Malignant melanoma of the nasal cavity (a case report).
A case of malignant melanoma of the nasal cavity is reported. The rarity of its occurrence warrants its mention.
Melanomas of the nose and paranasal sinuses are rare, contributing to only around 1% of all malignant melanomas. Due to lack of any characteristic clinical features, the diagnosis is often based on histopathological examination. The mainstay of treatment remains surgical excision.
A 75-year-old female presented with a swelling in the left nostril, causing obstruction to breathing, and increasing gradually since past 7-8 months. Complaints of headache were present. Epistaxis or rhinorrhoea was absent. She gave a history of tobacco chewing, occasional use of snuff, and long periods of exposure to sunlight, (being a farmer's wife.)
The swelling in the left nostril was dark blue, shiny, 1 cm in diameter, firm, with its origin apparently superiorly, and it was placed anterior to the inferior turbinate, almost occludim, the left anterior nare. Clinically no other findings were seen. Her haemogram and blood chemistry were within normal limits. An X-ray of the paranasal sinus showed no significant abnormality except a soft tissue mass in the left nostril.
An excision was done under local anaesthesia. The tumour was soft, friable, without much vascularity, and the origin was in the superior part of the vestibule.
On microscopy, the section showed a tumour composed of epitheloid and spindle cells arranged in lobules and small bundles. The nuclei were pleomorphic, hyperchromatic and contained prominent nucleoli. Cytoplasm showed abundant melanin pigment, scattered mitoses and tumour giant cells. Diagnosis of malignant nielanoma of infiltrating type was confirmed. (See [Figure - 1] )
The patient subsequently underwent a lateral rhinotomy and excision of the remaining area of tumour origin.
Malignant melanoma of the nose was first described by Lucke in 1869 (quoted by Cove). Its incidence in the nose and paranasal sinuses ranges between 0.5% and 1%,.
There is no predilection for either sex; the commonest age group affected is 5th or 6th decade. It generally does not present dramatically but may cause epistaxis and obstruction. There is no apparent correlation with chronic irritation, infection or allergy.
It is primarily a tumour of the nasal cavity arising from the nasal septum, lateral wall, inferior turbinates and rarely the floor and roof of the nose. Its presence in the paranasal sinuses is due to extension. One has to differentiate malignant melanoma clinically from polypi and other tumours.
On light microscopy sheets of closely arranged sphenoidal cells or spindle cells and multinucleated giant cells are seen. Pigmentation is variable. An amelanotic melanoma has to be differentiated from anaplastic carcinoma.
Regarding the site of origin, early concept that it is the mucocutaneous Junction is not substantiated. It is accepted that malignant melanomas of skin commonly arise from preexisting pigmented lesions-either junctional naevi or pre-cancerous melanosis of Dubreiutn.
Examination of nasal mucosa in malignant melanomas reveals similar junctional activity and melanin pigment may be found in the nasal cavity with or without junctional activity.
Thus a pre-existing dormant, nonfuncticonal variant of the melanocyte in normal nasal mucosa may get activated under certain conditions to neoplasia and junctional activity.
The site or size of the tumour gives no indication of the prognosis, but if secondaries are already present the prognosis is poor. Systemic spread occurs in 25%, cases and regional lymmph node metastases in 36%.
The mainstay of the treatment is wide surgical excision; chemotherapy and radiotherapy being not very effective. Recurrence is frequent upto 40%. The regression or non-recurrence of tumour depends upon the patient's immunological system. Serum of patient with malignant melanoma is shown to have antibodies, which are cytotoxic to such tumour cells in tissue culture. However, vaccination of patients with their own cells did not influence tumor regression. Varying results have been claimed by workers boosting the patient's immune system and the key to treating such tumours may well lie in this bodily defence system.