Home Translating Report News Physicians Diseases Body Sites Lab tests Search
Home Diseases and Health Information


This is the most common malignant tumor of the submandibular and minor salivary glands and comprises 4% of all salivary gland tumors. In the older literature, it is sometimes referred to as cylindroma. These tumors occur with a median age of 43 years. They commonly present as a slowly growing tumor with severe pain and occasionally with facial nerve paralysis as the tumor infiltrates into this nerve. These tumors have a history of relentless recurrence and becoming progressively more aggressive.


Disease Associations  
Laboratory/Radiologic/Other Diagnostic Testing  
Gross Appearance and Clinical Variants  
Histopathological Features and Variants  
Special Stains/
Electron Microscopy
Differential Diagnosis  
Commonly Used Terms  
Internet Links  

SYNONYMS Cylindroma
Adenocystic carcinoma
INCIDENCE 5th most common malignant epithelial tumor of the salivary gland
7.5% of all epithelial malignancies
4% of all benign and malignant salivary gland tumors
Peak incidence in 4-6th decades


Chromosomal abnormalities Some cases of anomalies withing 6q and 9p

Perineural invasion in adenoid cystic carcinoma: Its causation/promotion by brain-derived neurotrophic factor.

Kowalski PJ, Paulino AF.

University of Michigan Hospitals, Ann Arbor, MI.

Hum Pathol 2002 Sep;33(9):933-6 Abstract quote

Adenoid cystic carcinoma (ACC) is a common salivary gland neoplasm with a lengthy clinical course and often late local recurrences after surgical resection. This is accounted for histologically by its infiltrative capacity and distinct propensity for perineural invasion. The expression of biological markers may help explain the clinicopathologic course in ACCs. Brain-derived neurotrophic factor (BDNF) is a growth factor known to be involved in neurogenesis.

The aim of this study is to elucidate the expression of BDNF in ACCs, which is currently unknown. Twenty-nine cases of primary ACCs of the head and neck were immunostained to analyze BDNF protein expression. Staining intensity was described as focal or diffuse and graded on a 3-tiered scale. The study group comprised 20 adult females (age 30 to 78) and 9 adult males (age 22 to 70). Sites of involvement included the parotid gland (6 cases), nasopharynx (5), maxilla (4), palate (3), trachea (3), submandibular gland (2), buccal mucosa (2), mandible (1), tongue (1), lacrimal gland (1), and temporal region (1). All tumors exhibited diffuse cytoplasmic staining; 11 cases were classified as 1+ intensity, 12 cases as 2+, and six cases as 3+.

Based on the results presented here, BDNF is unformly expressed by ACC and may play a causative role in its predilection for perineural invasion. ACCs may display neurogenesis with high levels of BDNF expression in some tumors. Further studies are warranted to gain better understanding of this possible relationship.

Promoter methylation and protein expression of the E-cadherin gene in the clinicopathologic assessment of adenoid cystic carcinoma.

Maruya S, Kurotaki H, Wada R, Saku T, Shinkawa H, Yagihashi S.

[1] 1Department of Pathology [2] 2Department of Otorhinolaryngology, Hirosaki University School of Medicine, Hirosaki, Japan.
Mod Pathol. 2004 Jun;17(6):637-45. Abstract quote  

Adenoid cystic carcinoma, a relatively uncommon tumor of salivary glands, is characterized by a prolonged clinical course and a fatal outcome. The molecular events underlying their progression are unknown.

In this study, we examined the methylation status of E-cadherin gene and its protein expression in 23 cases of adenoid cystic carcinoma and correlated the results with the clinicopathologic factors to determine its role in these tumors. We also analyzed the effect of 5-azacytidine on the re-expression in a methylated cell line of adenoid cystic carcinoma for this gene. In our study, E-cadherin immunoreactivity, although heterogeneous, showed a progressive reduction with high histological grade and in metastatic and recurrent lesions. Promoter methylation was detected in 16 of 23 cases (70%), but there was no correlation with the histological grade or patient prognosis. Microdissection of immuno-negative cells in heterogeneous tumors showed positive methlyation. In the cell line from salivary adenoid cystic carcinoma with methylated E-cadherin, 5-azacytidine restored the E-cadherin expression.

Our results indicate that: (1) E-cadherin gene promoter is frequently methylated in adenoid cystic carcinoma, leading to reduced E-cadherin expression, (2) variable E-cadherin expression might result from the intratumoral heterogeneity, and (3) increased extent of methylated areas may be associated with progression and advancement of the disease.
Mutations in components of the Wnt signaling pathway in adenoid cystic carcinoma.

Daa T, Kashima K, Kaku N, Suzuki M, Yokoyama S.

1Department of Pathology, Faculty of Medicine, Oita University, Oita, Japan.
Mod Pathol. 2004 Dec;17(12):1475-82. Abstract quote

The Wnt signaling pathway is essential for normal development and organogenesis. However, inappropriate activation of Wnt signaling, which results in the nuclear translocation of beta-catenin, is associated with the development of various types of neoplasm.

In this study, we investigated possible mutations in the genes for components of this pathway, namely, CTNNB1 (the gene for beta-catenin), AXIN1, and APC, in adenoid cystic carcinoma, by PCR, analysis of single-strand conformational polymorphism, and sequencing. Among a total of 20 cases of adenoid cystic carcinoma, seven cases (35%) were associated with mutations in one or more of these three components. A mutation in CTNNB1 was detected in one case. Five cases, including the case with a mutation in CTNNB1, were associated with missense mutations in AXIN1. An aberration in the mutation cluster region of APC was detected in two cases. Mutations trended to be detected more frequently in adenoid cystic carcinoma with solid growth pattern than that with tubular and cribriform growth pattern.

In the cases in which we detected mutations, it is possible that the presence of the abnormal products of the mutated genes resulted in the inappropriate activation of the Wnt signaling pathway to tumorigenesis and the growth of adenoid cystic carcinoma.


General Firm gray white tumors which appear well circumscribed

Ceruminous Gland Adenoid Cystic Carcinoma With Contralateral Metastasis to the Brain

Phillip A. Conlin, MD, Jose Luis Mira, MD, Suzanne C. Graham, MD, Kim Sutker Kaye, MD, and Joehassin Cordero, MD

From the Department of Pathology and Laboratory Medicine, Texas Tech University Health Sciences Center, Lubbock, Tex (Drs Conlin, Mira, and Kaye); and the Department of Surgery, Division of Otolaryngology–Head & Neck Surgery, Texas Tech University Medical Center, Lubbock, Tex (Dr Cordero).

Arch Pathol Lab Med 2002;Vol. 126, No. 1, pp. 87–89. Abstract quote

We present the case of a 38-year-old man with an adenoid cystic carcinoma originating from the ceruminous glands of the external ear canal.

The patient subsequently presented with a contralateral brain mass that was also diagnosed as adenoid cystic carcinoma. To our knowledge, contralateral metastasis to the brain of a patient with an adenoid cystic carcinoma of the ceruminous glands has not been reported previously.

This rare neoplasm should be considered in the differential diagnosis of poorly differentiated carcinomas metastatic to the central nervous system in patients with occult malignant neoplasms.


General Hallmark of the tumor is peripheral nerve invasion
This is the classic histology of nests of cells with neatly punched out spaces, resembling a cookie-cutter
Cyst-like spaces are not true ductal or glandular lumina but are in continuity with the supporting connective tissue stroma
Tumor cells arranged in small nests separated from one another
True duct lumens surrounded by differentiated ductal cells are prominent
Islands of tumor cells in hyalinized stroma
Variably sized rounded or lobulated aggregates of tumor cells with few cyst like spaces
Mitotic figures may be abundant numbering up to 5 or more/10 hpf

Dedifferentiated adenoid cystic carcinoma: a clinicopathologic study of 6 cases.

Nagao T, Gaffey TA, Serizawa H, Sugano I, Ishida Y, Yamazaki K, Tokashiki R, Yoshida T, Minato H, Kay PA, Lewis JE.

Division of Anatomic Pathology, Mayo Clinic, Rochester, Minnesota 55905, USA.

Mod Pathol. 2003 Dec;16(12):1265-72 Abstract quote.  

Dedifferentiated adenoid cystic carcinomas are a recently defined, rare variant of adenoid cystic carcinomas characterized histologically by two components: conventional low-grade adenoid cystic carcinoma and high-grade "dedifferentiated" carcinoma.

We examined six cases and analyzed their clinicopathologic profiles, including immunohistochemical features and p53 gene alterations. The 6 patients (3 men and 3 women) had a mean age of 46.8 years (range, 34-70 y). The mean size of the tumors was 3.5 cm (range, 1.7-6 cm). The submandibular gland, maxillary sinus, and nasal cavity were involved in 2 cases each.

Postoperatively, 5 patients had local recurrence and 5 developed metastatic disease. Five patients died of disease at a mean of 33.7 months after diagnosis (range, 6-69 mo), and one other was alive with disease at 60 months. Histologically, the conventional low-grade adenoid cystic carcinoma component of the tumors consisted of a mixture of cribriform and tubular patterns with scant solid areas. The high-grade dedifferentiated carcinoma component was either a poorly differentiated adenocarcinoma (4 cases) or undifferentiated carcinoma (2 cases).

Three tumors were studied immunohistochemically. Myoepithelial markers were expressed in low-grade adenoid cystic carcinoma but not in the dedifferentiated component. In 2 cases, diffusely positive p53 immunoreactivity together with HER-2/neu overexpression was restricted to the dedifferentiated component. Loss of pRb expression was demonstrated only in the dedifferentiated component of the 1 other case. The Ki-67-labeling index was higher in the dedifferentiated component than in the low-grade adenoid cystic carcinoma component. Furthermore, molecular analysis of 2 cases demonstrated the loss of heterozygosity at p53 microsatellite loci, accompanied by p53 gene point mutation, only in the dedifferentiated carcinoma component of 1 case, which was positive for p53 immunostaining. These results indicate that dedifferentiated adenoid cystic carcinoma is a highly aggressive tumor.

Because of frequent recurrence and metastasis, the clinical course is short, similar to that of adenoid cystic carcinomas with a predominant solid growth pattern. Limited evidence suggests that p53 abnormalities in combination with HER-2/neu overexpression or loss of pRb expression may have a role in dedifferentiation of adenoid cystic carcinoma.

Dedifferentiation of adenoid cystic carcinoma: Report of a case implicating p53 gene mutation

Yuk-ping Chau, MBBS
Tadashi Hongyo, MD
Katsuyuki Aozasa, MD
John K.C. Chan, MBBS

Hum Pathol 2002;32:103-1407. Abstract quote

Adenoid cystic carcinoma is an indolent tumour with an unfavorable long-term prognosis. Dedifferentiation of adenoid cystic carcinoma, which is associated with an accelerated clinical course, has recently been described.

We report a case with immunohistochemical and molecular workup to elucidate the likely mechanism of dedifferentiation. The patient, a 64-year-old woman, developed dedifferentiated adenoid cystic carcinoma of the submandibular gland ab initio, accompanied by cervical lymph node metastasis.

Histologically, the low-grade adenoid cystic carcinoma merged gradually into an extensive dedifferentiated component that was composed of solid sheets and cords of anaplastic tumor cells with focal gland formation. Immunohistochemically, the dedifferentiated component, but not the adenoid cyst carcinoma component, showed strong overexpression of p53 protein and cyclin D1, as well as a higher Ki67 index. Molecular study confirmed the presence of p53 gene mutation selectively in the dedifferentiated component, suggesting a pivotal role of p53 gene alteration in the dedifferentiation process of adenoid cystic carcinoma.

The sclerosing variant of adenoid cystic carcinoma. A previously unrecognized neoplasm of major salivary glands.

Albores-Saavedra J, Wu J, Uribe-Uribe N.

Department of Pathology, LSU Health Sciences Center School of Medicine, Shreveport, LA 71130, USA.

Ann Diagn Pathol. 2006 Feb;10(1):1-7. Abstract quote  

We report 2 cases of a previously unrecognized sclerosing variant of adenoid cystic carcinoma (ACC) of major salivary glands.

One of the tumors arose in the parotid and the other in the submaxillary gland of young adult patients. The tumors were composed predominantly of varying-sized large sclerotic and hypocellular nodules containing myoepithelial cells and pseudovascular spaces, most likely the result of artifactual retraction.

In moderately cellular nodules, there were numerous small globules or spherules surrounded by myoepithelial cells similar to those of collagenous or mucinous spherulosis. Focal cribriform areas and ductal structures lined by epithelial cells were also identified. Both tumors showed perineural invasion. Electron microscopy revealed that both large nodules and small globules or spherules were composed of excessive amounts of basement membrane and thick-banded collagen fibers. The myoepithelial cells showed immunoreactivity for smooth muscle actin (SMA), S100 protein, and vimentin. Collagen IV showed variable reactivity in both the large nodules and small spherules.

More cases of the sclerosing variant of ACC and long-term follow-up of the patients are needed to determine the biologic behavior of this unusual but distinctive variant of ACC.


Special stains Pseudocysts are alcian blue positive
Chondroitin sulfate and heparan sulfate positive
Immunoperoxidase S100 positive
Keratin and vimentin co-expression
MSA and myosin positive
Ductal lumina positive for CEA

The myoepithelial immunophenotype in 135 benign and malignant salivary gland tumors other than pleomorphic adenoma.

Prasad AR, Savera AT, Gown AM, Zarbo RJ.

Henry Ford Hospital, Detroit, MI 48202, USA.

Arch Pathol Lab Med 1999 Sep;123(9):801-6 Abstact quote

BACKGROUND: We have previously studied the immunoreactivity of 3 novel smooth muscle-specific proteins, alpha-smooth muscle actin, smooth muscle myosin heavy chains, and calponin, to assess myoepithelial differentiation in pleomorphic adenomas.

OBJECTIVE: To further expand our knowledge of myoepithelial differentiation in other benign and malignant salivary gland tumors.

DESIGN: Formalin-fixed paraffin sections of 135 salivary gland tumors with associated normal glands were stained with monoclonal antibodies using the avidin-biotin complex immunoperoxidase method and enzymatic and microwave heat-induced epitope retrieval.

RESULTS: In adenoid cystic carcinomas and epithelial-myoepithelial carcinomas, all 3 markers exclusively highlighted the myoepithelial cell components and the epithelial cells were entirely negative. No immunostaining was detected in canalicular adenomas, oncocytomas, Warthin tumors, acinic cell carcinomas, mucoepidermoid carcinomas, squamous cell carcinomas, and polymorphous low-grade adenocarcinomas. Salivary duct carcinomas and adenocarcinomas, not otherwise specified had a distinctive pattern of uniform periductal staining of reactive myofibroblastic cells, and in salivary duct carcinomas some ducts retained a peripheral immunoreactive myoepithelial cell layer.

CONCLUSION: Immunoreactivity for these 3 smooth muscle-specific proteins confirms the known neoplastic myoepithelial component of adenoid cystic carcinomas and epithelial-myoepithelial carcinomas. The consistently positive staining pattern in adenoid cystic carcinomas may be diagnostically useful in discriminating histologically similar but consistently negative polymorphous low-grade adenocarcinomas. Periductal linear staining in adenocarcinoma, not otherwise specified and salivary duct carcinomas is distinctive and appears to represent a tight cuff of myofibroblasts associated with the infiltrating glands.

CD117 (C-kit)  

Expression of KIT (CD117) in neoplasms of the head and neck: an ancillary marker for adenoid cystic carcinoma.

Mino M, Pilch BZ, Faquin WC.

Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
Mod Pathol. 2003 Dec;16(12):1224-31. Abstract quote  

Adenoid cystic carcinoma is an indolent salivary gland malignancy that is associated with a poor long-term prognosis. The distinction of adenoid cystic carcinoma from other head and neck neoplasms can occasionally be problematic, particularly in small biopsies.

Recent studies suggest that KIT (CD117) might be useful as an ancillary marker for adenoid cystic carcinoma; however, the expression of KIT in other benign and malignant head and neck neoplasms, including those that might mimic adenoid cystic carcinoma, has not been well studied. Here we use two different antibodies against KIT to evaluate its expression in a series of 66 adenoid cystic carcinomas compared with its expression in 98 other neoplasms of the head and neck. Overall, 94% (n = 62) of adenoid cystic carcinomas from various anatomic sites and of various histologic subtypes were positive for at least one of the KIT antibodies, and 77% (n = 50) of adenoid cystic carcinoma cases were positive for both antibodies. This contrasted with only 8% (n = 8) of other head and neck neoplasms that were positive for both KIT antibodies (P <.001). It was of note that certain neoplasms, including pleomorphic adenoma, basal cell adenoma, polymorphous low-grade adenocarcinoma, and basal cell carcinoma, that can show histologic overlap with adenoid cystic carcinoma had significantly less KIT immunoreactivity than did adenoid cystic carcinoma (P <.001).

In contrast, KIT expression did not reliably distinguish adenoid cystic carcinoma from basal cell adenocarcinoma and basaloid squamous carcinoma (P >.05). The overall sensitivity of the two KIT antibodies for adenoid cystic carcinoma was 82-89%, and the specificity was 87-88%.

The findings in this study support the potential use of KIT immunoexpression for distinguishing adenoid cystic carcinoma from many other benign and malignant head and neck neoplasms.

C-kit Expression Distinguishes Salivary Gland Adenoid Cystic Carcinoma from Polymorphous Low-Grade Adenocarcinoma.

Penner CR, Folpe AL, Budnick SD.

Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia.

Mod Pathol 2002 Jul;15(7):687-91 Abstract quote

Adenoid cystic carcinoma (ACC) is characterized by persistent, relentless growth and a high rate of eventual metastasis. In contrast, polymorphous low-grade adenocarcinoma (PLGA) has a much lower risk of recurrence and rarely metastasizes. The histologic patterns of these two neoplasms can be similar. Expression of c-kit, a transmembrane receptor tyrosine kinase, has recently been reported to be expressed in ACC but not PLGA. Expression of galectin-3, a nonintegrin beta-galactosidase-binding lectin, has been reported to be significant in PLGA and decreased in ACC.

Formalin-fixed paraffin-embedded tissue from 9 ACC and 14 PLGA were immunostained for c-kit and galectin-3. Cases were scored as 1+ (5-25% positive), 2+ (26-50% positive), or 3+ (>50% positive). C-kit was expressed by 100% of ACC (3+: 7 cases; 2+: 1 case; 1+: 1 case) and by 57% of PLGA (2+: 2 cases; 1+: 6 cases). In all but one ACC, c-kit expression was confined to the inner cell layer. C-kit expression was also noted in the intercalated duct epithelium of the salivary glands and the acinar cells of the lacrimal gland. Galectin-3 was expressed in 8 of 9 cases of ACC and 14 of 14 cases of PLGA.The results of this, the first study to compare c-kit and galectin-3 expression in ACC and PLGA, suggest that c-kit expression characterizes ACC, but not PLGA. Galectin-3 immunohistochemistry does not have a role in the differentiation of ACC and PLGA. C-kit immunostaining may be a valuable adjunctive tool for this differential diagnosis, particularly in the setting of a limited biopsy.

Our finding of different patterns of c-kit expression in tubular and solid variants of ACC supports the concept of solid variant ACC as a high-grade tumor, with progression toward an entirely "inner cell" phenotype.

p63 Immunohistochemistry in the distinction of adenoid cystic carcinoma from basaloid squamous cell carcinoma.

Emanuel P, Wang B, Wu M, Burstein DE.

1Department of Pathology, Mount Sinai School of Medicine, New York, NY, USA.

Mod Pathol. 2005;18:645-650 Abstract quote

Morphologic distinction of high-grade adenoid cystic carcinoma from basaloid squamous cell carcinoma can be difficult. Equivocal diagnoses can mislead treatment.

We have investigated the possibility that immunohistochemical staining for the presence of p63, a novel epithelial stem-cell regulatory protein, could be a useful means of distinguishing these two neoplasms. Archival, routinely processed slides were subjected to citrate-based antigen retrieval, exposure to anti-p63 monoclonal 4A4, and developed with a streptavidin-biotin kit and diaminobenzidine as chromogen. p63 was detected in 100% of the adenoid cystic carcinomas (n=14) and 100% of basaloid squamous cell carcinomas (n=16). Basaloid squamous cell carcinomas consistently displayed diffuse p63 positivity, with staining of nearly 100% of tumor cells. In contrast, adenoid cystic carcinoma displayed a consistently compartmentalized pattern within tumor nests.

Compartmentalization was manifested in two patterns: (1) selective staining of a single peripheral layer of p63-positive cells surrounding centrally located tumor cells that were p63-negative and (2) tumor nests consisting of multiple contiguous glandular/cribriform-like units of p63-positive cells surrounding or interspersed with p63-negative cells.

p63 immunostaining constitutes a specific and accurate means of distinguishing adenoid cystic carcinoma from basaloid squamous cell carcinoma. p63 positivity in adenoid cystic carcinoma appears to be homologous to that seen in the basal and/or myoepithelial compartments of salivary gland and other epithelia, and may signify a stem-cell-like role for these peripheral cells. Diffuse p63 positivity in basaloid squamous cell carcinoma suggests dysregulation of p63-positive stem cells in poorly differentiated squamous carcinoma.
Electron microscopy (EM) Bidirectional differentiation with luminal (ductal) and abluminal (myoepithelial and basal) cells


Polymorphous low grade adenocarcinoma  

The cribriform features of adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma: Cytokeratin and integrin expression

Vera C. Araújo, DDS, PhD
Silvia V.L. Loducca, DDS, PhD
Suzana O.M. Sousa, DDS, PhD
David M. Williams, DDS, PhD
Ney S. Araújo, DDS, PhD

Ann Diagn Pathol 2001;5:330-334 Abstract quote

Cribriform areas are common features of both adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma. Both are malignant salivary gland tumors that share similar histologic patterns, but with marked distinct clinical behavior.

This study was undertaken to improve the accuracy of the histopathology diagnostic process, using an immunohistochemical panel to differentiate adenoid cystic carcinoma from polymorphous low-grade adenocarcinoma, with special concern to the common cribriform areas shared by these tumors. Three-µm serial sections of these tumors were submitted to the streptavidin-biotin peroxidase immunotechnique against the monoclonal antibodies anticytokeratins 7, 8, 14 and 19, and anti-integrins 1, 3, and 4. In the neoplastic lobules of adenoid cystic carcinoma cribriform type, the spaces were mainly surrounded by cells negative for the cytokeratins and integrins studied. In the solid type of adenoid cystic carcinoma, the microcystic areas were caused by spaces lined by neoplastic luminal cells positive for cytokeratins and presenting integrins concentrated in the apical pole of these cells. The cribriform areas of polymorphous low-grade adenocarcinoma were composed of cords of luminal cells, positive for cytokeratins and showing integrins disposed in a bipolar pattern.

We concluded that cribriform areas of adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma are histologically similar, although not identical. Indeed, their cellular composition is distinct and can be distinguishable from one another by the proteins of the cytoskeleton, by the integrins, or both.

Epithelial-myoepithelial carcinoma  
Basaloid squamous cell carcinoma Usually with nucleoli and may have an situ squamous cell carcinoma
Vimentin, muscle specific actin negative
Positive cervical lymph nodes
Adenoid Cystic Carcinoma
A Pitfall in Aspiration Cytology of the Thyroid

Michael O. Idowu, MD
Am J Clin Pathol 2004;121:551-556 Abstract quote

While adenoid cystic carcinoma is not an uncommon tumor in the salivary glands, its occurrence in the larynx and trachea is rare. Extension of an adenoid cystic carcinoma of the larynx and trachea to the thyroid with manifestation as a thyroid nodule is extremely rare.

However, this possibility always should be considered whenever there are cytologic features suggestive of adenoid cystic carcinoma in thyroid aspirates and when there is a history of adenoid cystic carcinoma in the trachea or larynx or in any part of the body.



There is not a strong correlation between histologic subtype and behavior.

Some argue that tubular and cribriform types have a better prognosis

Poor prognostic factors:

Size and presence of metastases are the most important prognostic factors
Gross residual tumor after surgery

Cell proliferation in salivary gland adenocarcinomas with myoepithelial participation. A study of 78 cases.

Fonseca I, Felix A, Soares J.

Departamento de Patologia Morfologica & Centro de Investigacao de Patobiologia Molecular (CIPM), Instituto Portugues de Oncologia de Francisco Gentil, Lisboa, Portugal.

Virchows Arch 1997 Mar;430(3):227-32 Abstract quote

We used three markers of cell proliferation mitotic counts, mitotic index and expression of proliferating cell nuclear antigen--to assess the proliferative activity of a series of 78 low-grade salivary adenocarcinomas with myoepithelial participation classified according to: their histological type, the predominant architectural type, and the predominant cytological type. The series included adenoid cystic carcinomas (40), epithelial-myoepithelial carcinomas (19), polymorphous low-grade adenocarcinomas (12) and basal cell adenocarcinomas (7).

The proliferation indicators were found to be similar in the first three groups, being significantly lower than in the last. Tumours formed by basal cells had statistically significant higher mitotic indexes than those predominantly composed of clear cells of myoepithelial type and ductal cells. Tubular tumours, irrespective of the histological classification of the neoplasm, had proliferation indexes similar to those found in cribriform neoplasms. Solid tumours, whether formed by ductal or clear myoepithelial-type cells, had higher indexes than the neoplasms with differentiated (cribriform and tubular) patterns. The highest mean values for every proliferation indicator used were found in tumours with solid organization that were predominantly formed by basal cells. These results agree with the hypothesis that cell proliferation is inversely related to neoplastic differentiation.

The identification of the prevalent cell phenotype and architecture may extend our knowledge from adenoid cystic carcinoma, whose solid variant carries a worse prognosis, and supports that the usual classification of this group of salivary adenocarcinomas would benefit to be complemented with information on tumour architecture and cellular composition.

Survival Once distant metastases has occurred, about 20% of patients may survive from 5-14 years. However, 33% of patients usually die within less than 2 years after distant metastases.

Blood borne metastases in 40-60% are common with the lung being the recipient in 40% of cases. Unlike other salivary gland carcinomas, lymph node metastases are uncommon.

TREATMENT Wide to radical excision with postoperative radiation therapy

Henry JB. Clinical Diagnosis and Management by Laboratory Methods. Twentieth Edition. WB Saunders. 2001.
Rosai J. Ackerman's Surgical Pathology. Ninth Edition. Mosby 2004.
Sternberg S. Diagnostic Surgical Pathology. Fourth Edition. Lipincott Williams and Wilkins 2004.
Robbins Pathologic Basis of Disease. Seventh Edition. WB Saunders 2005.
DeMay RM. The Art and Science of Cytopathology. Volume 1 and 2. ASCP Press. 1996.
Weedon D. Weedon's Skin Pathology Second Edition. Churchill Livingstone. 2002
Fitzpatrick's Dermatology in General Medicine. 6th Edition. McGraw-Hill. 2003.
Weiss SW and Goldblum JR. Enzinger and Weiss's Soft Tissue Tumors. Fourth Edition. Mosby 2001.

Hum Pathol 1996;27:567-572.

Commonly Used Terms

Basic Principles of Disease
Learn the basic disease classifications of cancers, infections, and inflammation

Commonly Used Terms
This is a glossary of terms often found in a pathology report.

Diagnostic Process
Learn how a pathologist makes a diagnosis using a microscope

Surgical Pathology Report
Examine an actual biopsy report to understand what each section means

Special Stains
Understand the tools the pathologist utilizes to aid in the diagnosis

How Accurate is My Report?
Pathologists actively oversee every area of the laboratory to ensure your report is accurate

Got Path?
Recent teaching cases and lectures presented in conferences

Internet Links

Last Updated February 8, 2006

Send mail to The Doctor's Doctor with questions or comments about this web site.
Read the Medical Disclaimer.

Copyright © The Doctor's Doctor