Adenoid cystic carcinoma. An indolent but aggressive tumour. Part A: from aetiopathogenesis to diagnosis

Abstract

Adenoid cystic carcinoma (ACC) is a relatively rare tumour of the minor and major salivary glands. It is uncommon in the parotid gland while it is much more frequent in the submandibular gland and in minor salivary and mucinous glands (oral cavity, oropharynx, and paranasal sinuses). ACC may also arise in secretory glands located in other tissues, such as in the tracheobronchial tree, oesophagus, breast, lungs, prostate, uterine cervix, lachrymal and Bartholin's glands, and skin. The natural history of ACC is characterised by an indolent growth rate, a relatively low probability of regional lymph node metastases and a high likelihood of haematogenous dissemination. ACC has been traditionally subdivided into three histological groups (cribriform, tubular, and solid) based on solid components of the tumour. Some studies have shown that tumours with a solid growth component have a rapid fatal course, compared to tumours without a solid growth component, but other studies have failed to correlate growth patterns with clinical course. The purpose of this review is to analyse the very large number of studies (sometimes contradictory) on ACC. In this first part, the aetiology, epidemiology, histopathology, clinical behaviour and diagnostic workup are examined. KEY WORDS: adenoid cystic carcinoma, salivary gland tumours, head and neck cancer, prognostic factors RIASSUNTO Il carcinoma adenoide cistico (ACC) è un tumore relativamente raro ad origine dalle ghiandole salivari minori e maggiori. È poco frequente nella parotide mentre lo è molto di più nella ghiandola sottomandibolare, nelle ghiandole salivari minori e in quelle mucinose del cavo orale, orofaringe e seni paranasali. Esso può anche insorgere nelle ghiandole secretrici localizzate in altri tessuti come l'albero tracheo-bronchiale, l'esofago, la mammella, il polmone, la prostata, la cervice uterina, la cute, le ghiandole lacrimali e quelle del Bartolini. La sua storia naturale è caratterizzata da una lenta crescita, da rare metastasi linfonodali e da frequenti metastasi a distanza. Dal punto di vista istologico esso è stato tradizionalmente suddiviso in tre forme (cribriforme, tubulare e solido). Alcuni studi hanno dimostrato che i tumori con una prevalente componente solida hanno una prognosi peggiore rispetto a quelli con prevalente componente cribriforme o tubulare ma altri studi hanno contestato questa affermazione. Il proposito di questa review è quello di analizzare il grande numero di pubblicazioni (talvolta contraddittorie) sul carcinoma adenoide cistico. In questa prima parte saranno discusse l 'eziologia, l'epidemiologia, l'istopatologia, la presentazione clinica e l'iter diagnostico.

Adenoid cystic carcinoma of the sublingual gland developing lung metastasis 20 years after primary treatment

“…[ 1 , 6 ] The common clinical symptoms are a slowly growing mass, mild pain, and paresthesia. [ 1 , 7 ] The duration of these symptoms ranges from months to several years. [ 7 ] The most predominant site of distant metastasis is the lung, followed by the bone and liver.…”

“…[ 1 , 7 ] The duration of these symptoms ranges from months to several years. [ 7 ] The most predominant site of distant metastasis is the lung, followed by the bone and liver. [ 1 ] The survival rates at 5-, 10-, 20-, and 25-years are 68%, 52–65%, 27–28%, and 20%, respectively.…”

Unilateral multifocal pleomorphic adenoma of parotid gland with panlobular involvement—A diagnostic dilemma

“…Adenoid cystic carcinoma is an infiltrative malignant lesion with a tendency for perineural invasion which also demonstrates myoepithelial differentiation. 4 Ultrasound can be used to identify the facial nerve within the parotid gland. The extra-cranial part of the facial nerve was scanned on the side of the parotid lesion along its longitudinal axis inside the parotid gland using a 5 MHz linear array transducer.…”

“…However, the differentiating clinical sign is eversion of the ear lobe which is caused by pleomorphic adenoma, while Warthin's tumor does not. Adenoid cystic carcinoma is an infiltrative malignant lesion with a tendency for perineural invasion which also demonstrates myoepithelial differentiation 4 …”

Male Adenoid Cystic Carcinoma of the Breast

“…Adenoid cystic carcinoma (ACC) was first discovered by Robin and Laboulbene in 1853 and described as “tumeur heteradenique” [ 1 ]. Then ACC was first used in breast oncology by Geschikter in 1945 [ 2 ].…”