A Rare Case of Intravascular Papillary Endothelial Hyperplasia (Masson’s Tumor) of Vocal Cord

Abstract

Background: Intravascular papillary endothelial hyperplasia (IPEH) also known as Masson’s tumour named after Pierre Masson is a benign lesion of vascular origin which is characterized by reactive proliferation of endothelial cells with papillary formation. It is an extremely rare entity which can present anywhere in the body but is particularly found in the extremities and head and neck regions most commonly the lips, oral mucosa, tongue, gingiva, or buccal mucosa and due to its close resemblance to Angiosarcoma, it becomes important to distinguish between these two entities to avoid unnecessary aggressive treatment. Case Report: Here, we describe a case of 23-year-old male who presented with change in voice since 8 months. Preoperatively, laryngoscopic examination showed right vocal cord polyp in the anterior one-third of the cord with hemorrhagic changes. He underwent micro-laryngeal surgery using suspension laryngoscope and the lesion was excised completely. Histopathological report was consistent with IPEH. Conclusion: Herein, we describe a rare benign case of IPEH arising from the vocal cord and we provide a brief review of relevant literature and a detailed report of this rare entity.

Introduction

IPEH also known as Masson’s tumor is an unusual benign lesion of vascular origin comprising 2% of the vascular tumors of the skin and subcutaneous tissues [1, 2]. It was first described by Pierre Masson in 1923 and has been given other names – Masson’s pseudo Angiosarcoma, Masson’s tumor or vegetant intravascular hemangioendothelioma.

This tumor typically exists in the lumen of the dilated vascular spaces or in pre-existing vascular lesions [3]. It most commonly occurs in the hands, extremities and head and neck region commonly affecting the skin and subcutaneous tissues, lip, oral mucosa, tongue, gingiva, or buccal mucosa [3]. Rarely, it can occur in the orbits, parotid glands, sinuses, nose etc. [2, 3]. To the best of our knowledge, only 2 cases of IPEH have been reported in the glottis region in English literature [1, 4].

Since IPEH has a close resemblance to Angiosarcoma, it becomes important to distinguish between these two entities. Histopathology and immunohistochemistry can help distinguishing between these two and will also avoid unnecessary treatment [3].

Masson’s Tumor requires a simple surgical excision and has an excellent prognosis. We present a 3rd reported case of Masson’s Tumor which presented as a mass of the vocal cord and which was diagnosed after complete surgical excision.

Case Report

A 23-year-old male presented to the department of ENT and head and neck surgery with complaints of change in voice for 8 months which was observed by his colleagues at work. He was a timber worker by occupation and occasionally had to raise his voice. He was a non-smoker and did not consume alcohol. He had no history of cough with expectoration, dysphagia, hemoptysis, or dyspnea.

Oral cavity and oropharyngeal examination were unremarkable. No enlarged lymph nodes were palpable. Laboratory blood tests were also unremarkable. Laryngoscopic examination showed right vocal cord polyp in the anterior one-third of the cord.

Patient underwent Micro-laryngeal surgery under general anesthesia after taking informed written consent. Using suspension laryngoscopy, the lesion on the anterior one third of the right vocal cord was identified as vocal cord polyp with hemorrhagic changes. Local infiltration of lignocaine with 1 in 100,000 concentration adrenaline was given sub-epithelially to reduce bleeding. With the help of micro-laryngeal scissors, the polyp was excised completely and sent for histopathological examination. Immunohistochemistry was not performed as the patient was not affordable for the same.

Patient received anti-reflux medications post-operatively and was discharged 2 days after strict instructions of voice rest for at least 2 weeks.

On histopathological examination, the section showed surface epithelium with Toto-bodies with anastomosing vascular channels and luminal thrombi and papillary endothelial hyperplasia with areas of hyalinization. In this case, immunohistochemistry was not done. The definitive diagnosis was IPEH. Post-operatively, video-laryngoscopic imaging showed that the mass was completely excised and patient was satisfied with the voice and is currently asymptomatic till date (Figs.. 1, 2, and 3).

Fig. 1.

Pre-operative laryngoscopic examination showing right vocal cord polyp from the anterior part of the cord

Fig. 2.

Slide showing anastomosing vascular channels with luminal thrombi and endothelial hyperplasia

Fig. 3.

[a] Slide showing numerous Toto bodies

Discussion

Masson’s Tumor can be divided into three types based on the involvement of the proliferating endothelial cells around a thrombus [5]:

Primary form (pure type- 56%) that arises in the dilated lumen of vascular spaces.

Secondary (mixed – 40%) type arises due to focal changes in pre-existing vascular lesions like hemangioma, pyogenic granuloma, etc.

Extravascular form (rarest form- 4%) which develops in association with organization of hematomas and this is difficult to differentiate from Angiosarcoma.

The patient in our case was not a professional voice user but had a history of voice abuse. The histopathological examination indicated sub-epithelial anastomosing vascular channels showing evidence of luminal thrombi and papillary endothelial hyperplasia. Hence, it can be considered as primary form originating from the true vocal cord. IPEH can affect between the ages of 9 months to 80 years [2]. Although, a slight female preponderance has been reported, both genders are equally affected [2].

The pathogenesis of IPEH is unknown but many mechanisms have been proposed [3]. One of which is an intravascular endothelial proliferation with papillary formation leading to necrosis and degeneration [6]. Other mechanisms include – exuberant endothelial proliferation with papillary formation arising from a thrombus; blood stasis and perivascular inflammation [6, 5]. Macrophages which are attracted by the thrombus may promote endothelial cell proliferation by releasing fibroblast growth factor resulting in increased proliferation [3]. There are some indications stating that trauma might be one of the causes of abnormal proliferation of endothelial cells surrounding a thrombus [3].

Histopathological examination is one of the important components to diagnose Masson’s Tumor. Clinical and radiological characteristics of IPEH are non-specific and can mimic various vascular neoplasms like Angiosarcoma, Kaposi sarcoma, hemangioma and lymphangioma [5, 6]. The histopathological features of IPEH closely resemble Angiosarcoma. Important histopathological findings that can help to differentiate between the 2 entities include (1) endothelial cell proliferation being confined within the vascular lumen in contrast to Angiosarcoma where it tends to invade surrounding tissues and has an infiltrative growth pattern. (2) A lack of necrosis and cellular pleomorphism or atypical mitoses (3) most of the papillary structure being associated with thrombi [3]. Additionally, immunohistochemistry can be used to facilitate the diagnosis even though histopathology is sufficient. IPEH is positive for CD31, CD34 and SMA (smooth muscle actin)0.5 In the present case, immunohistochemistry was not performed as the patient was not affordable for the same.

Since IPEH has an excellent prognosis, it becomes important to exclude malignant vascular neoplasms to avoid misdiagnosis and unnecessary treatment. The best treatment is complete surgical excision [3, 4]. In intracranial lesions or where complete excision is not feasible, adjuvant chemo/radiotherapy can be given to achieve lesion stabilization and short-term regression. No metastatic cases have been reported till date indicating that IPEH is strictly benign. The prognosis is good with exceptions of certain intracranial cases [4].

In our case, the patient was diagnosed with a vocal cord polyp/cyst with hemorrhagic changes pre-operatively. Post-operatively, the histopathological features were consistent with IPEH. Since the excision was complete, a good prognosis is expected.

Conclusion

IPEH is a rare benign entity which occurs mostly in head and neck region and it has the ability to mimic a variety of benign and malignant lesions in the orofacial region. Appropriate diagnosis of this entity will prevent incorrect diagnosis and unnecessary aggressive treatment. Complete surgical excision is the optimal treatment of choice and has an excellent prognosis. Reporting this entity in the glottic region is particularly uncommon, making it a valuable resource for avid readers who wish to gain a comprehensive understanding of it.

Declarations

Conflict of Interest

The authors declare that they have no conflict of interest.

Research Involving Human Participants and/or Animals

Yes, Human participants.

Informed Consent

Informed Written Consent was taken.