Kawamoto Nobutaka, Okita Riki, Hayashi Masataro, Osoreda Hisayuki, Inokawa Hidetoshi, Murakami Tomoyuki
Department of Thoracic Surgery, National Hospital Organization Yamaguchi Ube Medical Center, 685 Higashikiwa, Ube, Yamaguchi 755-0241, Japan.
Department of Thoracic Surgery, National Hospital Organization Yamaguchi Ube Medical Center, 685 Higashikiwa, Ube, Yamaguchi 755-0241, Japan.
Int J Surg Case Rep. 2022 Apr;93:106956. doi: 10.1016/j.ijscr.2022.106956. Epub 2022 Mar 15.
Solitary endotracheal papilloma is a rare benign lung tumor. It is classified into the following three histological subtypes: squamous cell papilloma (SP), glandular papilloma (GP), and mixed squamous cell and glandular papilloma (MSGP). MSGP is the rarest among them. Herein, we describe a case of a large MSGP.
A 59-year-old woman underwent computed tomography for the examination of cough, and an 8.2-cm-sized lung mass was noted in the left lingual segment. Bronchoscopy revealed that the left B lumen was completely occluded by a tumor. Transbronchial lung biopsy suggested GP; thereafter, a left upper lobectomy was performed. Macroscopic findings showed that the dilated B lumen was filled with cauliflower-like tumors. Histopathological findings showed that the majority of the tumors had pseudostratified columnar epithelium, while some had stratified squamous epithelium. The patient was diagnosed with MSGP. Although koilocytosis-like changes, such as perinuclear halo and nuclear deformation, were observed in some portions of the squamous epithelium, immunohistochemical staining was negative for human papillomavirus (HPV).
HPV infection is reportedly associated with SP but not with GP and MSGP. Therefore, MSGP is considered to be caused by squamous metaplasia of a part of GP; this hypothesis is consistent with the present case. However, only one case of MSGP with HPV infection was recently reported, and the etiology and histological features of MSGP remain unclear.
There are few reported cases of MSGP, and further case reports are needed to clarify its pathogenesis.
孤立性气管内乳头状瘤是一种罕见的肺部良性肿瘤。它可分为以下三种组织学亚型：鳞状细胞乳头状瘤（SP）、腺性乳头状瘤（GP）和混合性鳞状细胞和腺性乳头状瘤（MSGP）。其中MSGP最为罕见。在此，我们描述一例巨大MSGP病例。
一名59岁女性因咳嗽接受计算机断层扫描检查，发现左舌段有一个8.2厘米大小的肺部肿块。支气管镜检查显示左B管腔被肿瘤完全阻塞。经支气管肺活检提示为GP；此后，进行了左上肺叶切除术。宏观检查发现扩张的B管腔内充满了菜花状肿瘤。组织病理学检查发现，大部分肿瘤具有假复层柱状上皮，而部分具有复层鳞状上皮。该患者被诊断为MSGP。尽管在鳞状上皮的某些部分观察到了核周晕和核变形等凹空细胞样改变，但人乳头瘤病毒（HPV）免疫组化染色为阴性。
据报道，HPV感染与SP有关，但与GP和MSGP无关。因此，MSGP被认为是由部分GP的鳞状化生引起的；这一假说与本病例相符。然而，最近仅报道了一例HPV感染的MSGP病例，MSGP的病因和组织学特征仍不清楚。
MSGP的报道病例较少，需要进一步的病例报告来阐明其发病机制。
