
==== Front
Indian J Nucl Med
Indian J Nucl Med
IJNM
Indian J Nucl Med
Indian Journal of Nuclear Medicine : IJNM : The Official Journal of the Society of Nuclear Medicine, India
0972-3919
0974-0244
Wolters Kluwer - Medknow India

IJNM-39-213
10.4103/ijnm.ijnm_29_24
Case Report
Mediastinal Hemangioma Mimicking as Bronchial NET
Kar Siven
Gupta Harshita
Shaikh Nusrat
Lele Vikram
Department of Nuclear Medicine and PET/CT, Jaslok Hospital and Research Centre, Mumbai, Maharashtra, India
Address for correspondence: Dr. Siven Kar, Department of Nuclear Medicine and PET/CT, Jaslok Hospital and Research Centre, Mumbai, Maharashtra, India. E-mail: siven.kar@gmail.com
May-Jun 2024
17 8 2024
39 3 213215
05 3 2024
13 4 2024
13 4 2024
Copyright: © 2024 Indian Journal of Nuclear Medicine
2024
https://creativecommons.org/licenses/by-nc-sa/4.0/ This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms.
We present a rare case of mediastinal capillary hemangioma in a 54-year-old female. She presented with back pain in the left suprascapular region, and the chest radiograph revealed left pleural effusion. On further workup with high-resolution computed tomography (CT) chest, a hypervascular pleural-based neoplastic lesion in the left upper hemithorax with gross left pleural effusion and subtotal collapse of the left lung was identified. 18F-fluorodeoxyglucose positron emission tomography/CT was suggestive of a weakly metabolic well-defined pleural-based soft tissue lesion in the left upper hemithorax along the mediastinal side. Neuroendocrine tumor was suspected. 68Ga-DOTATATE PET/CT was advised, which showed intense uptake in the lesion. The mass was resected completely. Histopathological examination established the final diagnosis as benign vascular tumor consistent with a capillary hemangioma.

68Ga-DOTATATE positron emission tomography/computed tomography
capillary hemangioma
mediastinal carcinoid
mediastinal mass
neuroendocrine tumor
pleural effusion
==== Body
pmcIntroduction

Somatostatin receptor (SSTR) scintigraphy is an established modality for imaging well-differentiated neuroendocrine tumors (NETs). It is known that nonmalignant inflammatory diseases (e.g., tuberculosis) may also accumulate SSTR analogs. Mediastinal hemangioma showing intense SSTR expression and mimicking NET has not been reported earlier to the best of our knowledge. We report a case of mediastinal capillary hemangioma manifesting as pleural effusion, successfully managed by surgical excision.

Case Report

A 54-year-old female presented to the outpatient department with the complaints of the left upper back pain for 4 months, initially relieved on conservative management. On recurrent and nonrelieving symptoms, she underwent a chest X-ray. Chest X-ray revealed large left-sided pleural effusion, for which pleural tapping was done. On needle thoracocentesis, straw-colored fluid was aspirated. Evaluation of pleural fluid cytology was negative for malignant cells. Single-phase contrast-enhanced computed tomography (CT) revealed a hypervascular pleural-based neoplastic lesion in the left hemithorax with gross left pleural effusion and subtotal collapse of the left lung. Noncontrast 18F-fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET-CT) was suggestive of a weakly metabolically active well-defined soft tissue nodular lesion in the left upper hemithorax along the mediastinal side, and NET was suspected [Figure 1].

Figure 1 18F-fluorodeoxyglucose positron emission tomography/computed tomography maximum intensity projection and axial (a) and coronal (b) showing a weakly metabolically active pleural-based soft tissue mass in the left hemithorax

68Ga-DOTATATE PET/CT was advised, which showed intensely increased SSTR expression in a well-defined heterogeneously enhancing pleural-based soft tissue nodular lesion in the left upper hemithorax, with areas of necrosis within [Figure 2]. It measured 4.3 cm × 3.6 cm in the maximum transverse dimensions and 5 cm in superoinferior extent, primary NET was suspected and histopathological correlation was advised.

Figure 2 68Ga-DOTATATE positron emission tomography/computed tomography maximum intensity projection and axial (a) and coronal and sagittal (b) showing intense somatostatin receptor expression in a well-defined heterogeneously enhancing pleural-based soft tissue nodular lesion in the left upper hemithorax, with areas of necrosis within

The patient was planned for surgical excision and underwent thoracotomy with complete excision of the lesion with decortication and mediastinal lymph node excision (level 5 and level 9). Postoperative recovery period was uneventful. Postoperative chest radiograph showed minimal left pneumothorax.

Gross pathological examination of the tumor showed well-circumscribed lobulated neoplasm. Microscopic examination revealed many capillary sized, dilated, and congested thin-walled vessels lined by a single layer of endothelial cells and few large caliber arterial blood vessels. Many vessels showed fibrin thrombi. There was no evidence of significant atypia or mitotic activity. The stroma was edematous and showed areas of hemorrhage and occasional hemosiderin-laden macrophages. Immunohistochemistry was performed; endothelial cells expressed CD34, FLI-1, and Erythroblast transformation-specific [ETS]-related gene (ERG). The Mib 1 labeling index was 8%–10%. These findings were suggestive of benign vascular tumor consistent with a capillary hemangioma [Figure 3].

Figure 3 Microscopy images scanner view. (a) Admixture of varying sized vessels, high-power view. (b) Anastomosing capillary sized vascular channels and immunohistochemistry. (c) Endothelial cells staining positively with CD34

The patient was followed up in the outpatient department and was doing well.

Discussion

Hemangiomas are benign vascular tumors resulting from abnormal growth of blood vessels. They are proliferation of blood vessels of varying diameters with thin and uniform fibromuscular walls and lined by a single layer of benign cuboidal epithelium. They have varying amounts of stromal elements (e.g., fibrous tissue, fat, and myxoid elements).

Mediastinal hemangiomas are rare tumors, constituting <0.5% of all the mediastinal masses.[12] They share common histological subtypes with other vascular tumors in the body. These could be capillary, cavernous, venous, arteriovenous malformation, angiofibroma, angiolipoma, glomus tumor, hemangioendothelioma, and hemangiopericytoma. True hemangiomas are benign, but these should be differentiated from potentially malignant vascular tumors such as hemangioendothelioma and hemangiopericytoma via histological examination. Overall capillary and cavernous types account for >90% of the cases.[3]

These typically occur in young patients (<35 years accounting for 75% of the cases).[2] Approximately 50% of the cases are asymptomatic and detected incidentally, while others present with nonspecific complaints of cough, chest pain, fever, dyspnea (as a result of compression of adjacent structures), respiratory distress, hemoptysis, and superior vena cava syndrome.[145] They can be classified further based on their location, into anterior (most common), middle or posterior mediastinum.[6]

Typical CT findings include heterogeneously enhancing, hypervascular, well-circumscribed mass, with occasional case reports of infiltrative appearance. Multiple punctuate calcifications and phleboliths can be seen in 21% and 7% of cases, respectively. A study by McAdams et al. showed four distinct patterns of heterogeneous attenuation: central, mixed central and peripheral, peripheral, and nonspecific increased attenuation.[7] Chest CT is useful in assessing the extent of the lesion before planning for surgical intervention. Magnetic resonance imaging could be useful; however, no preoperative investigations are diagnostic.

Other differentials such as Castleman disease, paraganglioma, vascular malformation, ectopic parathyroid adenoma, and hypervascular metastasis should be considered when hypervascular anterior mediastinal masses are encountered.[6]

Transthoracic needle aspiration biopsy is reported to be of little diagnostic use.[8] Surgical excision is the recommended choice for diagnostic and therapeutic purpose. However, there is a potential complication of substantial blood loss. According to Cohen et al., subtotal resection is a therapeutic option for infiltrative cases, without increased risk of local recurrence, hemorrhagic morbidity, malignant transformation, or becoming symptomatic.[1] Other treatment modalities including radiotherapy and venovenous extracorporeal membrane oxygenation have been reported in critical cases.[59]

68Ga-DOTATATE PET/CT is an established method for the evaluation of NETs. It is used for SSTR imaging, which is overexpressed in various tumors, such as NETs (carcinoid, insulinoma, and pheochromocytoma), meningioma, pituitary adenoma, Merkel cell carcinoma, and medullary thyroid carcinoma. There are very few benign differentials for uptake of SSTR analogs. Low-grade uptake is known in reactive nodes, prostatitis, sarcoidosis, and other inflammatory conditions, as activated macrophages and lymphocytes express SSTRs on their surface.[10] There are few case reports demonstrating somatostatin receptor expression in vertebral, intraosseous, primary nodal hemangiomas, in which the exact mechanism of uptake is unclear.[1112131415] 68Ga-DOTATATE uptake in bone hemangiomas is well-known; however, its uptake in a mediastinal capillary hemangioma is worth knowing as it might change the clinician’s perspective.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Acknowledgement

We sincerely acknowledge Dr. Vimesh Rajput, Consultant, Department of Cardiovascular and Throacic Surgery for case referral and sharing the case details for us to publish the case and Dr. Sonal Bhandare, Consultant, Surgical Pathology for sharing the microscopy images of the specimen resected.
==== Refs
1 Cohen AJ Sbaschnig RJ Hochholzer L Lough FC Albus RA Mediastinal hemangiomas Ann Thorac Surg 1987 43 656 9 3592837
2 Davis JM Mark GJ Greene R Benign blood vascular tumors of the mediastinum. Report of four cases and review of the literature Radiology 1978 126 581 7 628723
3 Abe K Akata S Ohkubo Y Park J Kakizaki D Simatani H Venous hemangioma of the mediastinum Eur Radiol 2001 11 73 5 11194921
4 Yoshino N Okada D Ujiie H Akiyama H Nishimura Y Koizumi K Venous hemangioma of the posterior mediastinum Ann Thorac Cardiovasc Surg 2012 18 247 50 22790999
5 Kwok-Williams M Perez Z Squire R Glaser A Bew S Taylor R Radiotherapy for life-threatening mediastinal hemangioma with Kasabach-Merritt syndrome Pediatr Blood Cancer 2007 49 739 44 16453298
6 Cabral FC Trotman-Dickenson B Madan R Hypervascular mediastinal masses: Action points for radiologists Eur J Radiol 2015 84 489 98 25557510
7 McAdams HP Rosado-de-Christenson ML Moran CA Mediastinal hemangioma: Radiographic and CT features in 14 patients Radiology 1994 193 399 402 7972751
8 Schurawitzki H Stiglbauer R Klepetko W Eckersberger F CT and MRI in benign mediastinal haemangioma Clin Radiol 1991 43 91 4 2004520
9 Huang W Ye H Yang T Cheng Z Zhang J Miu Z Extracorporeal membrane oxygenation-combined surgery for hemoptysis caused by a mediastinal hemangioma Ann Thorac Surg 2021 111 e121 5 32652072
10 Hofman MS Lau WF Hicks RJ Somatostatin receptor imaging with 68Ga DOTATATE PET/CT: Clinical utility, normal patterns, pearls, and pitfalls in interpretation Radiographics 2015 35 500 16 25763733
11 Brogsitter C Hofmockel T Kotzerke J (68)Ga DOTATATE uptake in vertebral hemangioma Clin Nucl Med 2014 39 462 3 24152639
12 Vertenten B Goethals L De Geeter F (68)Ga DOTATATE uptake in hemangioma simulating metastasis on PET imaging: CT helps characterize bone hemangioma that could be wrongly interpreted as skeletal metastases on (68)Ga DOTATATE PET imaging J Belg Soc Radiol 2019 103 38 31276092
13 Saidi B Fallahi B Manafi-Farid R Fard-Esfahani A Eftekhari M 68Ga-DOTATATE uptake in an intraosseous hemangioma, as a potential cause of false-positive PET/CT finding, simulating tumoral involvement Clin Nucl Med 2022 47 e274 5 35025790
14 Sariyildiz Gumusgoz H Burak Z Karasah Erkek B Unusual 68 Ga-DOTATATE uptake in primary nodal hemangioma of axillary lymph node Clin Nucl Med 2022 47 809 10 35353744
15 Shah A Binkovitz L Layman AJ Bois MC Nguyen B Cardiac hemangioma mimicking a neuroendocrine tumor on (68)Ga Dotatate PET/CT J Card Surg 2022 37 2849 51 35502494
