The Diagnostic Accuracy of Reverse Transcription-PCR Quantification of Cytokeratin mRNA in the Detection of Sentinel Lymph Node Invasion in Oral and Oropharyngeal Squamous Cell Carcinoma: A Comparison with Immunohistochemistry

Association between lymph node ratio and survival outcomes in patients with oral squamous cell carcinoma

BACKGROUND

Recent reports have shown that the Lymph node ratio (LNR) is useful for predicting the prognosis in some cancers, however there are few reports on the usefulness of LNR in predicting the prognosis of oral squamous cell carcinoma (OSCC). The predictive value of LNR for prognosis of OSCC was investigated.

MATERIALS AND METHODS

The study included 152 patients with OSCC and histologically confirmed cervical lymph node metastasis who underwent neck dissection. We analyzed the relationship between LNR and overall survival (OS) and recurrence-free survival (RFS) retrospectively in these cases, with the relationship between prognosis and clinicopathological findings also examined.

RESULTS

Using a receiver operating characteristics curve, the LNR cutoff value was set at 0.095, categorizing 64 and 88 cases into high LNR (≥ 0.095) and low LNR (< 0.095) groups, respectively. Regarding OS and RFS, the prognosis was significantly worse in the high LNR group compared with the low LNR group. In multivariate analysis, sex, postoperative nodal stage, and LNR merged as independent prognostic factors.

CONCLUSION

This study's findings suggest that LNR may represent a prognostic indicator in OSCC with cervical lymph node metastasis.

Utility of Keratins as Biomarkers for Human Oral Precancer and Cancer

Human oral cancer is the single largest group of malignancies in the Indian subcontinent and the sixth largest group of malignancies worldwide. Squamous cell carcinomas (SCC) are the most common epithelial malignancy of the oral cavity, constituting over 90% of oral cancers. About 90% of OSCCs arise from pre-existing, potentially malignant lesions. According to WHO, OSCC has a 5-year survival rate of 45–60%. Late diagnosis, recurrence, and regional or lymph nodal metastases could be the main causes of the high mortality rates. Biomarkers may help categorize and predict premalignant lesions as high risk of developing malignancy, local recurrence, and lymph nodal metastasis. However, at present, there is a dearth of such markers, and this is an area of ongoing research. Keratins (K) or cytokeratins are a group of intermediate filament proteins that show paired and differentiation dependent expression. Our laboratory and others have shown consistent alterations in the expression patterns of keratins in both oral precancerous lesions and tumors. The correlation of these changes with clinicopathological parameters has also been demonstrated. Furthermore, the functional significance of aberrant keratins 8/18 expression in the malignant transformation and progression of oral tumors has also been documented. This article reviews the literature that emphasizes the value of keratins as biomarkers for the prognostication of human oral precancers and cancers.

Equivalence Randomized Trial to Compare Treatment on the Basis of Sentinel Node Biopsy Versus Neck Node Dissection in Operable T1-T2N0 Oral and Oropharyngeal Cancer

PURPOSE

Sentinel node (SN) biopsy is accurate in operable oral and oropharyngeal cT1-T2N0 cancer (OC), but, to our knowledge, the oncologic equivalence of SN biopsy and neck lymph node dissection (ND; standard treatment) has never been evaluated.

METHODS

In this phase III multicenter trial, 307 patients with OC were randomly assigned to (1) the ND arm or (2) the SN arm (experimental arm: biopsy alone if negative, or followed by ND if positive, during primary tumor surgery). The primary outcome was neck node recurrence-free survival (RFS) at 2 years. Secondary outcomes were 5-year neck node RFS, 2- and 5-year disease-specific survival (DSS), and overall survival (OS). Other outcomes were hospital stay length, neck and shoulder morbidity, and number of physiotherapy prescriptions during the 2 years after surgery.

RESULTS

Data on 279 patients (139 ND and 140 SN) could be analyzed. Neck node RFS was 89.6% (95% CI, 0.83% to 0.94%) at 2 years in the ND arm and 90.7% (95% CI, 0.84% to 0.95%) in the SN arm, confirming the equivalence with P < .01. The 5-year RFS and the 2- and 5-year DSS and OS were not significantly different between arms. The median hospital stay length was 8 days in the ND arm and 7 days in the SN arm (P < .01). The functional outcomes were significantly worse in the ND arm until 6 months after surgery.

CONCLUSION

This study demonstrated the oncologic equivalence of the SN and ND approaches, with lower morbidity in the SN arm during the first 6 months after surgery, thus establishing SN as the standard of care in OC.

Essential gene expression pattern of head and neck squamous cell carcinoma revealed by tumor-specific expression rule based on single-cell RNA sequencing

Head and neck squamous cell carcinoma (HNSCC) has been widely reported and considered as one of the most threatening diseases to human health. Derived from complicated tissue subtypes, HNSCC has diverse symptoms and pathogenesis. They make the identification of the core carcinogenic factors of such diseases at the multi-cell level difficult. With the development of single-cell sequencing technologies, the effects of non-malignant cells on traditional bulk sequencing data can be eliminated directly. On the basis of fresh single-cell RNA-seq data, we set up a computational filtering strategy for tumor cell identification in an expression rule manner. This strategy can reveal the accurate expression distinction between tumor cells and adjacent tumor microenvironment, which are all supported by literature reports. Validated by several independent datasets, these rule genes can further group HNSCC patients with significant difference on survival risks. Thus, the establishment of our computational approach may not only provide an efficient tool to identify malignant cells in the tumor ecosystem but also deepen our understanding of tumor heterogeneity and tumorigenesis.

Immunohistochemical detection of lymph node-DTCs in patients with node-negative HNSCC

This study was performed to systematically assess the prevalence, topography and prognostic impact of disseminated tumor cells (DTCs) in lymph nodes (LN) of patients with primary, regional and distant metastasis-free head and neck squamous cell carcinoma (HNSCC) who underwent resection with elective neck dissection. From the routinely processed resection specimen, we could prospectively analyze a total of 1.137 exactly mapped LNs of 50 pN0-HNSCC patients, classified as tumor free by routine histopathology. Three immunohistochemistry (IHC) assays using antibodies directed against CK5/14, a broad spectrum of CKs (1-8, 10, 14-16 and 19), and CD44v6, respectively, were applied on 4.190 LN sections to detect DTCs. The IHC results were correlated with clinicopathologic parameters and clinical follow-up data. We detected seven micrometastases (MM) in five patients and 31 DTCs in 12 patients. Overall, 15 (30%) patients were positive for DTCs or MMs. Strikingly, the anatomical distribution of LN affected with DTCs was not random, but was dependent on the lateralization of the primary tumor and clustered significantly most proximal to the primary tumor. None of the investigated patients developed loco-regional lymphatic or distant metastasis during the mean follow-up period of 71 months. Our results reveal clinically occult tumor cell dissemination as an early and frequent event in HNSCC. Considering that higher rates of recurrences in therapeutic LN dissection concepts have been reported than in elective neck dissection strategies, our DTC-data support to perform elective neck dissections, since they appear to be effective in preventing loco-regional lymphatic recurrence from LN DTCs or MMs.

Intraoperative Sentinel Lymph Node Evaluation: Implications of Cytokeratin 19 Expression for the Adoption of OSNA in Oral Squamous Cell Carcinoma

BACKGROUND

Intraoperative analysis of sentinel lymph nodes would enhance the care of early-stage oral squamous cell carcinoma (OSCC). We determined the frequency and extent of cytokeratin 19 (CK19) expression in OSCC primary tumours and surrounding tissues to explore the feasibility of a "clinic-ready" intraoperative diagnostic test (one step nucleic acid amplification-OSNA, sysmex).

METHODS

Two cohorts were assembled: cohort 1, OSCC with stage and site that closely match cases suitable for sentinel lymph node biopsy (SLNB); cohort 2, HNSCC with sufficient fresh tumour tissue available for the OSNA assay (>50 mg). CK19 assays included qRT-PCR, RNA in situ hybridisation (ISH), and immunohistochemistry (IHC), as well as OSNA.

RESULTS

CK19 mRNA expression was detected with variable sensitivity, depending on method, in 60-80% of primary OSCC tumours, while protein expression was observed in only 50% of tumours. Discordance between different techniques indicated that OSNA was more sensitive than qRT-PCR or RNA-ISH, which in turn were more sensitive than IHC. OSNA results showed CK19 expression in 80% of primary cases, so if used for diagnosis of lymph node metastasis would lead to a false-negative result in 20% of patients with cervical lymph node metastases.

CONCLUSIONS

OSNA in its current form is not suitable for use in OSCC SLNB due to inadequate expression of the CK19 target in all case. However, the same assay technology would likely be very promising if applied using a more ubiquitous squamous epithelial target.

Oropharyngeal cancers: significance of HPV16 detection in neck lymph nodes

BACKGROUND

An increasing proportion of oropharyngeal squamous cell carcinomas (OPSCCs) is associated with human papillomavirus (HPV) type 16 infection. Several authors have suggested that HR-HPV DNA could be used as a marker of metastases in cervical cancers. Although HPV16 DNA has been detected in neck lymph node (LN) metastases of HPV16-positive OPSCC, its significance remains controversial. Does this presence correlate to metastatic involvement or is it just the consequence of LN filter function?

OBJECTIVES

This study aims to analyse the relationship between HPV16 detection in neck LNs of HPV16-positive OPSCC and their pathological status.

STUDY DESIGN

HP16-viral load (VL) was quantified by real-time-polymerase-chain reaction in primary tumours and neck LNs, in 11 patients with HPV16-positive OPSCC and in three patients with HPV16-negative OPSCC. HPV16 in situ hybridisation and p16 immunohistochemistry were performed in all LNs.

RESULTS

A total of 45 LN levels were assessed. HPV16 DNA was not identified in HPV16-negative OPSCC LNs. All metastatic LNs from HPV16-positive OPSCC had a high VL and the viral DNA was located within tumoural cells. Among 27 pathologically tumour-free LN (PTFLN) levels 16/27 had no detectable VL, whereas the VL was low or medium (<10(5)copies/million cells) in 8/27 and high (>10(5)copies/million cells) in 3/27 PTFLN. In the latter group, no metastatic cell was identified and the viral DNA was located in immune cells.

CONCLUSION

HPV16 detection in LN is explained by its presence within either metastatic cells or immune cells. HPV16 detection in PTFLN is not necessarily correlated to occult LN metastases.

Validation of tumor markers in central nervous system germ cell tumors by real-time reverse transcriptase polymerase chain reaction using formalin-fixed paraffin-embedded tissues

The therapeutic protocols for treatment of germinomas and non-germinomatous germ cell tumors (NGGCTs) are completely different, so it is important to distinguish pure germinomas from NGGCTs. As it can be difficult to diagnose by morphology alone, immunohisto-chemistry (IHC) has been widely used as an ancillary test to improve diagnostic accuracy. However, IHC has limitations due to the misinterpretation of results or the aberrant loss of immunoreactivity. However, real-time RT-PCR has certain advantages over IHC, including its quantitative nature. The aim of our study was to evaluate the usefulness of real-time RT-PCR on formalin-fixed paraffin-embedded (FFPE) tissue blocks for the diagnosis of germ cell tumors of the central nervous system. We selected eight markers of germ cell tumors using a literature search, and validated them using real-time RT-PCR. Among them, POU5F1, NANOG and TGFB2 were statistically significant (P=0.05) in multiple comparisons (MANOVA) of three groups (pure germinomas, mature teratomas and malignant germ cell tumors). Two-group (pure germinomas and NGGCTs) discriminant analysis achieved a 70.0% success rate in cross-validation. We concluded that real-time RT-PCR using FFPE tissue has adequate validating power comparable to IHC in the diagnosis of central nervous system germ cell tumors; therefore, when IHC is not available, not conclusive or not informative, RT-PCR is a potential alternative to a repeat biopsy.

DSG3 as a biomarker for the ultrasensitive detection of occult lymph node metastasis in oral cancer using nanostructured immunoarrays

OBJECTIVES

The diagnosis of cervical lymph node metastasis in head and neck squamous cell carcinoma (HNSCC) patients constitutes an essential requirement for clinical staging and treatment selection. However, clinical assessment by physical examination and different imaging modalities, as well as by histological examination of routine lymph node cryosections can miss micrometastases, while false positives may lead to unnecessary elective lymph node neck resections. Here, we explored the feasibility of developing a sensitive assay system for desmoglein 3 (DSG3) as a predictive biomarker for lymph node metastasis in HNSCC.

MATERIALS AND METHODS

DSG3 expression was determined in multiple general cancer- and HNSCC-tissue microarrays (TMAs), in negative and positive HNSCC metastatic cervical lymph nodes, and in a variety of HNSCC and control cell lines. A nanostructured immunoarray system was developed for the ultrasensitive detection of DSG3 in lymph node tissue lysates.

RESULTS

We demonstrate that DSG3 is highly expressed in all HNSCC lesions and their metastatic cervical lymph nodes, but absent in non-invaded lymph nodes. We show that DSG3 can be rapidly detected with high sensitivity using a simple microfluidic immunoarray platform, even in human tissue sections including very few HNSCC invading cells, hence distinguishing between positive and negative lymph nodes.

CONCLUSION

We provide a proof of principle supporting that ultrasensitive nanostructured assay systems for DSG3 can be exploited to detect micrometastatic HNSCC lesions in lymph nodes, which can improve the diagnosis and guide in the selection of appropriate therapeutic intervention modalities for HNSCC patients.

Quantitative expression study of four cytokeratins and p63 in squamous cell carcinoma of the tongue: suitability for sentinel node navigation surgery using one-step nucleic acid amplification

Aims

Sentinel node navigation surgery (SNNS) is currently considered to provide better staging of regional metastasis. For rapid and accurate sentinel lymph node analysis, one-step nucleic acid amplification using cytokeratin 19 (CK19) has been applied, particularly in breast cancer. On the other hand, additional quantitative reverse transcription PCR targets containing cytokeratins have been reported recently in head and neck cancer. In this report, CK19 and p63 were immunohistochemically examined in primary tumours for use as molecular markers and were compared with cytokeratin 903 (CK903), cytokeratin 8/18 (CK8/18) and cytokeratin (AE1/AE3), which are used in diagnostic immunohistochemistry for head and neck squamous cell carcinoma.

Methods

The study reviewed 17 patients with T1/T2, N0 (UICC) oral squamous cell carcinoma of the tongue who were treated surgically at Kyorin University Hospital between 2002 and 2009. The intensity and proportion of tumour cells stained for CK19, CK903, p63, CK8/18 and AE1/AE3 were evaluated.

Results

CK19 and CK8/18 staining in cytoplasm was patchy among carcinoma cells, indicating weak expression. Staining proportion for p63, CK903 and AE1/AE3 was greater than for CK19 and CK8/18, although staining intensity for CK903 was weaker than for p63 and AE1/AE3. The difference in total score between CK19 and CK8/18 staining and p63, CK903 and AE1/AE3 staining was statistically significant (p<0.001). p63 and AE1/AE3 may be better markers than CK903, CK19 and CK8/18.

Conclusions

This suggests that p63 is of clinical utility in SNNS and that CK19 is unsuitable for early tongue carcinoma. Further studies are needed before clinical application of these markers.

Gene expression profiling in head and neck squamous cell carcinoma: Clinical perspectives

BACKGROUND

To date, more than 60 gene expression profiling (GEP) studies have been published in the field of head and neck squamous cell carcinoma (HNSCC) with variable objectives, methods, and results.

METHODS

The purpose of this study was to present a state-of-the-art review of GEP in HNSCC focusing on the current advances and perspectives for clinical applications.

RESULTS

Gene expression signatures have been developed to identify screening and diagnostic molecular markers, to improve tumor staging (cervical lymph node and distant metastasis prediction), to differentiate lung metastasis of HNSCC from primary lung squamous cell carcinoma, to predict tumor response to chemoradiotherapy, and to provide outcome predictors.

CONCLUSION

Some transcriptional signatures that could improve HNSCC management have been identified, but further analyses are required to properly validate and to precisely evaluate their clinical relevance. After an exploratory phase, the completion of large scale projects with stringent methodology is now necessary to transfer GEP from bench to bedside.

Joint practice guidelines for radionuclide lymphoscintigraphy for sentinel node localization in oral/oropharyngeal squamous cell carcinoma

Involvement of the cervical lymph nodes is the most important prognostic factor for patients with oral/oropharyngeal squamous cell carcinoma (OSCC), and the decision whether to electively treat patients with clinically negative necks remains a controversial topic. Sentinel node biopsy (SNB) provides a minimally invasive method of determining the disease status of the cervical node basin, without the need for a formal neck dissection. This technique potentially improves the accuracy of histological nodal staging and avoids over-treating three-quarters of this patient population, minimizing associated morbidity. The technique has been validated for patients with OSCC, and larger-scale studies are in progress to determine its exact role in the management of this patient population. This article was designed to outline the current best practice guidelines for the provision of SNB in patients with early-stage OSCC, and to provide a framework for the currently evolving recommendations for its use. These guidelines were prepared by a multidisciplinary surgical/nuclear medicine/pathology expert panel under the joint auspices of the European Association of Nuclear Medicine (EANM) Oncology Committee and the Sentinel European Node Trial Committee.

Neck restaging with sentinel node biopsy in T1-T2N0 oral and oropharyngeal cancer: Why and how?

Objective: To evaluate the lack of accuracy in neck staging with the classical technique (i.e., neck dissection and routine histopathology) with the sentinel node (SN) biopsy in oral and oropharyngeal T1-T2N0 cancer.

Study Design: Cross-sectional study with planned data collection.

Setting: Tertiary center care.

Subjects and Methods: In 50 consecutive patients, the pathological stage of sentinel node (pSN) was established after analyzing SN biopsies (n = 148) using serial sectioning and immunohistochemistry. Systematic selective neck dissection was performed. The pN stage was established with routine histopathologic analysis of both the non-SN (n = 1075) and the 148 SN biopsies.

Results: The sensitivity and negative predictive value of pSN staging were 100 percent. Conversely, if one considers pSN staging procedure as the reference test for micro- and macro-metastasis diagnosis, the sensitivity of the classical pN staging procedure was 50 percent (9/1; 95% CI 26.9-73.1) and its negative predictive value was 78 percent (95% CI 61.9-88.8). Fifteen patients (30%) were upstaged, including nine cases from pN0 to pSN ≥ 1 and six cases from pN1 to pSN2. Two of the pN0-pSN1 upstaged patients died with relapsed neck disease.

Conclusion: The SN biopsy technique appeared to be the best staging method in cN0 patients and provided evidence that routinely undiagnosed lymph node invasion may have clinical significance.

Pemphigus vulgaris antigen mRNA quantification for the staging of sentinel lymph nodes in head and neck cancer

Background:

Molecular diagnosis has been proposed to enhance the intra-operative diagnosis of sentinel lymph node (SLN) invasion in head and neck squamous cell carcinoma (HNSCC). Although cytokeratin (CK) mRNA quantification with real-time reverse transcriptase-PCR (QRT–PCR) has produced encouraging results, the more discriminating markers remain to be identified.

Methods:

Pemphigus vulgaris antigen (PVA), squamous cell carcinoma antigen (SCCA), and CK17 mRNA were quantified using QRT–PCR, and the results were compared with an extensive histopathological examination of the entire SLNs on 78 SLNs harvested from 22 patients with HNSCC.

Results:

SCCA and CK17 quantification showed significantly higher mRNA values for macrometastases (MAs) than for either negative or isolated tumour cell (ITC) SLNs (P<0.01). Pemphigus vulgaris antigen allowed the discrimination of all MAs and micrometastases from both negative and ITC SLNs (P<0.001). For the neck staging of patients, considering metastatic vs non-metastatic status, receiver-operating characteristic curve analysis found areas under the curve of 93.8, 97.9, and 100% for CK17, SCCA, and PVA, respectively. With PVA, a cutoff value of 562 copies per 100 ng of cDNA permitted the correct distinction between patients with positive as opposed to negative neck nodes in all cases.

Conclusion:

PVA seems to be a highly promising marker for accurate intra-operative SLN staging in HNSCC by QRT–PCR.

Joint Practice Guidelines for Radionuclide Lymphoscintigraphy for Sentinel Node Localization in Oral/Oropharyngeal Squamous Cell Carcinoma

Involvement of the cervical lymph nodes is the most important prognostic factor for patients with oral/oropharyngeal squamous cell carcinoma (OSCC), and the decision of whether to electively treat patients with clinically negative necks remains a controversial topic. Sentinel node biopsy (SNB) provides a minimally invasive method for determining the disease status of the cervical node basin, without the need for a formal neck dissection. This technique potentially improves the accuracy of histologic nodal staging and avoids overtreating three-quarters of this patient population, minimizing associated morbidity. The technique has been validated for patients with OSCC, and larger-scale studies are in progress to determine its exact role in the management of this patient population. This document is designed to outline the current best practice guidelines for the provision of SNB in patients with early-stage OSCC, and to provide a framework for the currently evolving recommendations for its use. Preparation of this guideline was carried out by a multidisciplinary surgical/nuclear medicine/pathology expert panel under the joint auspices of the European Association of Nuclear Medicine (EANM) Oncology Committee and the Sentinel European Node Trial (SENT) Committee.

Micrometastases and isolated tumour cells in sentinel lymph nodes in oral and oropharyngeal squamous cell carcinoma

BACKGROUND

The occurrence of micrometastases (MMs) and isolated tumour cells (ITCs) in oral sentinel lymph node (SLN) biopsy is poorly known, and the definitions and clinical significance of MMs and ITCs in SLN biopsy are controversial. We compared the UICC/TNM definitions of MMs and ITCs with our previously published sentinel node protocol to assess how the adoption of the UICC/TNM criteria would affect the staging of nodal micrometastatic disease.

METHODS

Of 107 patients who had a SLN biopsy and pathology at 150 microm intervals, 35 with metastatic tumour were included. Eighty-six SLNs were reassessed using the UICC/TNM definitions for MMs and ITCs. Findings were linked to the final pathology in the subsequent neck dissection.

RESULTS

Initial H&E sections showed metastases in 24 patients (in 34 out of 61 SLN), 8 of whom (9 SLNs) had MMs. Additional step serial sections revealed metastatic deposits in a further 11 patients (15 out of 25 SLNs were positive) which were reassessed as MMs (6 patients) or ITCs (5 patients). Subsequent neck dissection revealed additional metastases in 46% of patients with MM, whilst one of the ITC patients had subsequent neck metastases (20%).

CONCLUSION

Despite some limitations, the UICC/TNM classification provides an objective, uniform method of detecting MMs and ITC's. Unlike in cases with ITC, metastases in other non-SLNs were common when a micrometastasis was detected in a SLN, indicating need for further treatment of the neck.

Detection of lymph node micrometastases in patients with squamous carcinoma of the head and neck

While the significance of large cervical node metastases in patients with head and neck squamous carcinomas is well established, the import of a finding of regional nodal micrometastases (where a micrometastasis is defined as a metastatic deposit greater than 0.2 mm and not greater than 2.0 mm in greatest dimension) or isolated tumor cells in those patients is less clearly understood. Some earlier investigators have suggested that finding micrometastases does not have an impact on prognosis; some later investigators, however, have taken issue with this position, arguing that finding either micrometastases or isolated tumor cells might portend a poorer prognosis for head and neck cancer patients. At this juncture, it is difficult to advance a single recommendation for handling a finding of micrometastases or isolated tumor cells. It would be helpful if two courses of action were followed: first, while the detection of micrometastases and isolated tumor cells remains an investigatory practice, data should be collected and analyzed with an eye to discerning whether such findings are indeed of significance to the individual head and neck cancer patient. Second, rigorous definitions of micrometastases and isolated tumor cells (such as the definitions suggested here) should be developed and widely employed so as to permit ready comparison between the results as they are reported by different investigators.

Cytokeratin 17 mRNA expression has potential for diagnostic marker of oral squamous cell carcinoma

PURPOSE

Determination of marker for identification of oral squamous cell carcinoma (OSCC) is important for early diagnosis and individual therapy. Cytokeratins (CKs) like CK 19 and CK 20 are known to be useful diagnostic and prognostic markers for solid tumors. The aim of this study was to evaluate the relevance of further CKs for diagnosis of OSCC.

MATERIALS

In 10 OSCC and 5 normal mucosal samples, the expression patterns of 31 CK genes were examined by cDNA microarray in order to identify CKs with most pronounced over-expression. The results were verified for CK 17, CK 19, and CK 20 in addition to 46 OSCC samples by relative quantification (RQ) using SYBR green real-time reverse transcriptase polymerase chain reaction (RT qPCR). A correlation of the CK expressions with the tumor classification was carried out.

RESULTS

cDNA microarray analyses showed that out of all CKs, CK 17 was up-regulated strongest in OSCC compared to normal samples, and over-expression was most significantly associated with diagnosis (P = 0.002). Expression rates of CK 19 and CK 20 were not significantly different between OSCC samples and normal samples. In 56 samples analyzed by real-time RT qPCR, CK 17 was over-expressed in 53 (94.6%), CK 19 in 18 (32.1%), and CK 20 in 7 (12.5%). The over-expression of CK 17 was significantly associated with metastases of neck lymph nodes (P < 0.05). CK 19 was significantly over-expressed in T3 and T4 OSCC, in stage III and IV patients (P < 0.05), and in poorly differentiated OSCC (P < 0.03). The over-expression of CK 20 was significantly associated with metastases of neck lymph nodes (P < 0.03). Determined by RQ, the mean value of CK 17 over-expression was significantly higher than that of the other CKs (P < 0.01), and was significantly associated with T1 and T2 OSCC (P < 0.03) and with stage I and II patients (P < 0.01).

CONCLUSION

CK 19 might be linked to the clinical progression and differentiation of OSCC, and CK 20 could be associated with metastases of neck lymph nodes in OSCC. Due to the significant up-regulation and the strong over-expression, CK 17 might be the most suitable marker for diagnosis of OSCC out of the CK-family.

The clinical significance of disseminated tumor cells in breast cancer

The presence of tumor cells in the bone marrow of primary breast cancer patients at surgery has been shown to be an independent prognostic indicator of relapse. Tumor cells have been detected either directly, using immunocytochemical staining, or indirectly, using reverse transcription-polymerase chain reaction (RT-PCR). Studies have been initiated to determine whether the presence of disseminated cells can be monitored during the therapy of patients with primary breast cancer, and thus potentially be used to predict relapse before overt metastases are detectable. Studies are also ongoing to improve methods of detection, such as immunobead enrichment followed by staining and real-time RT-PCR, and to find alternative markers for the disseminated cells. Studies of patients with overt metastases have shown that there is a large tumor load in the peripheral blood and that this predicts overall survival. This article reviews the published literature on studies carried out in both primary and metastatic breast cancer patients, the methodologies and markers used, and improvements in detection methodologies that are being investigated including real-time RT-PCR, novel markers, enrichment and automated image analysis.