Non-neoplastic Squamous Epithelium Research Articles

TRPS1 expression is sensitive and specific for primary extramammary Paget disease.

Extramammary Paget disease (EMPD) is an epithelial neoplasm that can occur at many sites, including the vulva and scrotum. EMPD is characterised by the presence of neoplastic cells, in single cells and clusters, that infiltrate all layers of non-neoplastic squamous epithelium. The differential diagnosis for EMPD includes melanoma in situ and secondary involvement of tumours from other sites, such as urothelial or cervical; pagetoid spread of tumor cells can also been seen at other sites, such as anorectal mucosa. The most frequently utilised biomarkers for confirming the diagnosis of EMPD include CK7 and GATA3; however, these biomarkers lack specificity. The purpose of this study was to evaluate TRPS1, a newly described breast biomarker, in pagetoid neoplasms of the vulva, scrotum and anorectum. Fifteen cases of primary EMPD of the vulva (two with associated invasive carcinoma) and four primary EMPD of the scrotum showed strong nuclear immunoreactivity for TRPS1. In contrast, five cases of vulvar melanoma in situ, one case of urothelial carcinoma with secondary pagetoid spread into the vulva and two anorectal adenocarcinomas with pagetoid spread into anal skin (one with associated invasive carcinoma) were negative for TRPS1. Additionally, weak nuclear TRPS1 staining was observed in non-neoplastic tissues (e.g. keratinocytes), but always with less intensity when compared to tumour cells. These results demonstrate that TRPS1 is a sensitive and specific biomarker for EMPD, and may be especially useful for excluding secondary involvement of the vulva by urothelial and anorectal carcinomas.

The Histopathological Study of Gastrointestinal Polyps

Polyps covered by non-neoplastic squamous epithelium may develop anywhere in the esophagus. Squamous polyps may be divided in to two types: Inflammatory polyps and squamous papillomas. To study the incidence and morphology of Gastro Intestinal Tract polyps from specimens received at Sree Balaji Medical College and Hospital, Chennai. To analyze the incidence and morphological features of malignancies associated with polyps. Of the 102 cases, intestinal cancer was found predominately 51(50%) followed by stomach. The ages ranged from 17 to 77 yrs and average was 44 yrs. The female ratio was 0.77. Expression of P53 was varied with the property of the polyps and it could be a useful marker for determining the treatment regime.

Roles of the hexosamine biosynthetic pathway and pentose phosphate pathway in bile acid-induced cancer development.

Esophageal squamous cell carcinomas (ESCCs) as well as adenocarcinomas (EACs) were developed in rat duodenal contents reflux models (reflux model). The present study aimed to shed light on the mechanism by which bile acid stimulation causes cancer onset and progression. Metabolomics analyses were performed on samples of neoplastic and nonneoplastic tissues from reflux models, and K14D, cultivated from a nonmetastatic, primary ESCC, and ESCC‐DR, established from a metastatic thoracic lesion. ESCC‐DRtca2M was prepared by treating ESCC‐DR cells with taurocholic acid (TCA) to accelerate cancer progression. The lines were subjected to comprehensive genomic analyses. In addition, protein expression levels of glucose‐6‐phosphate dehydrogenase (G6PD), nuclear factor kappa B (NF‐κB) (p65) and O‐linked N‐Acetylglucosamine (O‐GlcNAc) were compared among lines. Cancers developed in the reflux models exhibited greater hexosamine biosynthesis pathway (HBP) activation compared with the nonneoplastic tissues. Expression of O‐GlcNAc transferase (OGT) increased considerably in both ESCC and EAC compared with nonneoplastic squamous epithelium. Conversely, cell line‐based experiments revealed the greater activation of the pentose phosphate pathway (PPP) at higher degrees of malignancy. G6PD overexpression in response to TCA exposure was observed. Both NF‐κB (p65) and O‐GlcNAc were expressed more highly in ESCC‐DRtca2M than in the other cell lines. Moreover, ESCC‐DRtca2M cells had additional chromosomal abnormalities in excess of ESCC‐DR cells. Overall, glucose metabolism was upregulated in both esophageal cancer tissue and cell lines. While bile acids are not mutagenic, chronic exposure seems to trigger NF‐κB(p65) activation, potentially inducing genetic mutations as well as facilitating carcinogenesis and cancer progression. Glucose metabolism was upregulated in both esophageal cancer tissue and cell lines, and the HBP was activated in the former. The cell line‐based experiments demonstrated upregulation of the pentose phosphate pathway (PPP) at higher degrees of malignancy. While bile acids are not mutagenic, chronic exposure seems to trigger G6PD overexpression and NF‐κB (p65) activation, potentially inducing genetic mutations as well as facilitating carcinogenesis and cancer progression.

PS02.025: CHARACTERISTICS OF SUPERFICIAL BASALOID SQUAMOUS CELL CARCINOMA TREATED BY ENDOSCOPIC RESECTION

Abstract Background Basaloid squamous cell carcinoma (BSCC) is a rare esophageal carcinoma. And the characteristics especially in early stage is unknown. Methods The aim of this study is to clarify the characteristics of superficial BSCC. Thirteen patients (9 males and 4 females) with BSCC treated by endoscopic resection (12 ESD and 1 EMRC) from January 2000 to March 2017 were enrolled in this retrospective study. The median age was 67 (57–83). The median follow-up period was 24 (12–115) months. T1a-EP/LPM and T1a-MM/T1b-SM1 without lymph duct invasion (LDI) was followed up. T1a-MM/T1b-SM1 with LDI or T1b-SM2 were treated by additional treatment (AT). Results 1. En-bloc resection and R0 resection rate was 100% and 100%, respectively. 2. Macroscopic type; 0-IIa, 0-IIb and 0-IIc was 4, 1 and 8, respectively. 3. The median tumor diameter was 27 (2–62) mm. 4. Invasion depth; T1a-LPM, T1a-MM/T1b-SM1, and T1b-SM2 was 3, 5 and 5, respectively. 5. Histological characteristics; All BSCC were covered by SCC or non-neoplastic squamous epithelium. 6. Endoscopic characteristics; SMT like appearance was found in 46% (6/13). Yellowish nodules were observed in 23% (3/13). This finding was observed, when BSCC exist superficial epithelial layer covered by thin non-neoplastic epithelium. 7. Prognosis A: T1a-LPM (N = 3). Two patients are alive without recurrence, and 1 patient died of other disease. B: T1a-MM/SM1 (N = 5). Two of 3 patients without LDI were followed up and alive. Remaining one patient wanted to be treated by CRT, and alive. Two patients had LVI, however they were followed up without AT because of patient's hope. One is alive, and another died of other disease. C: T1b-SM2 (N = 5). Two and one patients were treated by surgery and chemotherapy, respectively, and alive without recurrence. Remaining two patients were followed up without AT. One of 2 patients are alive without recurrence. Another patient dead of other disease. Conclusion 1. All of BSCC were covered by SCC or non-neoplastic epithelium. 2. SMT like appearance and yellowish nodules under squamous cell epithelium were the characteristic endoscopic findings. 3. 40% of T1aMM/T1bSM1 had LDI. It's higher than that of SCC. Therefore, En-bloc resection is necessary for the detailed histological examination. Disclosure All authors have declared no conflicts of interest.

Evaluation of nuclear chromatin using grayscale intensity and thresholded percentage area in liquid-based cervical cytology.

Development of computerized image analysis techniques has opened up the possibility for the quantitative analysis of nuclear chromatin in pathology. We hypothesized that the features extracted from digital images could be used to determine specific cytomorphological findings for nuclear chromatin that may be applicable for establishing a medical diagnosis. Three parameters were evaluated from nuclear chromatin images obtained from the liquid-based cervical cytology samples of patients with biopsy-proven high-grade squamous intraepithelial lesion (HGSIL), and compared between non-neoplastic squamous epithelia and dysplastic epithelia groups: (1) standard deviation (SD) of the grayscale intensity; (2) difference between the maximum and minimum grayscale intensity (M-M); and (3) thresholded area percentage. Each parameter was evaluated at the mean, mean-1SD, and mean-2SD thresholding intensity levels. Between the mean and mean-1SD levels, the thresholded nuclear chromatin pattern was most similar to the chromatin granularity of the unthresholded grayscale images. The SD of the gray intensity and the thresholded area percentage differed significantly between the non-neoplastic squamous epithelia and dysplastic epithelia of HGSIL images at all three thresholding intensity levels (mean, mean-1SD, and mean-2SD). However, the M-M significantly differed between the two sample types for only two of the thresholding intensity levels (mean-1SD and mean-2SD). The digital parameters SD and M-M of the grayscale intensity, along with the thresholded area percentage could be useful in automated cytological evaluations. Further studies are needed to identify more valuable parameters for clinical application.

SIRT1 overexpression in cervical squamous intraepithelial lesions and invasive squamous cell carcinoma

Invasive squamous cell carcinoma (SCC) of the cervix involves the progression of premalignant cervical intraepithelial neoplasia (CIN) and is associated with persistent human papillomavirus infection. Most CINs will regress, and the challenge is to identify the lesions likely to progress to invasive cancer. We evaluated Sirtuin 1 (SIRT1) expression in nonneoplastic cervix, CINs, and SCCs as a potential biomarker to predict disease progression. A total of 101 cases were selected including 29 CIN 1s, 32 CIN 2s, 16 CIN 3s, 2 microinvasive SCCs, and 22 invasive SCCs. Cervical nonneoplastic squamous epithelium showed weak positivity of SIRT1 in the basal layer. SIRT1 cytoplasmic overexpression was found in 13.8% of CIN 1s (4/29), 40.6% of CIN 2s (13/32), and 50% of CIN 3s (8/16), and it was statistically significant between CIN 1 and CIN 2/3 lesions (P=.01). All 24 cases of invasive and microinvasive SCC showed SIRT1 overexpression, with 25% (6/24) showing cytoplasmic staining only, 4.2% (1/24) showing nuclear staining only, and 70.8% (17/24) showing both nuclear and cytoplasmic staining. From CIN 1 to SCC, SIRT1 expression showed steady and statistically significant increase (CIN 1 versus CIN 2-3, P=.01; CIN 2-3 versus SCC, P=.0001). Thus, SIRT1 may serve as a potential biomarker for predicting the progression of CIN to invasive SCC.

GLUT-1 expression is largely unrelated to both hypoxia and the Warburg phenotype in squamous cell carcinomas of the vulva.

BackgroundStrongly increased uptake of glucose is a hallmark of solid malignant tumors. This phenotype can be triggered by hypoxia-induced gene expression changes or can occur independently of hypoxia as a consequence of malignant transformation itself, and is often referred to as the Warburg effect. The glycolytic phenotype has been associated with malignant progression and resistance to radio- and chemotherapy.MethodsWe have chosen squamous cell carcinomas of the vulva (SCC-V) as a representative solid tumor entity to study the central players of this pathway, namely glucose transporter (GLUT)-1, carbonic anhydrase (CA) IX, hexokinase (HK)-2 and pyruvate kinase (PK)-M2, and have investigated their relationships to tumor microvessels (CD34, αSMA) and proliferation (Ki67). Expression of these proteins was analyzed in 38 SCC-Vs, 5 vulvar dysplasias and 10 non-neoplastic squamous epithelia of the vulva using multiparametric immunohistochemistry in registered serial sections (MIRSS).ResultsExpression of GLUT-1 in invasive carcinomas was predominantly located in the outer layers of the tumor cell aggregates close to the vascularized tumor stroma, and only to a lesser extent colocalized with CA IX, which was repeatedly found at larger diffusion distances away from microvessels. CA IX expression was lower in invasive carcinomas compared to dysplasias and non-neoplastic tissue and higher in recurrent vs. primary tumors. Ki67-positive proliferating cells were partially colocalized with GLUT-1. However, HK-2 and PK-2 - proteins centrally involved in the Warburg phenotype - did not show such a correlation.ConclusionsConsistent with prior studies, the pattern of GLUT-1 clearly indicated that a large part of its expression is presumably unrelated to hypoxia. However, there was also no association with HK-2 and PK-M2, suggesting that the functional background of this expression is also independent of aerobic glycolysis. CA IX may be worth consideration as a marker of biological hypoxia, as should its pathophysiological consequences in SCC-V.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2407-14-760) contains supplementary material, which is available to authorized users.

Expression of Ep‐CAM, but not of E48, associates with nodal involvement in advanced squamous cell carcinomas of the larynx

To evaluate epithelial cell adhesion molecule (Ep-CAM) and E48 expression, and their relationship with histological differentiation and nodal metastasis, in laryngeal squamous cell carcinomas (SCC). The expression of Ep-CAM and E48 was investigated using immunohistochemistry in a series of 66 SCC (stages 3 and 4) and their adjacent non-neoplastic epithelia. Ep-CAM expression increased with the progression from normal squamous epithelium to SCC. It was detected in 96% of carcinomas and high levels of Ep-CAM expression (50% or more positive cells) were associated with poorer differentiation (P = 0.003) and the presence of lymph node metastases (P = 0.001). E48 expression was characteristically strong and diffuse in non-neoplastic squamous epithelium, and decreased with progression to SCC. Poorly differentiated (grade 4) tumours had lower proportions of E48-positive cells than well- to moderately- differentiated cases (P < 0.001). Expression of both Ep-CAM and E48 correlated with cell differentiation, although in inverse fashion. In particular, the association between high levels of Ep-CAM expression and high frequency of nodal metastases suggests that Ep-CAM plays a role in the development of lymph node metastases in SCC of the larynx.

Expression of Human Telomerase Reverse Transcriptase in Vulvar Intraepithelial Neoplasia and Squamous Cell Carcinoma: An Immunohistochemical Study With Survivin and p53

Human telomerase reverse transcriptase (hTERT), an enzyme that enables cells to overcome replicative senescence and to divide indefinitely, is overexpressed in many cancers and their precursor lesions. To test whether hTERT expression is related to neoplastic progression and resistance to apoptosis in vulvar epithelia. Immunoexpression of hTERT was evaluated in 101 formalin-fixed, paraffin-embedded archival vulvar epithelia consisting of normal squamous vulvar epithelia (n = 25), lichen sclerosus (n = 10), high-grade classic vulvar intraepithelial neoplasia (n = 16), differentiated vulvar intraepithelial neoplasia (n = 18), and vulvar invasive keratinizing squamous cell carcinoma (n = 32) and related to survivin and p53 expression. Immunostaining for all factors was scored for moderate and strong intensities with regard to quantity to determine upregulation and overexpression (score 0, 0% immunoreactive cells; score 1+, <5% immunoreactive cells; score 2+, 5% to 50% immunoreactive cells; score 3+, >50% immunoreactive cells). Score 3+ was considered as overexpression. Nuclear hTERT immunoexpression was closely related to survivin reactivity, increased from normal vulvar squamous epithelia to lichen sclerosus and to high-grade classic vulvar intraepithelial neoplasia, differentiated vulvar intraepithelial neoplasia, and invasive keratinizing squamous cell carcinoma (P < .001), and followed the morphologic distribution of atypical squamous epithelial cells. Overexpression of hTERT was comparable to that seen for p53 in invasive keratinizing squamous cell carcinoma (P = .62); significant differences were calculated for differentiated vulvar intraepithelial neoplasia (P = .003) and high-grade classic vulvar intraepithelial neoplasia (P = .001). Human telomerase reverse transcriptase is upregulated in vulvar intraepithelial neoplasia and invasive keratinizing squamous cell carcinoma compared with nonneoplastic squamous epithelia of the vulva as an apparently early and preinvasive event in the neoplastic transformation, with development of cellular longevity and resistance to apoptosis by survivin activation as associated features, independent of the etiology of vulvar intraepithelial neoplasia.

Anal duct carcinoma: a report of 5 cases

Anal duct carcinoma (ADC) is a rare lesion composed of glands undermining non-neoplastic squamous epithelium. We describe the clinicopathologic characteristics and follow-up of 5 cases of ADC. Four definitive cases had tissue available for immunohistochemistry (IHC; CK7, CK20, prostate-specific antigen [PSA], estrogen/progesterone receptors [ER/PR], and p16) and in situ hybridization (ISH) for high-risk human papillomavirus (HR-HPV); a fifth case, with a history of ADC, had limited tissue for immunolabeling with only CK7, CK20, and p16. The mean patient age was 69.8 years. All 5 cases were CK7-positive and p16-negative. Four of 5 cases were CK20-negative. All cases with sufficient tissue (4/4) were negative for HR-HPV by ISH, PSA-negative (men), and ER/PR-negative (women). Four of 5 patients had previous malignancies, and in all 4 cases with sufficient tissue, metastasis was excluded with IHC. Of 5 patients, 3 developed metastases, whereas 2 had isolated local recurrences. ADCs are neoplasms with metastatic potential and can result in poor outcomes.

Anal duct carcinoma in a 70-year-old male with a history of prostate cancer

Anal duct (gland) carcinoma is a rare, under-recognized neoplasm of the anal canal. Histologically, it consists of haphazardly oriented neoplastic glands that proliferate beneath intact non-neoplastic squamous epithelium. Frequently, Pagetoid-like spread into the overlying squamous epithelium may be observed. Anal duct carcinoma is characteristically CK7+/CK20− by immunohistochemistry. We report a case of anal duct carcinoma diagnosed in a 70-year-old male with a history of treated prostate cancer. The epidemiology, clinical presentation, histologic features, differential diagnosis, treatment, and prognosis of anal duct carcinoma are discussed.

N-cadherin expression is correlated with metastasis of spindle cell carcinoma of head and neck region

Spindle cell carcinoma (SpCC) is a biphasic tumor composed of conventional squamous cell carcinoma and a malignant spindle cell component. SpCC expresses both epithelial and mesenchymal markers by immunohistochemical analysis. There is mounting evidence for sarcomatoid transformation from the epithelial component, supporting the theory that SpCC is a monoclonal neoplasm originating from a stem cell giving rise to both components. The loss of E-cadherin and the gain of N-cadherin expression are known as the "cadherin switching". Cadherin switching is a major hallmark of epithelial-mesenchymal transition (EMT). EMT is a crucial process in cancer progression providing cancer cells with the ability to escape from the primary focus, to invade stromal tissues, and to migrate to distant regions. Although E-cadherin down-regulation is well known in various cancers, there are a few studies on N-cadherin expression in cancer. Here, therefore, we investigated N-cadherin expression in the progression of head and neck SpCC. First, we examined cadherin switching in our established SpCC cell lines, SpCC-1 and SpCC-2. SpCC-1 and SpCC-2 cells were spindle in shape and showed cadherin switching. Moreover, we examined N-cadherin expression in 15 SpCC cases by immunohistochemistry. Although N-cadherin expression was not observed in non-neoplastic squamous epithelium, high expression of N-cadherin was observed in 10 of 15 SpCC cases. Interestingly, 6 of 7 SpCC cases with metastasis showed high expression of N-cadherin. In conclusion, our findings suggest that N-cadherin may play an important role in metastasis of SpCC in addition to the pathogenesis of SpCC of the head and neck.

Novel Histochemical Stain for Tinctorial Detection of Cancer and Neoplastic Cells

Zetiq has introduced a histochemical stain that claims to tinctorially identify cancer and neoplastic cells. Because of the potential importance of such a capability, we undertook to investigate Zetiq's CellDetect® staining technology as applied to cultured cell lines as well as an initial sample of clinical cases. This goal was pursued by investigating four types of comparisons: 1) cancer cell lines before and after differentiation; 2) cervical squamous-cell carcinoma (SCC) biopsies to non-neoplastic squamous epithelium; 3) SCCs to neoplastic, nonmalignant squamous epithelium; and 4) neo-plastic squamous cells to non-neoplastic squamous cells in cytological preparations. The clinical material was also stained with hematoxylin and eosin (biopsies) or Pap (cytologies) for diagnostic purposes. We found that all CellDetect®-stained cells exhibited one of the two tinctorial outcomes. Cell lines with malignant phenotype uniformly had red/purple cytoplasm, whereas the differentiated phenotype changed the color to blue/green. Moreover, these two color values are sufficiently distinct that they can be readily distinguished quantitatively with an ELISA reader when applied to cells in tissue culture. Biopsies of SCC and non-neoplastic tissues exhibit the same two color values: cancers had red/purple cytoplasm, whereas non-neoplastic tissues were green/blue stained. In contrast, neoplastic, nonmalignant tissues (dysplasias) stained red/purple, similar to SCCs. Cytological preparations gave similar results: neoplastic cells stained red/purple, whereas non-neoplastic cells exhibited green/blue cytoplasm. The study demonstrated that the staining was rapid and reproducible. Conclusion: The CellDetect® stain allows detecting cancer and neoplastic cells tinctorially based on a rapid, reproducible histochemical process.

Expression of complement restriction factors (CD46, CD55 &amp; CD59) in head and neck squamous cell carcinomas

Tumor cells can escape complement-dependent cytotoxicity (CDC) by expressing complement restriction factors (CRFs), CD46, CD55 and CD59. CRF-expression in non-neoplastic mucosa of the head and neck was compared with biopsies of the head and neck squamous cell carcinoma (HNSCC) and cell lines derived from oral squamous cell carcinomas (OSCC). Normal mucosa and HNSCC tumor tissue (poor, moderate, or well differentiated) specimens were immunostained with anti-CRF monoclonal antibodies. Immunostaining of the OSCC cell lines (SCC12 and SCC71) was examined under laser scan fluorescence microscopy. CD46, CD55 and CD59 were highly expressed in HNSCC cells including T1/T2N0M0 stages. The CRF expression was much lower or absent in non-neoplastic squamous epithelia or in the submucosa of both normal and tumor tissues. Enhanced staining of tumor tissues at stages T1/T2 indicates that the CRFs are overexpressed by primary tumors before metastasis to either lymph nodes or organs (N0M0 stage) suggesting that CRFs are formed early during tumorigenesis.

Expression of DNA damage response proteins and complete remission after radiotherapy of stage IB–IIA of cervical cancer

The primary aim of this study was to investigate if the expression of the DNA damage identifying protein DNA-PKcs known to be involved in DNA repair after treatment with ionising radiation can be used as a predictive marker for radiotherapy (RT) response in cervical cancer. Formalin-fixed primary tumour biopsies from 109 patients with cervical cancer, FIGO-stage IB–IIA, treated with preoperative brachytherapy followed by radical surgery were analysed by immunohistochemistry. In addition, correlation studies between early pathological tumour response to radiation and expression of Ku86, Ku70, Mdm-2, p53 and p21 in primary tumours were also performed. We found that tumour-transformed tissue shows positive immunostaining of DNA-PKcs, Ku86 and Ku70, while non-neoplastic squamous epithelium and tumour-free cervix glands show negative immunoreactivity. Expression of DNA-PKcs positively correlated with both Ku86 and Ku70, and a statistically significant correlation between the Ku subunits was also found. After RT, 85 patients demonstrated pathologic complete remission (pCR), whereas 24 patients had residual tumour in the surgical specimen (non-pCR). The main finding of our study is that there was no correlation between the outcome of RT and the expression of DNA-PK subunits. Positive p53 tumours were significantly more common among non-pCR cases than in patients with pCR (P=0.031). Expression of p21 and Mdm-2 did not correlate with the outcome of RT.

Immunohistochemical expression of DNA mismatch repair (MMR) system proteins (hMLH1, hMSH2) in cervical preinvasive and invasive lesions

The purpose of our study was to analyze the immunohistochemical expression of two MMR system proteins at different steps of neoplastic progression within the squamous cervical epithelium. We compared cases showing normal histologic appearance with those affected by low and high-grade squamous intraepithelial lesions and invasive cervical carcinoma. We investigated formalin-fixed and paraffin-embedded tissue specimens obtained from 83 selected patients (55 with preinvasive neoplastic lesions and 28 with invasive squamous cervical carcinoma) for the expression of hMSH2 and hMLH1 at the immunohistochemical level. We also included 30 patients with histologically normal cervix as a control group. Epithelial cells of CIN lesions showed a significant increase in the expression of both hMLH1 and hMSH2 proteins compared to non-neoplastic squamous epithelium ( p < 0.0001 ). The cases of invasive carcinoma showed a positivity for hMLH1 protein that was statistically lower than that for non-neoplastic cells ( p = 0.0009 ) and that for cases with CIN ( p < 0.0001 ). Positivity for hMSH2 protein was higher than that for normal epithelium ( p = 0.0007 ), but lower than that for preinvasive lesions ( p = 0.0001 ). Preinvasive lesions showed increased expression of both proteins if compared with normal esocervical epithelium. Neoplastic stromal invasiveness is associated with a significant loss of hMLH1 function.

Expression of p16, Rb, and p53 Proteins in Squamous Cell Carcinomas of the Anorectal Region Harboring Human Papillomavirus DNA

Human papillomavirus (HPV) has been implicated as an etiologic agent for the development of squamous cell carcinoma of the anorectal region. It has been shown that the HPV E6 and E7 oncoproteins are able to inactivate the tumor suppressor functions of p53 and Rb. In cervical and head and neck cancers, HPV infection is also associated with an overexpression of p16, a cyclin-dependent kinase inhibitor. The expression of these cell cycle regulators in squamous cell carcinomas of the anorectal region has not been well studied. In the current study, 29 cases of squamous cell carcinoma of the anorectal region were immunohistochemically examined for the expression of p16, Rb, and p53 proteins. Tumor cell DNA was also extracted from paraffin blocks and subjected to broad-spectrum HPV DNA testing and typing. The results show that the tumor cells exhibited a strong and diffuse nuclear stain (with some cytoplasmic positivity) for p16 in all 29 cases (100%). The adjacent nonneoplastic squamous epithelium or colonic mucosa, in contrast, was completely negative. Loss of Rb nuclear staining in tumor cells was observed in 20 cases (69%). The p53 protein was essentially undetectable, with only 6 cases containing <10% positive cells. HPV DNA was detected in every case (100%), with 25 cases (86%) harboring Type 16. In addition, almost identical results were obtained in 12 HPV-positive squamous cell carcinomas of the upper aerodigestive tract. This was in marked contrast to those of HPV-negative tumors, where positive p16 staining and loss of Rb expression were seen in only 2/21 (10%) and 1/21 (5%) cases, respectively. These observations indicate that overexpression of p16 and loss of Rb nuclear staining are commonly associated with high-risk HPV infection, which may serve as useful surrogate biomarkers for identifying squamous cell carcinomas harboring HPV DNA.

A CASE OF BRANCHIOGENIC CARCINOMA

A 53-year-old male was seen at the hospital because of a tumor on the right side of the neck. It was measured 4.5×3.8 cm in size and palpated in the anterior margin of the sternocleidomastoid muscle on the right side of the neck. CT scan revealed a cystic lesion with homogenous low density area, and the tumor was diagnosed as lateral cervical cyst. However, histologically, squamous cell carcinoma was found in the non-neoplastic squamous epithelium lining the cyst wall. Therefore, we definitely diagnosed it as branchiogenic carcinoma.

Expression of Cytokeratins in Squamous Cell Carcinomas of the Larynx: Immunohistochemical Analysis and Correlation with Prognostic Factors*

The expression of distinct cytokeratin subtypes in squamous cell carcinomas (SQCC) of the larynx was examined by immunohistochemistry with a panel of monoclonal antibodies (MABs) and different immunophenotypes were correlated with known prognostic factors, such as tumor site, local extension, degree of morphologic differentiation and lymph node metastasis. Among 50 cases of laryngeal SQCC tested, all 22 low grade tumors (Broders I and II) reacted strongly with MABs AE1, AE3 and KB.12, which corresponds to the phenotype of non-neoplastic squamous epithelium of the larynx. MABs K8.13 and K8.60 were negative only in 1 and 4 cases respectively. In these tumors CAM5.2 was either negative (18 cases) or weakly positive (4 cases). In contrast, we found that of 28 high grade SQCC (Broders III and IV) tested, strong reactivity with MABs AE1, AE3, K8.12 and K8.13 was restricted to smaller subsets, whereas CAM5.2 immunoreactivity was seen in 16 cases (57%). By morphological criteria 31 out of 50 cases in our series of SQCC showed keratinization and 30 of these 31 showed coexpression of cytokeratins identified by MABs AE3, K8.12, K8.13 and K8.60 and 29 cases by MAB AE1. The remaining non-keratinizing SQCC showed heterogeneous immunoreactivity for AE1, AE3 and K8.12 in 13 cases, for K8.13 in 12 cases and for K8.60 in 5 cases. Thirty of the 50 SQCC tested had no known lymph node metastasis and of these, 29 reacted with MABs AE1, AE3, K8.12 and K8.13 respectively, the remaining cases being either unreactive or only weakly reactive. Statistical analysis showed no significant differences between cytokeratins expression in SQCC and either anatomical location or local extension (pT).(ABSTRACT TRUNCATED AT 250 WORDS)