The role of p53 mutation and protein expression in primary and recurrent adenoid cystic carcinoma

Adenoid cystic carcinoma (ACC) is a malignant tumor of salivary gland origin having a propensity for spread by direct extension or perineural invasion with frequent recurrences. Previous reports have shown that tumor behavior is not always predicted by histological pattern or stage. Little is known of the role of p53 tumor suppressor gene mutation and altered protein expression with respect to ACC pathobiology and recurrence. The authors analyzed a group of 14 ACC specimens (seven primary; seven recurrent) from 13 patients treated between 1987 to 1993. Formalin-fixed, paraffin-embedded specimens were reviewed and subjected to, immunohistochemistry (p53, DO-7, DAKO, Nutley, NJ; and WAF-I, Ab-1, Oncogene Sciences, Uniondale, NY) on 4-microm-thick histological sections as a prelude to p53 genotyping. In one case, sequential material representing primary and recurrent tumor was analyzed. Each tumor specimen was topographically genotyped for p53 point mutational change. Minute tissue samples were removed from unstained sections, polymerase chain reaction (PCR) amplified for p53 exons 5 to 8, and then underwent direct DNA sequencing. Six of seven primary ACCs were p53 immunostain negative. Four of seven recurrent (57%) ACCs were p53 immunopositive. These tumors showed varying degrees of p53 immunopositivity ranging from diffuse, intense staining of most tumor cells (n = 1) to interspersed, strongly positive cells mixed with predominantly p53 immunonegative cells (n = 4). All tumors were WAF-I immunostain negative. Two of the most immunopositive recurrent tumors each manifested a single type of p53 point mutation detected by p53 DNA genotyping (p53 exon 5:codon 175 and p53 exon 6:codon 199). In the case in which both primary and recurrent tumor was available, only the recurrent tumor contained point mutational damage. Negative immunostaining for p53 in primary ACC suggests that p53 mutation is not important in early events involving development of this tumor. In contrast, the frequent presence of p53-positive cells and the detection of point mutations in recurrent ACC suggests that p53 alterations are involved in later stages of tumor progression, important in the phenomenon of ACC recurrence.

Over-expression of glutathione S-transferases, DT-diaphorase and an apparently tumour-specific cytosolic class-3 aldehyde dehydrogenase by Warthin tumours and mucoepidermoid carcinomas of the human parotid gland

Cytosolic class-3 aldehyde dehydrogenase (ALDH-3) may help to protect organisms from certain environmental aldehydes by catalysing their detoxification. Consistent with this notion are the reports that relatively high levels of this enzyme are present in tissues, e.g. stomach mucosa and lung, that are so-called ports of entry for such agents. Further, it is found in human saliva. The present investigation revealed that small amounts of this enzyme are also present in human salivary glands; mean values for ALDH-3 activities (NADP-dependent enzyme-catalysed oxidation of benzaldehyde) in cytosolic fractions prepared from submandibular and parotid glands were 52 (range: 29-92) and 44 (range: 13-73) mIU/g tissue, respectively. Essentially identical or slightly lower levels of this enzyme activity were found in pleomorphic adenomas, an undifferentiated carcinoma, and an adenocystic carcinomas, of the parotid gland. On the other hand, Warthin tumours, and mucoepidermoid carcinomas of the parotid gland exhibited relatively elevated levels of ALDH-3 activity; mean values were 1200 (range: 780-1880) and 810 (range: 580-1200) mIU/g tissue, respectively. The ALDH-3 found in normal salivary glands was, as judged by physical, immunological and kinetic criteria, identical to human stomach mucosa ALDH-3 whereas the ALDH-3 present in Warthin tumours, and mucoepidermoid carcinomas, of the parotid gland appeared to be a subtle variant thereof. Qualitatively paralleling the relatively elevated ALDH-3 levels in mucoepidermoid carcinomas and Warthin tumours were relatively elevated levels of glutathione S-transferase (alpha and pi) and DT-diaphorase. As was the case with ALDH-3 levels, glutathione S-transferase (alpha and pi) and DT-diaphorase levels were not elevated in pleomorphic adenomas. Glutathione S-transferase mu was not detected in the two normal parotid gland samples, or in the single pleomorphic adenoma sample, tested. It was found in the single mucoepidermoid carcinoma sample, and in one of the two Warthin tumour samples tested. Cellular levels of ALDH-3, glutathione S-transferases and/or DT-diaphorase could be useful criteria when the decision to be made is whether a salivary gland tumour is a mucoepidermoid carcinoma. ALDH-3 and glutathione S-transferases are known to catalyse the detoxification of two agents that are used to treat salivary gland tumours, viz. cyclophosphamide and cisplatin, respectively. Thus, elevated levels of these enzymes in the mucoepidermoid carcinomas must account for, or at least contribute to, the relative ineffectiveness of these agents when used to treat this tumour.

The cylindromatosis gene (cyld1) on chromosome 16q may be the only tumour suppressor gene involved in the development of cylindromas

Hereditary cylindromatosis is a rare autosomal dominant disease characterised by the development of multiple benign neoplasms of the skin. We recently localised the gene responsible for this disease (cyld1) to chromosome 16q12-q13 and provided evidence that it is a tumour suppressor gene (Biggs et al., 1995). We have now examined polymorphic markers on every chromosome, some of which are close to known tumour suppressor genes, in 25 tumours from 4 individuals with familial cylindromatosis. No loss of heterozygosity (LOH) was detected other than at loci on chromosome 16q. This observation suggests that the cyld1 gene may be the only tumour suppressor gene implicated in the development of cylindromas. We have also demonstrated LOH using markers on chromosome 16q in 8/14 (57%) sporadic cylindromas, indicating that the cyld1 gene is likely to be involved in the genesis of both familial and sporadic cylindromas.

Proliferative activity and p53 expression in adenoid cystic carcinoma of the breast

Adenoid cystic carcinoma is a rare type of invasive breast carcinoma that has a good prognosis. We studied a series of four cases of adenoid cystic carcinoma in which we correlated the clinical and pathological features. The pathological features examined included light microscopy; electron microscopy; immunohistochemistry using antibodies to keratin, vimentin, S100 protein, actin, estrogen and progesterone receptors, and proliferation marker MiB-1, and p53 suppressor protein; image cytometric analysis for measurement of DNA ploidy; and molecular analysis using polymerase chain reaction single strand conformation polymorphism to assess point mutation of the p53 gene. All of the cases had a low nuclear grade, were negative for estrogen and progesterone receptors, and were DNA diploid. Three of the cases showed no evidence of metastases and had small primary tumors with low proliferative activity and absence of p53 protein expression. In contrast, one of the cases showed axillary lymph node metastases and in this case the primary tumor was large with a higher proliferative activity and expression of p53 protein, suggesting that these factors might play a role in the biological behavior of adenoid cystic carcinoma.

Pleomorphic adenoma and adenoid-cystic carcinoma of salivary glands: immunohistochemical assessment of proliferative activity in comparison with flow-cytometric study

In this study, 32 pleomorphic adenomas (PAs) and seven adenoid cystic carcinomas (ACCs) were analysed for the evaluation of proliferating cell nuclear antigen (PCNA) indices and flow cytometric variables. Our aim was to assess any possible relationship between these parameters and the clinico-pathological variables and to clarify their histogenesis and reasons for their biological differences. The tumours were divided into three groups, mainly epithelial (E), myxoid (M) and chondroid (C); PCNA labelling index (LI) and weighted mean index (WI) and the WI/LI ratio were analysed in the predominant components; a single PCNA index, weighted by the percentage of each component, was also calculated. Only WI/LI was found to be significantly different in the three components, while PCNA single index did not show either significant differences by sex, age, site and size, or any correlation with the S phase fraction. A significant difference was found between PAs and ACCs by site (P < 0.01) and DNA ploidy (P < 0.05); furthermore, all PCNA indices (single index) were significantly lower in PAs than in ACCs.

Familial cylindromatosis (turban tumour syndrome) gene localised to chromosome 16q12-q13: evidence for its role as a tumour suppressor gene

The human skin is a complex organ composed of the surface epidermis, the subjacent dermis (in which blood vessels, lymphatics and nerves are located) and the skin appendages. The latter include hair follicles, sebaceous glands (which secrete lipids that may serve as a permeability barrier, emollient or antimicrobial agent), apocrine glands (which secrete scents) and eccrine glands (which produce sweat for temperature control). Hereditary cylindromatosis (MIM 123850) is a rare autosomal dominant disease characterised by the development of multiple neoplasms originating from the skin appendages. These neoplasms have been termed cylindromas due to their characteristic microscopic architecture and are believed to exhibit apocrine or eccrine differentiation. We have carried out a genome search using two families with this disease, which has provided strong evidence for linkage of cylindromatosis to loci on chromosome 16q12-q13. Using markers close to the cylindromatosis gene, consistent loss of the wild-type allele was observed in 19 tumours from four individuals in the two families, indicating that the gene is likely to be a tumour suppressor gene.

Expression of c-erbB family gene products in adenoid cystic carcinoma of salivary glands: an immunohistochemical study

The tyrosine kinase receptor family, including the epidermal growth factor receptor (EGF-R), c-erbB2 and, more recently, the c-erbB3, has been recognized as being of particular importance in many human malignancies. This study was undertaken to define the role of c-erb B2 and c-erbB3 in adenoid cystic carcinomas (A.C.C.) of the salivary glands. Sixteen cases of A.C.C. were studied immunohistochemically, using antibodies against each erbB gene family product. EGF-R was not detected in any of these samples but c-erbB2 and c-erbB3 gene products (ERBB2and ERBB3) were demonstrated in all A.C.C. sections with some degree of straining. Tubular and cribriform patterns overexpressed particularly large amounts of ERBB2 and ERBB3. Strong staining was mainly demonstrated in tumor cells of the invasive area. These results suggested that overexpression of ERBB2 and ERBB3 is related to tumor differentiation and invasion in adenoid cystic carcinomas.

A fluorescence in situ hybridization (FISH) analysis with centromere-specific DNA probes of chromosomes 3 and 17 in pleomorphic adenomas and adenoid cystic carcinomas

Aberrations of chromosomes 3 and 17 were studied by FISH using centromere-specific DNA probes in 11 salivary adenoid cystic carcinomas (ACC) and 8 salivary pleomorphic adenomas (PA), with 3 lymph nodes as controls. Two hybridized signals were detected in 92.8 +/- 2.7% of controls, 73.2 +/- 7.0% of PA and 66.8 +/- 7.9% of ACC cells for chromosome 3, and in 90.4 +/- 2.3% of controls, 59.5 +/- 25.0% of PA and 44.8 +/- 20.2% of ACC for chromosome 17. More than 3 hybridized signals, which indicate polysomy, were observed in 3.1% of controls, 15.5% of PA and 22.9% of ACC cells for chromosome 3, and in 1.2% of controls, 10.3% of PA and 23.1% of ACC cells for chromosome 17. A single hybridized signal was much more frequent for chromosome 17 than for chromosome 3. These findings suggest that polysomy of both chromosomes occurs during the development of salivary gland tumors, and its frequency is increased in adenoid cystic carcinoma as compared to pleomorphic adenoma. In addition, monosomy of chromosome 17 could possibly be significant in salivary gland tumors.

Adenoid cystic carcinoma: significance of DNA ploidy

BACKGROUND

DNA ploidy pattern is sometimes used as a prognostic factor. Heterogeneity of a tumor could, however, give false information when a single analysis is performed.

METHODS

Twenty-eight patients with adenoid cystic carcinomas were retrospectively studied with regard to clinico-histologic parameters, and in 24 of these the DNA pattern was assessed using flow cytometry, with multiple analysis from different tumor parts, to determine prognostic factors.

RESULTS

Of the carcinomas, 33% (8/24) were DNA aneuploid, and 17% (4/24) of the tumors showed intratumoral heterogeneity of DNA content; two of them with mixture of diploid and aneuploid stemlines. The DNA aneuploid tumors were clinically more advanced and demonstrated a higher frequency of solid architecture than did diploid tumors (p < 0.05). The S-phase values were significantly higher in aneuploid samples than in diploid ones (p < 0.05). The recurrence rate was significantly higher in patients with aneuploid tumors (75%) than with diploid ones (19%) (p < 0.05). The cumulative survival was worse for patients with aneuploid tumors than for those with diploid ones (p < 0.05).

CONCLUSIONS

Our findings suggest a potentially important role for flow cytometry in evaluation of adenoid cystic carcinoma. It is of interest to observe that in some tumors both diploid and aneuploid stemlines can co-exist. If one sample is analyzed and demonstrates diploid cells, there is a 3% chance that the tumor is also heterogeneous with aneuploid stemlines. If one sample demonstrates aneuploid cells, there is a 7% chance for heterogeneity with diploid cells, as well. Two samples from different tumor parts can be considered representative.

c-erbB-2/neu Oncogene and Ki-67 Analysis in the Assessment of Palatal Salivary Gland Neoplasms

To evaluate the role of the Ki-67 proliferation antigen and c-erbB-2/neu oncogene expression in the clinical assessment of salivary gland tumors, we followed up 71 patients with minor salivary tumors of the palate. All benign neoplasms ( n= 18) showed low Ki-67 scores (< 12%), whereas 26% (14 of 53) of malignant neoplasms manifested high Ki-67 scores (<12%). A significant statistical difference between Ki-67 scores for benign and malignant neoplasms was observed ( p < 0.001). Ki-67 index also correlated significantly with malignant tumor grade ( p = 0.04) and patient survival ( p = 0.02). Only 1 of the 18 benign tumors had c-erbB-2/neu oncogene overexpression. A significant difference between c-erbB-2/neu overexpression in benign and malignant tumors was observed ( p = 0.01). Overexpression of c-erbB-2/neu oncogene was noted in 38% (16 of 42) of malignant tumors and was significantly associated with aggressive tumor behavior ( p <0.001). Multivariate analysis of significant factors revealed that gender, tumor stage, and c-erbB-2/neu oncogene overexpression were jointly predictive of survival. Our data indicate that although the Ki-67 proliferating antigen and c-erbB-2/neu oncogene expression may reflect certain intrinsic biologic properties of these neoplasms, only c-erbB-2/neu overexpression is significantly associated with their biologic aggression.

DNA content in adenoid cystic carcinomas

BACKGROUND

A retrospective study was performed on 51 patients with adenoid cystic carcinomas to see whether DNA ploidy, tumor stage, and histopathologic grading correlated with prognosis.

METHODS

Histopathologic grading was performed according to Szanto et al and DNA content was estimated from archived material using the technique by Hedley et al.

RESULTS

Thirty-nine tumors were DNA diploid and 12 were DNA aneuploid. Histologic grade III was more often associated with DNA aneuploidy than the lower grades (p = 0.011). DNA ploidy also correlated with clinical stage (p = 0.011). Log-rank analysis and Cox regression analysis of treatment failures revealed significant findings for S-phase value and DNA ploidy.

CONCLUSIONS

Our results indicate that DNA ploidy estimations, S-phase value, and histologic grading are prognostic factors in adenoid cystic carcinomas. These examinations should therefore be incorporated in the evaluation of patients with adenoid cystic carcinomas.

DNA flow cytometry of reclassified subtypes of malignant salivary gland tumors

Malignant salivary gland tumors are rare, constitute a heterogeneous group and are often difficult to diagnose histologically. This is borne out by the fact that in the present study 43.2% of 118 salivary gland tumors originally diagnosed as mucoepidermoid, acinic cell and adenoid cystic carcinomas had their original diagnosis altered upon reclassification. Patients with confirmed adenoid cystic carcinomas had a much worse prognosis than those with mucoepidermoid and acinic cell carcinomas. DNA flow cytometry showed that very few of the above mentioned three types of malignant neoplasms revealed aneuploid DNA stemlines, indicating that this is not a relevant prognostic tumor marker within the groups. However, several of the tumors that had their diagnosis changed, mostly to undifferentiated adeno- or squamous cell carcinomas, showed aneuploid DNA stemlines. The survival time of patients with aneuploid tumors was considerably reduced compared to those with diploid tumors. Among confirmed acinic cell, mucoepidermoid and adenoid cystic carcinomas the S-phase fraction was a significant prognostic factor, as it was among all tumors examined. This indicates that DNA aneuploidy and S-phase fractions are potential prognostic factors for malignant salivary gland tumors, and that DNA flow cytometry may assist the characterization of such tumors.

Cytogenetic findings in seven lacrimal gland neoplasms

We have undertaken cytogenetic investigation of seven benign and malignant lacrimal gland neoplasms. This study showed recurrent chromosomal abnormalities involving chromosomes 3, 8, 9, and 12. These features are similar to those found in benign and malignant salivary gland tumors, which suggests possible common mechanisms involved in the neoplastic proliferation of these histologically related tumors.

Cytogenetic findings in a new case of adenoid cystic carcinoma arising in sphenoidal sinus

We studied a case of adenoid cystic carcinoma. Cytogenetic analysis was performed on short-term culture, and the karyotype revealed only an abnormal cell line with the following changes: partial trisomy 5q, 6q deletion, monosomy of chromosome 9,der(10)t(10;15), a possible ring chromosome 22, and loss of the Y chromosome. The implication of chromosomes 6 and 9 is considered in relation to the karyotypic evolution of this type of tumor.

Characteristic karyotypic features in lacrimal and salivary gland carcinomas

Short-term cultures from 12 non-squamous cell carcinomas (NSCCs) of the head and neck were cytogenetically investigated. Three tumours were acinic cell carcinomas, two adenoid cystic carcinomas, three mucoepidermoid carcinomas, two carcinomas in pleomorphic adenoma, and two adenocarcinomas. Clonal chromosome aberrations were detected in all but one adenocarcinoma. Including our data, a total of 40 head and neck NSCCs with clonal aberrations have been described. Deletions of the long arm of chromosome 6 are the most common aberrations (11/40 cases); they have been detected in all types of NSCC except carcinoma in pleomorphic adenoma. Two aberrations seem to be closely associated with tumour type: t(6;9)(q21-24;p13-23), which has been seen in three of 11 adenoid cystic carcinomas (in two as the sole aberration), and structural rearrangements of 8q12-13, which have been detected in three of four carcinomas in pleomorphic adenoma.

Non-random chromosome rearrangements in adenoid cystic carcinoma of the salivary glands

The chromosomal findings in 10 adenoid cystic carcinomas (ACC) of the salivary glands are described. Clonal numerical deviations as the sole anomaly were detected in four cases and structurally rearranged stemlines and sidelines in four cases. An apparently identical t(6;9)(q23;p21) was found in two tumors; in one case the translocation was part of the abnormal stemline and in the other case it was the sole anomaly in a single variant cell. A similar or identical t(6;9)(q21-24;p13-23) has recently been reported in three of 15 previously published cases of ACC. The three remaining tumors with abnormal stemlines all had rearrangements of chromosome 9, including t(1;9)(q21;p21-22), der(9)i(9)(q10)inv(9)(q12q13), and der(X)t(X;9)(p21;p22-23), respectively. The latter case also had a t(17;18)(p12;q11.2) that was common to both abnormal clones present in this tumor. In addition to other abnormalities, the clone with der(X)t(X;9) also showed a del(6)(q13q21). In two cases fluorescence in situ hybridization (FISH) was used for further characterization of the marker chromosomes. A survey of the present findings together with previous results from 15 ACC clearly demonstrates that rearrangements of 6q21-24 (deletions or translocations in 11 cases), 9p13-23 (translocations in seven cases), and 17p12-13 (translocations in three cases) are recurrent, and often primary, in ACC, and that the t(6;9)(q21-24;p13-23), found in five tumors, is a non-random, primary aberration.

[Study on the salivary adenoid cystic carcinoma with the flow cytometric analysis]

The cellular DNA content of 28 cases of salivary adenoid cystic carcinoma (SACC) were quantified with the flow cytometric analysis. The result showed that majority of SACC (22/28) were diploidy tumors. No significant correlation between the cellular DNA content and the histopathologic appearances, the cellular DNA content and the clinical behavior of SACC was found.

Salivary neoplasms of the palate: a flow cytometric and clinicopathological analysis

In order to test the clinical and prognostic significance of flow cytometrically assessed DNA content in minor salivary gland tumours we evaluated 75 neoplasms of the palate, 55 of which were carcinomas. Benign neoplasms were exclusively DNA diploid with low S-phase fractions while 22 per cent of malignant tumours manifested a DNA aneuploidy and 23.5 per cent high S-phase fractions (> 5 per cent). Significant statistical correlations between DNA content and tumour size, histological grade, lymph node metastasis and lethality were observed. Our findings suggest a potentially important role for flow-cytometry in the evaluation of these neoplasms.

Cutaneous cylindroma with malignant transformation

BACKGROUND

Malignant cutaneous cylindroma is a rare tumor. It has been described in 26 cases, both in the solitary form and in the autosomal dominant inherited multiple tumor form. The authors present two new cases that occurred in one family with a history of multiple cylindromas.

METHODS

Clinical and histopathologic data of both tumors were compared with those of 26 other cases in the literature. Immunohistochemical examinations were performed.

RESULTS

The malignant tumors were distinguished from the benign lesions by rapid growth, long-standing ulceration, or bleeding. Histopathologic examination showed a well-differentiated carcinoma in one patient and a poorly differentiated tumor in the other. In the latter, lymph node metastasis developed, and the patient died 2.5 years later. Histopathologic criteria of malignancy included cell pleomorphism, frequent mitoses and loss of jigsaw pattern, peripheral palisading, hyaline sheaths, and dual cell population.

CONCLUSIONS

These observations are in accord with those in the literature. Malignant cutaneous cylindroma developed more often in the multiple tumor form than in the single tumor form. Malignant cylindroma is an aggressive carcinoma with a tendency to local destructive growth and metastases.

[Significance of aberrant p53 protein in head-neck tumors and its effect on proliferation and differentiation]

Mutation of the tumor suppressor gene p53 is the most frequent genetic alteration of human tumors. Our systematic immunohistochemical analysis of the p53 phenotype and the comparison to proliferation and differentiation has revealed that over 50% of the squamous cell carcinomas of the head and neck show p53 accumulation of aberrant p53 protein. Normal epithelia did not show p53 accumulation and benign lesions only in exceptional cases. Expression of aberrant p53 was invariably confined to dysplastic cells in close vicinity to the tumor and to invasive, dedifferentiated tumor cells with high proliferative potential, as revealed by expression of the histone H3 gene and of the simple epithelial type cytokeratins. We discuss the possible clinical value of the immunohistochemical screening of tumor patients for the status of the p53 gene.

Rare expression of the c-erbB-2 oncoprotein in salivary gland tumors: an immunohistochemical study

An immunohistochemical study of c-erbB-2 oncoprotein expression was carried out on 201 cases of primary salivary gland tumors, using a polyclonal antibody, raised to the intracytoplasmic domain of the c-erbB-2 oncogene product. An intense membrane reactivity was observed in one case of sialocarcinoma transformed from pleomorphic adenoma (n = 8) and one case of mucoepidermoid carcinoma (n = 22). A comparative histopathologic evaluation of c-erbB-2 positive tumors showed marked variation in cell size, nuclear pleomorphism, multinucleation, a high mitotic rate and increased lymphoid cell infiltration and an aggressive clinical course with poor survival. The results indicate that c-erbB-2 oncoprotein is rarely expressed in malignant salivary gland tumors. However, the overexpression appears to have a distinct histopathologic feature, but a larger study incorporating histopathology and clinical data would be necessary to correlate the significance of c-erbB-2 oncogene product in salivary malignant tumors.

The clinicopathological features of familial cylindromas and trichoepitheliomas (Brooke-Spiegler syndrome): a report of two families

We have studied four patients from two families and obtained the clinical data from four other affected family members who demonstrated the coexistence of multiple cylindromas and trichoepitheliomas. An autosomal dominant pattern of inheritance with variable penetrance was exhibited in both families, with a female to male ratio of 3:1. The clinical and pathological features of this rare association are discussed.

Cytogenetic analysis of an adenoid cystic carcinoma of the Bartholin's gland. A rare, semimalignant tumor of the female genitourinary tract

Cytogenetic analysis has been performed on short-term cultures from a 56-year-old woman suffering from an adenoid cystic carcinoma of Bartholin's gland. Beside a normal female karyotype, the tumor revealed an abnormal cell line with complex chromosome changes involving the chromosomes 1, 4, 6, 11, 22, and 14. The mainly structural and nonbalanced rearrangements led to the loss of the chromosome segments 1p31----qter, 4q22----q28, 6p12----qter, 11p11.2----pter, 14q24----qter, and 22q13----qter. Clonal numerical aberrations were not observed. To our knowledge, such a tumor has to-date not been cytogenetically investigated.

[Expressions of oncogene products in adenoid cystic carcinomas of salivary glands: immunohistochemical study]

In 43 cases of adenoid cystic carcinomas of the salivary glands (ACC), expressions of the oncogene products such as epidermal growth factor receptor (EGF-R), erbB-2 product, c-myc product and N-myc product were investigated immunohistochemically. First, we confirmed the specificity of the antibodies used with the 13 cell lines. Of the anti-EGF-R antibodies, clone 29. 1. 1 reacted only with A431 but not with the other cell lines overexpressing EGF-R, so that it was most likely to cross-react with the blood type A antigen. Also, the anti-N-myc product antibody revealed the presence of a certain cross-reacting antigen in Lu65. Overexpression of EGF-R was observed in only one case. Nine cases (20.9%) showing tubular and cribriform patterns overexpressed the erbB-2 product, but the signals were mainly localized in the cytoplasm as a granular appearance. Eighteen cases (41.9%) with slight cellular atypia showed an overexpression of the c-myc product. The immunolocalization of the c-myc product was at the nuclei in most cases, or both the nuclei and the cytoplasm in some cases. None of the ACC expressed the N-myc product. It is speculated that the multiple oncogene expressions might be partly related to the acquirement of the differentiated or malignant phenotype in the ACC.