Histopathological analysis of apoptosis, and expression of p53, bcl-2, bax, and Ki-67 in laryngeal squamous cell carcinomas and dysplasia

The expression and significance of AKR1B10 in laryngeal squamous cell carcinoma

Aldosterone reductase family 1 member B10 (AKR1B10) is a nicotinamide adenine dinucleotide phosphate (reduced coenzyme II)-dependent oxidoreductase, and its biological functions include carbonyl detoxification, hormone metabolism, osmotic adjustment, and lipid synthesis. Studies suggested that AKR1B10 is a new biomarker for cancer based on its overexpression in epithelial tumors, such as breast cancer, cervical cancer, and lung cancer. At present, studies on the expression of AKR1B10 in laryngeal cancer have not been reported. However, we found that AKR1B10 is upregulated in laryngeal carcinoma, and its expression was negatively correlated with the degree of differentiation. In addition, AKR1B10 expression was positively correlated with tumor size; lymph node metastasis; alcohol use; and Ki-67, mutant p53, and matrix metalloproteinase 2 expression. AKR1B10 was overexpressed in Hep-2 laryngeal carcinoma cells. Oleanolic acid inhibited AKR1B10 activity and expression in Hep-2 cells and suppressed Hep-2 cell proliferation, migration, and invasion. Therefore, AKR1B10 may be related to the development of laryngeal carcinoma, suggesting its use as a prognostic indicator for laryngeal cancer.

Biomarkers of laryngeal squamous cell carcinoma: a review

Laryngeal carcinoma is the second common malignancy of the upper aerodigestive tract after lung cancer; in most cases is a squamous cell carcinoma, whose risk factors include tobacco smoking and alcohol consumption. Despite therapeutic progress, the five-year overall survival rate for this malignancy has remained nearly 50% and many patients already present metastasis at the time of diagnosis. To date, there are no tools that predict the evolution of laryngeal carcinoma: in this light, during the last years, many studies were planned with the aim to investigate the role played by different biomarkers expressed by larynx cancer, which can help make an early diagnosis, predict disease evolution and direct therapeutic choice. This review aims to summarize these markers and correlating them with disease evolution.

Prognostic value of Bcl-2 expression in squamous cell carcinoma of the larynx: a systematic review

The aim of this systematic review was to determine the prognostic value of Bcl-2 immunostaining in patients affected by laryngeal squamous cell carcinoma. An appropriate search was conducted on PubMed to retrieve articles dealing with this topic. A double cross-check was performed on citations and full-text articles by 2 investigators independently to review all manuscripts and perform a comprehensive quality assessment. Of 115 abstracts identified, 15 articles were included. These studies reported on 1,150 patients with histologically confirmed diagnosis of laryngeal squamous cell carcinoma. Only a few studies showed a statistical correlation between Bcl-2 immunohistochemical expression and at least 1 of the clinical and histopathological parameters considered by the authors. Moreover, these findings were also discordant between them. Overall the studies analyzed suggested that Bcl-2 expression was statistically connected with N stage (2/14), grading (2/14), disease-free survival (3/14) and overall survival (5/14). Interestingly, all of the 3 studies investigating the relation between Bcl-2 and radioresistance showed significant results in terms of recurrence-free survival and overall survival. Our review strongly suggests that the immunohistochemical staining of Bcl-2 does not correlate with tumoral aggressiveness and prognosis of patients affected by laryngeal squamous cell carcinoma and treated with primary surgery. However, an interesting connection of this protein could be demonstrated with tumoral radioresistance. Further, high-quality prospective studies should be carried out to confirm this hypothesis.

The clinical relevance of Ki-67 expression in laryngeal squamous cell carcinoma

The aim of this study was to determine the prognostic value of Ki-67 immunostaining in patients affected by laryngeal squamous cell carcinoma. A systematic review was carried out in a tertiary university referral center. An appropriate string was run on PubMed to retrieve articles dealing with Ki-67 immunohistochemical staining and laryngeal squamous cell carcinoma. A double cross-check was performed on citations and full-text articles by two investigators independently to review all manuscripts and perform a comprehensive quality assessment. Of 85 abstracts identified, 18 articles were included. These studies reported on 1,342 patients with histological confirmed diagnosis of laryngeal squamous cell carcinoma. Most studies showed a statistical association between Ki-67 immunohistochemical expression and at least one of the clinical and histopathological parameters considered by the authors. Overall the studies analyzed suggested that the tumoral proliferative index was statistically connected respectively with T stage (2/18), N stage (4/18), grading (6/18), disease-free survival (10/18) and overall survival (4/18). Our review strongly suggests that immunohistochemical staining of Ki-67 correlates with tumoral aggressiveness and worse prognosis in patients affected by laryngeal squamous cell carcinoma. Further high-quality prospective studies should be carried out to confirm our finding and determine the eventual differences between cancers of specific laryngeal subsites.

Morphometric analysis of Ki-67 and p16 expression in laryngeal precursor lesions

Laryngeal precursor lesions represent areas of altered epithelium with an increased likelihood for progression to squamous cell carcinoma. The exact molecular mechanisms of malignant transformation of laryngeal mucosa are not completely clear, but are certainly due to deregulation of cell proliferation. To assess the potential value of the p16 and Ki-67 as markers of malignant progression, we undertook a retrospective immunohistochemical and morphometric analysis on biopsy specimens from patients with precancerous lesions in the larynx. Morphometric analysis of samples stained with p16 antibody showed epithelial cell positivity in 29 (100 %) of samples with simple hyperplasia, 31 (100 %) samples with basal/parabasal cell hyperplasia, 23 (88 %) samples with atypical hyperplasia and 20 (95 %) samples with in situ carcinoma. There was a significant difference in percentage of p16-positive cells between samples with simple hyperplasia and samples with in situ carcinoma. Morphometric analysis of samples stained with Ki-67 antibody showed epithelial cell positivity in 27 (93 %) of samples with simple hyperplasia, 30 (97 %) samples with basal/parabasal cell hyperplasia, 26 (100 %) samples with atypical hyperplasia and 18 (86 %) samples with in situ carcinoma. There was a significant difference not only in the percentage of Ki-67-positive cells between samples with simple hyperplasia and samples with in situ carcinoma, but also between samples with simple and basal/parabasal cell hyperplasia. Laryngeal epithelial precursor lesions show significantly opposite patterns in p16 and Ki-67 immunopositivity. Simple hyperplasia on average shows 12 % of Ki-67-positive cells and 46 % of p16-positive cells. In situ carcinoma on average shows 23 % of Ki-67-positive cells and 36 % of p16-positive cells.

Ki67, p27 and p53 Expression in Squamous Epithelial Lesions of Larynx

Precise assessment of the biological behavior and progression of squamous epithelial lesions of the larynx with a view to predict the prognosis and therapeutic challenges remains an elusive goal. The knowledge and data regarding the expression of proliferative markers indicating the biological activity in different histological grades of squamous epithelial lesions are lacking till date. To evaluate the relationship between Ki67, p27 and p53 expression as well as topographic distribution of Ki67 with the histological subtypes or grades of laryngeal squamous intraepithelial and invasive lesions. Sixty-two consecutive cases with histologically documented intraepithelial and invasive squamous lesion were studied for Ki67, p27 and p53 expression. Mann-Whitney U, Kruskal-Wallis and Spearman's correlation tests were used for statistical analysis. The mean Ki67 labeling index in hyperplasia, dysplasia and carcinoma were 12.15, 22.03 and 35.53 % respectively and this difference was statistically significant (P < 0.05). There was strong positive correlation between Ki67 labeling index and increasing grades of squamous lesions. p27 expression was progressively decreased and p53 expression was progressively increased as the lesions progressed from hyperplasia to dysplasia and dysplasia to carcinoma. The topographic distribution of Ki67 positive cells increased with progressive grades of dysplasia. The Ki67 labeling index correlates well with the histological grade of both intraepithelial and invasive lesions of the larynx. And the topographic distribution of Ki67 expression depends on the grade of the dysplasia. Hence, Ki67 expression has a definite role in predicting the biological behavior of the lesions.

Transcriptional activities of histone H3, cyclin D1 and claudin 7 encoding genes in laryngeal cancer

Uncontrolled proliferation and a decrease in cell-cell adhesion are one of the most important characteristics of malignancy. Determination of replication-dependent histone H3 can be applied as a proliferative marker. Cyclin D1 (CCND1) regulates the cell cycle by participating in the control of the G1/S phase transition. Claudins (CLDN) are components of tight junctions and may play an essential role in the loss of tissue cohesion. The aim of the study was to assess the mRNA expression of histone H3, cyclin D1, and claudin 7 genes in laryngeal squamous cell carcinoma (LSCC) and adjacent nonneoplastic tissues. The study group consisted of 32 patients with LSCC. Adjacent nonneoplastic tissues of incision lines were used as controls. Quantification of H3, CCND1 and CLDN7 mRNAs was performed by the use of real-time QRT-PCR assay. Molecular analysis showed a significantly higher expression of CCND1 (P = 0.0001; Wilcoxon test) and H3 (P = 0.0141) genes in tumor tissues than in surrounding nonneoplastic tissues. On the contrary, transcriptional activity of claudin 7 gene was higher in histologically normal tissues; however, this difference was not statistically significant (P = 0.1499). The data obtained indicate that laryngeal cancer is characterized by high proliferative potential mediated by increase in cyclin D1 and H3 mRNAs expression.

Arsenic trioxide induced the apoptosis of laryngeal cancer via down-regulation of survivin mRNA

OBJECTIVE

Arsenic trioxide (As(2)O(3)) is used clinically to treat acute promyelocytic leukemia and has activity in vitro against several solid tumor cell lines, where induction of differentiation and apoptosis are the prime effects. As a novel anticancer agent for treatment of solid cancers, As(2)O(3) is promising and the mechanism has been not still fully understood. Laryngeal squamous cell carcinoma (LSCC) is one common tumor in head and neck cancers. The objective of this study was to investigate the effects of As(2)O(3) on LSCC cell line HEP-2, and their possible involvement in As(2)O(3)-induced apoptosis.

METHODS

The cell viability was analyzed by MTT assay method and the morphological changes were observed by an inverted microscope and acridine orange (AO) staining. The caspase-3 activity was measured by a fluorophotometer. The expression of survivin mRNA was evaluated by RT-PCR.

RESULTS

In this study, we demonstrated an apoptotic effect of As(2)O(3) in LSCC cell line Hep-2. In Hep-2 cells, As(2)O(3) decreased the cell viability, inhibited the growth and proliferation, induced apoptosis and increased the activity of caspase-3 in a dose-dependent manner. And the expression of survivin mRNA was also decreased in a dose-dependent manner.

CONCLUSION

We concluded that As(2)O(3) induced the apoptosis of Hep-2 cells via down-regulating the expression of survivin mRNA.

Loss of p21 expression is associated with p53 mutations and increased cell proliferation and p27 expression is associated with apoptosis in maxillary sinus squamous cell carcinoma

CONCLUSIONS

Loss of p21 expression dependent on the p53 mutation may be associated with higher tumor cell proliferation, and low p27 expression may be associated with decreased spontaneous apoptosis, resulting in poorer prognosis in patients with maxillary sinus squamous cell carcinoma (SCC).

OBJECTIVE

We have previously reported that p53 mutations and decreased spontaneous apoptosis were associated with poor prognosis in maxillary sinus SCC. However, whether p21 and p27 expression and cell proliferation correlate with either p53 status, spontaneous apoptosis or prognosis in maxillary sinus SCC has not been evaluated.

MATERIAL AND METHODS

Seventy patients with maxillary sinus SCC were analyzed. Tumor biopsy specimens were examined for p21 and p27 expression using an immunohistological method. The percentage of proliferating cells labeled by anti-Ki-67 mAb was expressed as the Ki-67 index (KI).

RESULTS

Loss of p21 expression correlated with p53 mutations (p=0.0072). The KIs in patients without p21 expression and with p53 mutations were significantly higher than those in patients with p21 expression (p=0.0119) and those without p53 mutations (p=0.0048). Patients with p27 expression showed a significantly higher apoptotic index than those without (p=0.0012). Kaplan-Meier analysis showed that p21 expression was closely associated with prolonged disease-free survival in the group with a normal p53 status (p=0.0472). Multivariate analysis identified high KI as an independent prognostic marker (p=0.047).

Expression of Cell Proliferation and Apoptosis Markers in Papillomas and Cancers of Conjunctiva and Eyelid

Cell proliferation and programmed cell death are considered to be important events in carcinogenesis. The object of our study was to evaluate the expression of the Bcl-2 protein family (Bcl-2, Bak, Bax), p53, proliferating cell nuclear antigen (PCNA), and Ki-67 protein immunoexpression as well as the correlation between the examined markers and some clinicopathological features in papillomas and cancers of conjunctiva and eyelid. Forty-five squamous cell papillomas (SCP), 11 squamous cell cancers (SCC), and 27 basal cell cancers (BCC) were estimated. In the SCP group, p53 protein expression was observed in 30 cases (66.6%), Ki-67 in 14 (31.1%), PCNA in 44 (97.8%), Bcl-2 in 24 (53.3%), Bak in 28 (62.2%), Bax in 31 (68.9%), and Bcl-xl in 11 (100%). In the SCC group, p53 protein expression was evaluated in 8 cases (72.8%), Ki-67 in 2 (18.2%), PCNA in 8 (72.7%), Bcl-2 in 5 (45.4%), Bax and Bak both in 10 (90.9%), and Bcl-xl in 100%. In the BCC group, p53 protein expression was estimated in 23 cases (85.1%), Ki-67 in 13 (48.1%), PCNA in 26 (96.2%), Bcl-2 in 13 (48.1%), Bak in 21 (77.8%), Bax in 22 (81.5%), and Bcl-xl in 23 (85.2%). We observed a correlation between some clinicopathological features and the examined markers of apoptosis and cell proliferation, which seemed to be important events in cancer development.

Immunohistological comparison of the World Health Organization (WHO) and Ljubljana classifications on the grading of preneoplastic lesions of the larynx

There is still controversy about the classification of laryngeal preneoplastic lesions. In this study, we compared the World Health Organization (WHO) and Ljubljana histological classifications with regard to laryngeal epithelial hyperplastic-dysplastic lesions in a single series to determine their relation to statistically significant criteria when the mechanisms of neoplastic progression are considered. Emphasis was put on p53 expression, proliferative activity, and angiogenesis. Fifty-four laryngeal biopsies with preneoplastic changes were re-evaluated and classified according to both classifications. The streptavidin-biotin method was used for immunohistochemical staining for Ki-67, p53, and CD34 antibodies. A positive correlation was obtained between the histological categories and Ki-67, p53, and CD34 expressions using both classifications (Spearman's Correlation test). There was a significant difference between the histological categories of both the WHO and the Ljubljana classifications, when the expression of the three markers was compared (Kruskal Wallis test, p = 0.000 for each). Further evaluation revealed a statistically significant difference between all categories of both classifications, excluding the p53 overexpression scores and vessel counts in mild and moderate dysplasia categories (Mann-Whitney U-test, p = 0.209, and 0.091 respectively), and the p53 overexpression scores in severe dysplasia and carcinoma in situ categories (Mann-Whitney U-test, p = 0.249) of the WHO classification. Similarly, no significant differences were found between severe dysplasia and carcinoma in situ, as well as between atypical hyperplasia and carcinoma in situ categories using both classifications for the Ki-67 expression (Mann-Whitney U-test, p = 0.806, and 0.111, respectively). Our results suggest that regarding the mechanisms of neoplastic progression such as p53 expression and angiogenesis, the histological categories of the Ljubljana classification seem to depend on additional evidence. Therefore, we support the use of the Ljubljana classification.

Immunohistochemical analysis of pro- and active-caspase 3 in laryngeal squamous cell carcinoma

Active caspase 3 is considered to be the main executioner caspase in apoptotic process. The mechanisms of apoptosis in laryngeal squamous cell carcinoma (LSCC) have been investigated by examining the expression profiles of pro-caspase 3 and active-caspase 3. The correlation between the two forms of caspase 3 and the p53 status was also determined. LSCCs ( n=65) were studied using immunohistochemistry with antibodies to pro-caspase 3, active-caspase 3 and p53. The expression of pro-caspase 3 was absent or weak in 16 (24.6%), moderate in 21 (32.3%) and strong in 28 (43.1%) cases. Survival curves for different levels of pro-caspase 3 differed, but the differences were not statistically significant. An apoptotic index (AI) was determined by quantifying the active-caspase 3-positive cells. The AI ranged from 0.2% to 9.4% and did not differ among the different levels of pro-caspase 3 expression. Even in cases in which the expression of pro-caspase 3 was considered negative, caspase 3-positive apoptotic cells were found. The AIs were significantly higher in supraglottic tumours compared with glottic counterparts ( P=0.008) and were higher in poorly differentiated tumours compared with well-differentiated and moderately differentiated LSCC ( P=0.06). No correlation between AI and p53 expression was found, although pro-caspase 3 expression trended to be higher in the p53-positive group of LSCC. Our results suggest that the expression of pro-caspase 3, a key executioner caspase in apoptosis, is downregulated in a proportion of LSCC, but this is not associated with decreased apoptotic activity, measured by active-caspase 3 labelling.

Automated image analysis of proliferating cells in carcinoma of the larynx

OBJECTIVE

To determine the role of cell proliferation neoplastic progression in the larynx and possibly derive criteria of clinical significance using automated quantitative image analysis.

MATERIAL AND METHODS

In a retrospective study involving archival material, the occurrence and location, size, shape and staining intensity of proliferating cell nuclear antigen (PCNA)-positive cells (12,538 cells in total) were analyzed in squamous cell carcinoma (SCC), as well as in pre- and non-neoplastic conditions, using computer-assisted morphometry with reproducibility and sensitivity exceeding 99%.

RESULTS

Immunohistochemically detectable PCNA-positive cells were located in the basal layer in non-neoplastic states, in well-differentiated SCCs in layers adjacent to the basal membrane and in poorly differentiated neoplasms in the neoplastic epithelial islets. An increased degree of dysplasia was associated with an increased number of PCNA-immunoreactive cells of increased nuclear size and staining intensity. There was a significant difference between carcinomas and dysplasia in terms of altered nuclear shape. With increasing malignancy of SCCs, nuclear shape alterations and PCNA staining intensity increased, whilst nuclear size decreased.

CONCLUSIONS

Automated image analysis of cell populations allowed the identification of populations of malignant cells and provided information on the severity of preneoplastic and neoplastic conditions of use in studies of tumor behavior and with potential clinical application.

Prognostic value of p53 mutations, bax, and spontaneous apoptosis in maxillary sinus squamous cell carcinoma

BACKGROUND

Many researchers have attempted to correlate p53 mutation and spontaneous apoptosis with the effectiveness of radiochemotherapy and with prognosis in several malignancies.

METHODS

The current study group consisted of 70 Japanese patients with maxillary sinus squamous cell carcinoma (SCC). Fifty seven patients were treated with radiochemotherapy followed by total or partial maxillectomy, and the remaining 13 patients were treated with radiotherapy alone. Tumor biopsy specimens at pretreatment status were examined for apoptosis-related proteins such as p53 protein, Fas, bax, bcl-x, and apoptosis using immunohistologic methods. The proportion of apoptotic cells labeled by single stranded DNA antibody was expressed as an apoptotic index (AI). p53 mutations at exons 5 through 8 were analyzed by direct sequence on polymerase chain reaction amplified products obtained from laser microdissected tissues. The effectiveness of radiochemotherapy was investigated histologically on surgically dissected specimens.

RESULTS

p53 mutations were identified in 20 (29%) of 70 patients. p53 protein was overexpressed in 39 patients (56%), Fas in 20 patients (29%), bax in 40 patients (57%), and bcl-x in 33 patients (47%). Overexpression of bax was associated with negativity of bcl-x (P = 0.015) and with high AI (P = 0.024). Low AI and/or p53 mutation in the pretreatment tissues correlated with low histologic effectiveness of radiochemotherapy (P = 0.048, P = 0.019, respectively). Kaplan-Meier analysis as well as univariate analysis using the Cox proportional hazards model showed that low histologic effectiveness of radiochemotherapy (P = 0.0281, P = 0.0284, respectively), p53 mutations (P = 0.0095, P = 0.0187, respectively), negativity of bax (P = 0.0069, P = 0.0191, respectively), and low AI (P = 0.0134, P = 0.0407, respectively) were significantly related to worse disease-free survival. Multivariate analysis showed AI as an independent factor predicting for disease-free survival (P = 0.0455).

CONCLUSIONS

The p53 mutations, expression of bax, and levels of spontaneous apoptosis have prognostic value in maxillary sinus SCC; AI especially is an independent factor for disease-free survival. A high level of spontaneous apoptosis induced by overexpression of bax may increase sensitivity of radiochemotherapy resulting in good prognosis, while p53 mutation may lead to resistance against radiochemotherapy, resulting in poor prognosis.

Expression of Bax and apoptosis-related proteins in human esophageal squamous cell carcinoma including dysplasia

The rate of tumor growth depends on the balance between proliferation and death of tumor cells. It is known that Bax, caspase-3, and p53 proteins are death-promoting factors, whereas Bcl-2 protein is a death antagonist. We immunohistochemically examined the expression of Bax and apoptosis-related proteins such as caspase-3, p53, and Bcl-2 in 76 patients with human esophageal squamous cell carcinoma (SCC) including dysplasia to determine the relationship of expression of each protein to tumor behavior and patients' prognosis. No significant relationships in immunopositivity were found among these proteins in SCCs. Cytoplasmic Bax expression was exhibited in 63 cases of SCCs (82.9%). The apoptotic index of caspase-3-positive lesions was significantly higher than that of caspase-3-negative lesions in both dysplasia and SCC (P =.016, P =.012). On the other hand, the apoptotic index (1.18%) was significantly correlated with Bax overexpression in dysplasia (P =.006), but not in SCC lesions (P =.129). The patients with Bax-positive SCCs were found to have a poor prognosis by the Kaplan-Meier method (P =.043). These findings suggested that Bax expressed in dysplasia may play a role as an apoptotic factor, but that it may be functionally inactive in some cancerous lesions and thus not contribute to suppression of the tumor progression in some cases of human esophageal SCCs.

Apoptosis, angiogenesis and proliferation: trifunctional measure of tumour response to radiotherapy for oral cancer

Local recurrence is a significant problem following radiotherapy in oral carcinoma and hence there is a paramount need for predictive markers. This study therefore analysed the predictive value of pre-treatment status of angiogenesis, apoptosis, expression of apoptosis regulatory p53, bax and bcl-2 proteins as well as tissue proliferation in relation to tumour response to radiotherapy. Sixty-nine histologically defined invasive carcinoma lesions were included in the study. Extent of apoptosis was defined morphologically and by the TUNEL (Tdt-mediated dUTP biotin nick end labelling) assay. Expression of apoptosis regulatory p53, bax and bcl-2 proteins were evaluated by immunocytochemistry. Mutant p53 protein was detected using a mutant p53-specific ELISA. The extent of tissue proliferation was evaluated by cyclin D1 expression. Angiogenesis was evaluated by CD34 antigen expression. All patients were treated with radical radiotherapy and followed up for 36 months. High levels of p53 protein detected by immunocytochemistry were found to be associated with poor response to treatment or disease relapse. Detection of mutant p53 protein also showed significant association with poor prognosis. Low levels of angiogenesis had a correlation with recurrence status. Tumours showing less vascularisation as well as increased apoptosis had a poor prognosis. Expression of p53 and bcl-2 proteins showed direct correlation with angiogenesis. There was no correlation between clinical status and any of the experimental parameters with histopathological grades of invasive lesions. Presence of mutant p53 protein is suggestive of poor tumour response to radiotherapy. Expression of p53 and increased apoptosis in less vascularised tumours is associated with treatment resistance. A predictive assay based on these results designed to analyse individual tumour samples showed presence of apoptotic cells near the vasculature to be indicative of good prognosis, while absence of apoptotic cells or highly proliferative cells and/or expression of bcl-2 protein in cells around the vasculature to be an indicator of poor prognosis.

Correlation of tumor markers p53, bcl-2 and cathepsin-D with clinicopathologic features and disease-free survival in laryngeal squamous cell carcinoma

Various recognized prognostic factors in squamous cell carcinoma (SCC) of the larynx influence the therapeutic options offered to an individual patient in order to extend the survival expectancy. Additional prognostic indicators are required in specific patient subgroups. The present study used a standard immunohistochemical technique in order to retrospectively evaluate the accumulation of p53 gene product and the immunoreactivity of bcl-2 protein and cathepsin-D as possible prognostic markers of laryngeal SCC. Formalin-fixed, paraffin-embedded tumor materials were obtained from a series of 64 patients with cancer of the larynx. Immunostaining was evaluated by computerized image analysis. The accumulation of p53 protein was found in 57.8% (37/64) of the patients and was associated with large tumor size. The percentage of p53-positive neoplastic cells increased in high-grade carcinomas, particularly when they simultaneously demonstrated cathepsin-D immunoreaction in stromal cells (P = 0.049); bcl-2 immunoexpression was found to be generally limited. Cathepsin-D immunostaining was observed in tumor parenchymal and stromal cells (31.25% and 37.5% of all cases, respectively); it was found to be useful in defining patient subgroups with differences in relapse-free survival. Among patients with posi-tive lymph nodes, those with cathepsin-D immunopositive tumor cells were at higher risk for relapsing (P = 0.0395). Although the classical prognostic factors of laryngeal carcinoma retain their predominance, cathepsin-D immunoreactivity may serve as an additional prognosticator in specific patient subgroups.