
for other reasons [1]. There seems to be an inflammatory component that is more notorious in older ages,
which is absent in the neonatal period [4]. The differential diagnosis should consider bronchogenic cysts,
bronchiectasis, and bronchopulmonary sequestration (BPS) [1].
Bronchopulmonary sequestration is another type of malformation, also uncommon. It consists of a mass of
ectopic, extra- or intralobar lung tissue, which does not participate in gas exchange, supplied by the
systemic circulation through abnormal arteries originating from the thoracic aorta (pathognomonic finding)
[1, 2, 5]. The left lower lobe is the predominantly affected site [2,5]. A distinctive radiological feature is the
fact that the mass is vascularized from the aorta and not from the pulmonary circulation, which can help in
the differential diagnosis with other pulmonary lesions or pathologies, such as complicated pneumonia. The
treatment of CCAM and BPS is surgical in both pathologies [2].
There are also congenital thoracic lesions, called hybrid lesions, which have histological characteristics of
CCAM but with vascularization from the systemic circulation, a pathognomonic sign of BPS. These lesions
are very rare and difficult to diagnose. According to the literature, it seems that this abnormal
vascularization confers a better prognosis for hybrid lesions when compared with CCAM, usually with
pulmonary supply [6].
1 1 1 2 1
Open Access Case Report
How to cite this article
Bertão M I, Fontaínhas S, Santos Silva R, et al. (December 19, 2024) Thoracic Hybrid Lesion: A Rare Case of Two Congenital Malformations.
Cureus 16(12): e76023. DOI 10.7759/cureus.76023
The diagnosis of these lesions is challenging, mainly due to the diversity of diagnostic hypotheses. The
etiology is diverse, but only 1% has the potential for malignancy. However, the dimensions, evolution,
location, presence of fat and calcification pattern, borders, and density of the pulmonary nodule are
characteristics to be considered in the evaluation. Computed tomography (CT) is the most appropriate test
for the diagnosis [7]. Although CT is a gold-standard test for the diagnosis and characterization of these
lesions, the tomographic pattern of a cystic malformation (type I can rarely be a precursor of
bronchoalveolar carcinoma) is indistinguishable from, for example, a bronchogenic cyst, requiring the
resection of any detected intrapulmonary cystic lesion [2,8].
Case Presentation
This case report is about a Caucasian female patient who was previously autonomous. No known significant
medical history. Usually medicated with ethinylestradiol and gestodene. The patient went to the emergency
department for 24 hours of evolution of suprapubic pain and pain in the right lumbar region, of nonspecific
characteristics, without irradiation, with partial cessation to paracetamol. In addition, she reported an
impression of pyrexia, without quantitative assessment of body temperature, holocranial headaches,
nausea, dyspareunia, and spotting in the last months. She described previous conditions similar to those
that motivated three previous visits to the emergency department with a diagnosis of recurrent urinary tract
infections (UTI), the last in the previous month, having been medicated with norfloxacin. She denied
vomiting, dysuria, pollakiuria, or hematuria.
In the clinical evaluation, on objective examination, the patient was febrile (tympanic temperature 38.8ºC),
normotensive, and with sinus tachycardia. Cardiopulmonary auscultation showed no abnormalities.
Abdominal examination revealed pain on palpation of the lower quadrants, with doubtful renal Murphy on
the right, analytically highlighting a slight lymphocytopenia and elevation of C-reactive protein (Table 1).
Summary urine examination with leukocyturia, without nitrites, and moderate bacterial proliferation in the
sediment and cultural examination of urine with polymicrobial flora.
Parameter Value/Result Reference values
Leukocytes 5.20 x103 /µL 4.00-10.50 x103 /µL
Neutrophils 4.52 x103 /µL 1.50-6.60 x103 /µL
Lymphocytes 0.38 x103 /µL 1.50-3.50 x103 /µL
Monocytes 0.23 x103 /µL 0.00-1.00 x103 /µL
Eosinophils 0.05 x103 /µL 0.00-0.70 x103 /µL
Basophils 0.03 x103 /µL 0.00-0.10 x103 /µL
Hemoglobin 13.5 g/dL 12.5-16.0 g/dL
Hematocrit 40.5 % 37.0-47.0 %
MCV 100.0 fL 78.0-100.0 fL
MCHC 33.4 g/dL 32.0-36.0 g/dL
Platelets 175x103 /µL 150-450 x103 /µL
ALT 10 U/L 0-31 U/L
AST 13 U/L 0-32 U/L
ALP 56 U/L 35-104 U/L
LDH 303 U/L <250 U/L
GGT 14 U/L 5-36 U/L
Total
bilirubin 0.50 mg/dL <1.0 mg/dL
Direct
bilirubin 0.20 mg/dL 0.00-0.30 mg/dL
Blood
glucose 111 mg/dL 74-106 mg/dL
2024 Bertão et al. Cureus 16(12): e76023. DOI 10.7759/cureus.76023 2 of 6
Urea
nitrogen
8.5 mg/dL 8.0-23.0 mg/dL
Creatinine 0.5 mg/dL 0.5-0.9 mg/dL
Sodium 137 mEq/L 136-145 mEq/L
Potassium 4.2 mEq/L 3.5-5.1 mEq/L
Chloride 100 mEq/L 96-107 mEq/L
CRP 99.30 mg/L <5 mg/L
Urinalysis
(Type II)
pH 6.5; density 1.019; proteins negative; glucose normal; acetone negative; urobilinogen normal; bilirubin pigments
negative; blood 25 erythrocytes/ µL; leukocytes 500/µ; nitrites negative
Urinary
sediment Rare epithelial cells; leukocytes >20/field; erythrocytes 3-6/field; some bacterial proliferation
Urine culture Bacteriuria with CFU >10^5/mL; polymicrobial flora
Blood
cultures 3 negative samples
TABLE 1: Laboratory findings
MCV: mean corpuscular volume; MCHC: mean corpuscular hemoglobin concentration; ALT: alanine aminotransferase; AST: aspartate aminotransferase;
ALP: alkaline phosphatase; LDH: lactate dehydrogenase; GGT: gamma-glutamyl transferase; CRP: C-reactive protein; CFU: colony-forming units
Given the history of recurrent UTIs in the last few months and a suggestive clinical picture, she underwent
abdominopelvic CT to exclude structural pathology or signs of complication. CT scans showed a nodular,
multilocular lesion with lobulated contours, thickened walls, and pleural contact in the left lower lung lobe.
A follow-up thoracic CT scan, conducted to rule out a lung abscess, revealed a 75x60mm cystic lesion with
small internal calcifications and no evident bronchial branches, consistent with BPS (Figure 1).
FIGURE 1: Nodular lesion with pleural contact in the left lower lung lobe
Multiloculated, lobulated cystic lesion, measuring 75x60 mm, with a small calcification in its inner aspect in the left
lower lung lobe (red arrow).
The likely urinary infection was treated with clinical and analytical improvement. She was discharged with
oral antibiotic therapy after four days of hospitalization, with no complications during this period. For the
study of the lung lesion, a chest X-ray (Figure 2) was also performed, and a CT-guided transthoracic biopsy
was scheduled, which was carried out without complications, approximately one month after discharge from
the hospital.
2024 Bertão et al. Cureus 16(12): e76023. DOI 10.7759/cureus.76023 3 of 6
FIGURE 2: Left lateral chest X-ray obtained prior to the transthoracic
biopsy
The lesion is marked with the red arrow.
The result of the transthoracic biopsy was histologically inconclusive, and it was a connective tissue lesion
with chronic inflammatory involvement, without specificity criteria and representation of lung parenchyma.
After formal evaluation by cardiothoracic surgery, she underwent wedge resection of the left lower lobe.
During the surgical procedure, an abnormal artery, originating from the descending thoracic aorta, was
observed to supply the lesion, a pathognomonic presentation of BPS. The histology of the lesion was
consistent with cystic adenomatoid malformation type III. Favorable postoperative evolution, with no
complications associated with pulmonary surgery. Clinically asymptomatic and without evidence of the
lesion on imaging reassessment (Figure 3). She was discharged from the consultation after a 12-month
follow-up.
FIGURE 3: Postoperative left lateral chest X-ray without evidence of the
lesion
Discussion
Reviewing the literature published to date, there are numerous descriptions of hybrid lesions across the
spectrum of pediatric age and during the prenatal period. However, it was only in 2010 that Scialpi et al.
described, among other cases, the case of a 75-year-old adult with complaints of dyspnea, who presented
with a hybrid lesion of intralobar BPS associated with CCAM type I [8]. About a decade later, Hamanaka et.
al. published a review of 60 cases of CCAM in adults, including the case described in 2010, which was the
2024 Bertão et al. Cureus 16(12): e76023. DOI 10.7759/cureus.76023 4 of 6
only one with a hybrid lesion [1].
This case demonstrates the asymptomatic presentation of hybrid lesions. The patient presented to the
emergency department for an entirely unrelated issue, confirming the accidental nature of this diagnosis in
adulthood, although it can alternatively present with symptoms of recurrent respiratory infections and
pulmonary hemorrhage [9]. The discovery of a pulmonary lesion in a young patient prompted diagnostic
investigation. Since the biopsy was inconclusive, surgical intervention was required, significantly impacting
her life, with the final diagnosis only confirmed through this approach. Hybrid lesions are rare pulmonary
conditions that combine features of both congenital pulmonary airway malformation and BPS, with most
diagnoses occurring in the pre-or neonatal period, making their identification in adulthood even more
uncommon [10,11]. The diagnostic process presents challenges, with a broad differential diagnosis. The
indolent progression of this lesion, aligned with existing literature suggesting a better prognosis for hybrid
lesions, is further supported by the fact that these lesions are typically treated surgically within the first year
of life and have an excellent prognosis [11]. Lesions with malignant features can be benign, and although
rare, the reverse can also occur [12]. As shown in the literature and this case, surgical resection is essential
for optimal outcomes. Hybrid operations are safer and more comprehensive, with the exact localization of
such lesions often only identified during surgical exploration [13-15].
Conclusions
This case also stands out for its benignity throughout the course of the pathology. The initial hypothesis of
lung abscess was raised due to the patient's recurrence of healthcare required, high fever, and the
radiological characteristics of the initial CT scan, which reported enhancement of the lesion wall. The totally
asymptomatic presentation until the incidental imaging finding, despite being a lesion with considerable
dimensions, is not the most common evolution of this pathology, often associated with recurrent respiratory
infections, spontaneous pneumothorax, or chronic respiratory failure. The indolent evolution of this lesion,
however, corroborates the previous data in the literature on a better prognosis for hybrid lesions.
Additional Information
Author Contributions
All authors have reviewed the final version to be published and agreed to be accountable for all aspects of the
work.
Concept and design: Maria I. Bertão, Sara Fontaínhas, Rosário Santos Silva, Abílio Gonçalves, Pedro
Ramalho
Acquisition, analysis, or interpretation of data: Maria I. Bertão, Sara Fontaínhas, Rosário Santos Silva,
Abílio Gonçalves, Pedro Ramalho
Drafting of the manuscript: Maria I. Bertão, Sara Fontaínhas, Rosário Santos Silva, Abílio Gonçalves,
Pedro Ramalho
Critical review of the manuscript for important intellectual content: Maria I. Bertão, Sara Fontaínhas,
Rosário Santos Silva, Abílio Gonçalves, Pedro Ramalho
Supervision: Maria I. Bertão, Sara Fontaínhas, Rosário Santos Silva, Abílio Gonçalves, Pedro Ramalho
Disclosures
Human subjects: Consent for treatment and open access publication was obtained or waived by all
participants in this study. Conf licts of interest: In compliance with the ICMJE uniform disclosure form, all
authors declare the following: Payment/services info: All authors have declared that no financial support
was received from any organization for the submitted work. Financial relationships: All authors have
declared that they have no financial relationships at present or within the previous three years with any
organizations that might have an interest in the submitted work. Other relationships: All authors have
declared that there are no other relationships or activities that could appear to have influenced the
submitted work.
Acknowledgements
The authors would like to thank Dr. Ivo Barreiro for his collaboration in the case.
References
1. Hamanaka R, Yagasaki H, Kohno M, Masuda R, Iwazaki M: Congenital cystic adenomatoid malformation in
adults: report of a case presenting with a recurrent pneumothorax and a literature review of 60 cases. Respir
Med Case Rep. 2019, 26:328-32. 10.1016/j.rmcr.2018.02.002
2. Mehta PA, Sharma G: Congenital Pulmonary Airway Malformation . StatPearls [Internet], StatPearls
2024 Bertão et al. Cureus 16(12): e76023. DOI 10.7759/cureus.76023 5 of 6
Publishing, Treasure Island, FL; 2024.
3. Greenspon A, Samuels L, Greenspon L: Extralobar sequestration complicated by a cystic hamartoma in an
adult. Ann Thorac Surg. 2019, 108:e43-4. 10.1016/j.athoracsur.2018.10.072
4. Lackner RP, Thompson AB 3rd, Rikkers LF, Galbraith TA: Cystic adenomatoid malformation involving an
entire lung in a 22-year-old woman. Ann Thorac Surg. 1996, 61:1827-9. 10.1016/0003-4975(95)01197-8
5. Amos LB: Cough. Nelson Pediatric Symptom-Based Diagnosis. Kliegman RM, Lye PS, Bordini BJ, Toth H,
Basel D (ed): Elsevier, New York City, NY; 2017. 15-38. 10.1016/B978-0-323-39956-2.00002-9
6. Cass DL, Crombleholme TM, Howell LJ, Stafford PW, Ruchelli ED, Adzick NS: Cystic lung lesions with
systemic arterial blood supply: a hybrid of congenital cystic adenomatoid malformation and
bronchopulmonary sequestration. J Pediatr Surg. 1997, 32:986-90. 10.1016/s0022-3468(97)90383-3
7. Weinberger SE, McDermontt S: Diagnostic evaluation of the incidental pulmonary nodule . UpToDate. Post
TW (ed): UpToDate, Waltham, MA; 2024.
8. Scialpi M, Cappabianca S, Rotondo A, et al.: Pulmonary congenital cystic disease in adults. Spiral computed
tomography findings with pathologic correlation and management . Radiol Med. 2010, 115:539-50.
10.1007/s11547-010-0467-6
9. Mestas Nuñez M, Dulcich G, Restrepo CS, et al.: Congenital lung anomalies in adults . Radiographics. 2024,
44:e240017. 10.1148/rg.240017
10. Klein JD, Turner CG, Dobson LJ, Kozakewich H, Jennings RW: Familial case of prenatally diagnosed
intralobar and extralobar sequestrations with cystadenomatoid change. J Pediatr Surg. 2011, 46:e27-31.
10.1016/j.jpedsurg.2010.10.027
11. Hardee S, Tuzovic L, Silva CT, Cowles RA, Copel J, Morotti RA: Congenital cystic lung lesions: evolution
from in-utero detection to pathology diagnosis-a multidisciplinary approach. Pediatr Dev Pathol. 2017,
20:403-10. 10.1177/1093526617698604
12. Roggin KK, Breuer CK, Carr SR, et al.: The unpredictable character of congenital cystic lung lesions . J Pediatr
Surg. 2000, 35:801-5. 10.1053/jpsu.2000.6088
13. Zhou H, Tang S, Fu Q, Yu L, Liu L: Hybrid surgery in treatment of pulmonary sequestration with abdominal
aorta feeding vessel: a case report. J Cardiothorac Surg. 2018, 13:44. 10.1186/s13019-018-0733-6
14. Olivieri C, Nanni L, Busato G, Rindi G, Marano R, Pintus C: Intradiaphragmatic hybrid lesion in an infant:
case report. J Pediatr Surg. 2012, 47:e25-8. 10.1016/j.jpedsurg.2012.04.010
15. Pumberger W, Hörmann M, Deutinger J, Bernaschek G, Bistricky E, Horcher E: Longitudinal observation of
antenatally detected congenital lung malformations (CLM): natural history, clinical outcome and long-term
follow-up. Eur J Cardiothorac Surg. 2003, 24:703-11. 10.1016/j.ejcts.2003.08.001
2024 Bertão et al. Cureus 16(12): e76023. DOI 10.7759/cureus.76023 6 of 6
