Should we treat lung metastases from adenoid cystic carcinoma of the head and neck in asymptomatic patients?(ORIGINAL ARTICLE)(Report)

Abstract

Adenoid cystic carcinoma is a rare malignant tumor that is well known for its deceptively encouraging 5-year survival rate and its dismal survival rate at longer intervals. Controversy exists as to the benefit of regularly following asymptomatic patients to look for distant metastases because even if one is found, the options for further management are limited. When a metastasis is limited to the lung in an asymptomatic patient with no locoregional recurrence, metastasectomy might provide some long-term benefit, although we cannot know for certain. We encountered such a case, and we opted for surgical resection rather than a conservative approach. There is a need for multicenter trials so that the management of such patients, be it active or conservative, can be evidence-based.

Introduction

Adenoid cystic carcinoma (ACC) is an aggressive epithelial tumor that is well known for its indolent course and ultimately poor prognosis. When it occurs in the head and neck, ACC most commonly arises in the minor salivary glands. ACC accounts for 10% of all salivary neoplasms and less than 1% of all tumors of the larynx. (1,2) Laryngeal ACC usually arises from the subglottic area near the tracheal junction, and it tends to spread circumferentially before invading intrinsic laryngeal muscles and cartilage. The thyroid becomes involved via anterior spread through the cricothyroid membrane, and tracheal invasion occurs via caudal extension of the tumor. (3)

Hematogenous spread is common in both the early and late courses of ACC. The lung is the most common site of metastasis, as pulmonary metastases have been reported in more than 40% of patients with ACC of the head and neck. (4,5) Once ACC of the head and neck becomes symptomatic or when a visceral extrathoracic metastasis appears, the course of the disease becomes fairly predictable, and patients seldom survive for more than 2 years. However, this does not appear to be the case in asymptomatic patients when the only detectable site of spread is the lung; these patients generally experience a much longer survival. Therefore, the presence of a lung metastasis in an asymptomatic patient with no local recurrence poses a dilemma for both the physician and patient regarding the initiation of treatment, if any.

The literature concerning the appropriate management of metastatic laryngeal ACC in an asymptomatic patient with no local recurrence is limited because of the scarcity of reported cases. In this article, we discuss the problems posed by such a case at our institution, and we review the evidence for and against the use of various interventions.

Case report

A 29-year-old woman first presented to the Royal National Throat, Nose and Ear Hospital in London in 1988 with an 8-month history of hoarseness and mild shortness of breath. She was found to have a 6-cm tumor that had arisen in the subglottis, extended down the trachea, and infiltrated the cricoid cartilage, the tracheal muscle, the surrounding soft tissue, and the thyroid. She was treated with a total wide-field laryngectomy, total thyroidectomy, and manubrial resection with postoperative radio therapy (4,800 Gy in…