Adenoid Cystic Carcinoma

Abstract

Adenoid cystic carcinoma is a malignant tumor with a deceptively benign histologic appearance characterized by indolent, locally invasive growth with high propensity for local recurrence and distant metastasis. The tumor is composed of basaloid cells with small, angulated, and hyperchromatic nuclei and scant cytoplasm arranged into 3 prognostically significant patterns: cribriform, tubular, and solid. Some tumors undergo dedifferentiation into a high-grade form. Numerous studies have attempted to elucidate accurate histologic prognostic features but have often yielded conflicting results. Microarray analysis and gene expression profiling have provided new potential diagnostic and prognostic markers. However, tumor grade, stage, lymph node metastasis, invasion of major nerves, and margin status remain the most consistent predictors of prognosis. The combination of surgery and postoperative radiation therapy has improved locoregional control of the disease. Despite this achievement, late local recurrence and distant metastasis rates remain high and may occur decades after initial diagnosis.

Clinicopathological Correlation of Adenoid Cystic Carcinoma: A Notorious Masquerader and Clinical Paradox

“…Although ACC was first described in 1853, the term was denominated by Spies later in 1930. [5] The usual peak incidence of ACC is between 50 and 60 years of age with a slight female preponderance, [6] and our results were in concordance with published literature. ACC comprises 10% of all salivary gland tumors and most commonly affects the submandibular gland followed by parotid gland.…”

The Immune Landscape of Chinese Head and Neck Adenoid Cystic Carcinoma and Clinical Implication

“…Three growth patterns of ACC have been described: cribriform, tubular, and solid. The cribriform and tubular growth patterns are less aggressive (4). Tumors that exhibit a solid pattern or have solid components are more likely to spread and have a worse prognosis (7)(8)(9).…”

“…Adenoid cystic carcinoma (ACC) is a rare malignancy predominantly arising from salivary glands, accounting for about 1% of all head and neck malignant tumors (1)(2)(3). ACC is characterized by indolent but relentless growing, perineural invasion and perineural spread, high propensity for local recurrence after initial treatment, and common distant metastasis (4). Although postoperative radiotherapy has been shown to increase the local control rate by 89-95% within 5 years (5,6), the disease-free survival rates decline dramatically at 10 and 15 years (6)(7)(8)(9)(10)(11)(12)(13).…”

Tracheobronchial Adenoid Cystic Carcinoma: 50-Year Experience at the National Cancer Center, China

“…1,2 Adenoid cystic carcinoma, first described in the 1850s, is a low-grade malignant tumor and accounts for 22% of all malignant salivary gland tumors. [3][4][5] Tracheobronchial adenoid cystic carcinoma (TACC) originates from the submucosal glands of the tracheobronchial tree. The incidence of tracheal tumors is uncommon, accounting for only 0.09% to 0.20% of all lung cancers, and TACC accounts for 10% of tracheal tumors.…”