In the discussion of malignancies, a clear word about its masquerading conditions is essential. In this write-up, I present three conditions that mimic malignancies in the ear, nose and throat.
Malignant otitis externa
Malignant otitis externa is a life-threatening condition that presents and spreads aggressively like a malignancy. It is an infection of the external auditory canal commonly caused by Pseudomonas aeruginosa. The name Malignant otitis externa is thus a misnomer even though due to the high incidence of mortality it was earlier termed so. The infection often spreads to the adjacent skull base. In recent times various terms are used for this condition including “Necrotising otitis externa”, “skull base osteomyelitis” and “Osteitis of the base of skull”.
Most patients affected by this condition are elderly diabetics. Patients with immunosuppressive clinical states are also prone to this infection. The affected person usually presents with excruciating ear pain, and purulent and blood stained ear discharge with varying degrees of hearing loss. On examination exuberant granulation in the floor of the external auditory canal is often found, most commonly at the bony cartilaginous junction. The pus can be sent for culture sensitivity and a small bit of tissue for HPE may also be removed.
The disease usually starts as a simple infection of the external ear skin but can spread through the bony-cartilaginous junction or directly through the bone to involve the mastoid, TM joint, infratemporal and masticatory spaces and the base of the skull. When it involves the stylomastoid and jugular foramina, the patient will have Facial nerve (commonly involved) and Lower cranial nerve palsies (IX,X,XI).
Radiological imaging studies (CT/MRI) show the extent of involvement of bone and soft tissue (intra/extracranial structures). Contrast-enhanced MRI is the gold standard to study soft tissue involvement. The Tc99 scan is useful for the initial evaluation of the infection while the Ga67 scan is a useful tool for monitoring the treatment and studying the resolution.
Treatment involves strict glycemic control and management of the immunosuppressive state. Meticulous aural toileting and removal of necrotic debris and sequestra have to be done. Antibiotic ear drops and antibiotic-impregnated ear wicks can be used. An antipseudomonal agent is commonly used initially and this can later be changed based on the culture sensitivity report. Systemic anti-microbial treatment (oral or parenteral) is initiated, usually fluoroquinolones. In resistant infections, we can use antipseudomonal penicillin with or without an aminoglycoside. Antibiotics are given for a period of 4-6 weeks and after which the patient is re-evaluated. Surgical debridement of the bony sequestrum may be reserved for patients who do not respond to medical management.
Tuberculous laryngitis
One form of extra-pulmonary tuberculosis is Laryngeal tuberculosis. It is not an uncommon presentation.In the pre-antibiotic period, laryngeal TB was quite common. The clinical presentation of TB larynx can be confused with laryngeal carcinoma.
Patients usually present with complaints of painful swallowing, chronic cough and voice change with or without systemic symptoms. The disease is highly contagious at this phase, with high rates of sputum positivity. Most patients have co-existing active pulmonary TB. Many of them are malnourished and may have some kind of immunodeficient condition. Internally, the laryngeal lesions usually are multiple, pale, sessile polypoidal, or granulomatous with a circumferential involvement. In some patients there can be ulceration and also perichondritis. The most common site involved is the true vocal cord and recently many patients presenting with epiglottic involvement have been observed.
Computed tomography of the neck shows diffuse thickening of the vocal cords on both sides. Involvement of the epiglottis and paralaryngeal spaces can also be picked up. In some patients with chronic tuberculous laryngitis, there may be a localised mass on the vocal cord. The laryngeal framework is usually preserved without cartilage destruction and the disease usually does not spread to adjacent structures. Cervical lymphadenopathy with peripheral rim enhancement and central hypodensity can also be present.
Antituberculous medications should be started at the earliest to relieve patients of their symptoms. If left untreated the cricoarytenoid joint may get fixed and in rare cases, this may lead to laryngeal stenosis both of which can have a permanent bearing on the patient’s voice and breathing. Hence early identification and initiation of treatment are very important.
Inflammatory myofibroblastic tumour of the nose
Inflammatory myofibroblastic tumor is known by several names. It was earlier called Inflammatory pseudotumor and Plasma cell granuloma. This condition mimics a malignancy not only clinically but also radiologically. It is a slow-growing inflammatory expanding lesion. It is commonly reported in the lung. The other frequent sites are mesentery, omentum and orbit. It is uncommon in the larynx and nasal cavity. The clinical picture when the nasal cavity is primarily involved in this condition is as follows.
Patients present with a history of progressive nasal block and loss of smell. They can have varying degrees of facial pressure/pain, eye pain, swelling in the face and eyes, and dental pain, depending on the extent of involvement. In rare cases, patients have a history of bleeding from the nose. On examination, it appears as a lobulated reddish-grey mass in the nasal cavity with a firm texture.
Radiologically the lesion is nonspecific and has variable features both on CT and MRI. In lesions affecting the nose and paranasal sinuses, there can be the destruction of adjacent bony wall and also an extension into the orbits arousing suspicion of malignancy and even fungal infections.
Tissue samples sent for HPE show proliferation of spindle cells -fibroblasts or myofibroblasts, along with an infiltration of inflammatory cells. Inflammatory infiltrate is composed of plasma cells, lymphocytes, neutrophils and eosinophils. Immunohistochemistry show diffuse positivity for Vimentin. Smooth muscle actin, desmin, cytokeratin and ALK can also be positive.
Treatment often requires surgical excision and sometimes RT. The approach to nasal lesions can be endoscopic or open depending on the extent of the disease. Patients are counselled for a regular follow-up.
To differentiate malignancies from their mimickers is life changing for the patient. It saves a lot of expenditure of emotions, effort and funds.
Dr. Preethi
Consultant ENT Surgeon
Kauvery Hospital Chennai