A case of cutaneous bronchogenic cyst in the scapular area

Introduction

Bronchogenic cysts originate from the primitive tracheobronchial tree and are primarily located in the thorax [1, 2]. Cutaneous bronchogenic cysts are not common lesions which are often diagnosed histopathologically [3-11]. Especially, there are rare reports regarding cutaneous bronchogenic cyst in the scapular location [1-6]. Herein, we report a 4-year-old boy who presented with bronchogenic cyst and relapsing infection in the right scapular region.

Case report

A 4-year-old boy was noted to have a lesion in his right scapular region after 10 months old. The mass caused repeating infection, and required incision and pus discharge several times. The legion was resected in Tohoku University Hospital, and histopathological analysis was performed. The mass was fragile and appeared grey to brown. The cavity was filled with pus and encircled by a thick fibrous wall.

Histopathological findings

Microscopically, a large cavity was detected in the centre of the specimen. The cyst was lined with respiratory epithelium and partially encircled by smooth muscle bundles (Fig. 1A) or squamous epithelium with sebaceous glands (Fig. 1B). Foci of haemorrhage, inflammation and fibrosis were also detected in this cavity wall (Fig. 1C). The tumour was histopathologically diagnosed as a cutaneous bronchogenic cyst.

Discussion

Cutaneous bronchogenic cysts are rare lesions that are mostly seen in children, and the most common location of these lesions are the suprasternal notch, presternal area, neck and scapula [3, 7].

It is postulated that bronchogenic cysts are originally derived from outside of the thorax after sternal closure, and migrate to the cutaneous region [3]. On the other hand, it is also suggested that the cyst simply pinches off from the developing tracheal bud during closure of the mesenchymal plates [3, 8, 9]. However, the exact mechanism still remains unclear.

The pathological diagnosis is performed by demonstrating one or more tracheobronchial structures in the cyst wall [3]. In most cases, hyaline cartilage, smooth muscle cells, elastic fibres, fibrous tissues, neural cells and seromucous glands are microscopically detectable [3, 8, 10]. The surface epithelium is usually ciliated pseudostratified columnar or cuboidal cells; however, these structures may be changed in conditions of chronic infections and fibrosis [3, 10]. Stratified squamous epithelium can be seen in 2% of cutaneous bronchogenic cysts [3, 7]. In addition, some rare cases may show sebaceous glands [6, 11]. Based on these findings, our case was histopathologically diagnosed as a cutaneous bronchogenic cyst in the scapular area.

In conclusion, the possibility of bronchogenic cysts should be kept in mind while dealing with superficial scapular skin lesions in children.

References

 1. Kundal AK, Zargar NU, Krishna A. Scapular bronchogenic cyst. J Indian Assoc Pediatr Surg 2008; 13: 147-148.  

2. Bagwell CE, Schiffman RJ. Subcutaneous bronchogenic cysts. J Pediatr Surg 1988; 23: 993-995.  

3. Ozel SK, Kazez A, Koseogullari AA, et al. Scapular bronchogenic cysts in children: case report and review of the literature. Pediatr Surg Int 2005; 21: 843-845.  

4. Pul N, Pul M. Bronchogenic cyst of the scapular area in an infant: case report and review of the literature. J Am Acad Dermatol 1994; 31: 120-122.  

5. Schouten van der Velden AP, Severijnen RS, Wobbes T. A bronchogenic cyst under the scapula with a fistula on the back. Pediatr Surg Int 2006; 22: 857-860.  

6. Tanita M, Kikuchi-Numagami K, Ogoshi K, et al. Malignant melanoma arising from cutaneous bronchogenic cyst of the scapular area. J Am Acad Dermatol 2002; 46: S19-21.  

7. Zvulunov A, Amichai B, Grunwald MH, et al. Cutaneous bronchogenic cyst: delineation of a poorly recognized lesion. Pediatr Dermatol 1998; 15: 277-281.  

8. Magnussen JR, Thompson JN, Dickinson JT. Presternal bronchogenic cysts. Arch Otolaryngol 1977; 103: 52-54  

9. Miller OF, Tyler W. Cutaneous bronchogenic cyst with papilloma and sinus presentation. J Am Acad Dermatol 1984; 11: 367-371.

10. Fraga S, Helwig EB, Rosen SH. Bronchogenic cyst in the skin and subcutaneous tissue. Am J Clin Pathol 1971; 56: 230-238.

11. van der Putte SC, Toonstra J. Cutaneous 'bronchogenic' cyst. J Cutan Pathol 1985; 12: 404-409.

Address for correspondence

Yasuhiro Nakamura , MD

Department of Pathology

Tohoku University School of Medicine

2-1 Seiryo-machi, Aoba-ku, Sendai

980-8575 Japan

tel. +81-22-717-8050

fax +81-22-717-8051

e-mail: yasu-naka@patholo2.med.tohoku.ac.jp