acp Best Practice No 169. Evidence based pathology: squamous carcinoma of the hypopharynx

Bone Marrow Mesenchymal Stem Cells Promote the Stemness of Hypopharyngeal Cancer Cells

A study was to investigate the regulation of bone marrow mesenchymal stem cells (BMSCs) on the stemness of hypopharyngeal cancer cells (FaDu cells). Green fluorescent protein-labeled FaDu cells were cocultured with BMSCs and then were isolated. In vitro experiments, including cell cycle and apoptosis analyses and clonogenic and sphere formation assays, were conducted using the cocultured FaDu cells to determine the stemness of FaDu cells. The tumor formation assay was performed through subcutaneous injection of FaDu cells into nude mice to determine the tumorigenic ability of FaDu cells after coculture. Immunohistochemical analysis of CD44 and ALDH1 was performed on the tumor tissue. After coculturing with human BMSCs, the ratio of FaDu cells at G2 phase was increased, while the ratios at S and G1 phases were decreased. In addition, coculture reduced apoptosis, but increased the clonogenic ability and sphere formation efficiency of FaDu cells. Finally, coculturing FaDu cells induced more robust and faster tumor formation as well as increased expression levels of CD44 and ALDH1 in tumor tissue. BMSCs promote the stemness of hypopharyngeal cancer cells.

PCDH20 acts as a tumour-suppressor gene through the Wnt/β-catenin signalling pathway in hypopharyngeal squamous cell carcinoma

BACKGROUND

Downregulation of PCDH20 is frequently involved in tumorigenesis of many cancers, but the role of PCDH20 protein in hypopharyngeal squamous cell carcinoma (HSCC) is still unknown.

OBJECTIVE

The aim of this study was to investigate the role of PCDH20 in hypopharyngeal squamous cell carcinoma (HSCC).

METHODS

Immunohistochemistry (IHC) and qRT-PCR was carried out to estimate the expressions of PCDH20 protein and mRNA in HSCC tissues and adjacent non-tumor tissues. Correlation between the PCDH20 expression and clinicopathological characteristics was evaluated using chi-square test. Meanwhile, Kaplan-Meier method and log-rank test were applied to analyze the overall survival. After transfection of PCDH20, the CCK8 assay, Cell migration assay and invasion assay were used to investigate the changes in the viability, migration and invasion of Fuda cells. The mechanisms by which reduced PCDH20 promote migration and invasion of Fuda cells were examined using western blotting.

RESULTS

PCDH20 protein showed in tumor tissue low expression rates of 67.5% (54/80). The mRNA of PCDH20 indicated the consistent trend (80%, 8/10). Reduced PCDH20 expression was positively related to T stage and lymph node metastasis (P< 0.05). Patients with low levels of PCDH20 had worse overall survival compared with those with high PCDH20 levels (P< 0.001). The univariate Cox regression analysis described that lymph node metastasis (P= 0.043) and down-regulated PCDH20 expression (P= 0.045) were significantly prognostic factors.Multivariate analysis suggested that low PCDH20 expression (P= 0.015) were significantly independent prognostic factors for overall survival. PCDH20 in Fadu cells significantly inhibited cell viability, migration and invasion. Meanwhile, PCDH20 was involved in the disruption of HSCC progression through antagonizing its downstream Wnt/β-catenin signalling pathway.

CONCLUSION

Our data highlight that the downregulated PCDH20 may serve as reliable diagnostic biomarker in HSCC.

Open-neck organ preservation surgery for hypopharyngeal cancer: indications, techniques, limits, and outcomes

PURPOSE OF REVIEW

To appraise the practice and role of open-neck organ preserving surgery for hypopharyngeal squamous cell carcinoma and to update the current indications, techniques, limits, and outcomes.

RECENT FINDINGS

The role of primary surgery for hypopharyngeal carcinoma has shifted over the past two decades to primary nonsurgical management with the use of induction or concurrent chemoradiotherapy. The preferred and most suitable tumours for open-neck surgery are the small-volume T stage diseases, with small to medium-volume neck metastases, however such patients are exceedingly rare. Nonetheless, more advanced tumours with cartilage invasion, vocal cord paralysis, or located at piriform apex and postcricoid area, previously unsuitable for open-neck organ preserving surgery, can now be excised and repaired, minimizing morbidity and improving quality of patients' life. Much of this surgical progress has been developed by innovative surgeons using free tissue transfer, accurate placement surgery, reconstruction of a neoglottis, and perfecting the pharyngoesophageal anastomosis. Current practice of open-neck organ preserving surgery for hypopharyngeal carcinoma has been mainly reported in Asia: Korea, Taiwan, Japan, and China.

SUMMARY

There are some patients who are deemed unsuitable and/or unwilling for current treatment by nonsurgical approaches, and open-neck organ preserving laryngopharyngeal surgery may be a more suitable alternative than selecting a 'lesser or modified' chemo or bioradiotherapy regimen, resulting in a prolonged quantity and quality of life.

How Histopathologic Tumor Extent and Patterns of Recurrence Data Inform the Development of Radiation Therapy Treatment Volumes in Solid Malignancies

The ability to deliver highly conformal radiation therapy using intensity-modulated radiation therapy and particle therapy provides for new opportunities to improve patient outcomes by reducing treatment-related morbidities following radiation therapy. By reducing the volume of normal tissue exposed to radiation therapy (RT), while also allowing for the opportunity to escalate the dose of RT delivered to the tumor, use of conformal RT delivery should also provide the possibility of expanding the therapeutic index of radiotherapy. However, the ability to safely and confidently deliver conformal RT is largely dependent on our ability to clearly define the clinical target volume for radiation therapy, which requires an in-depth knowledge of histopathologic extent of different tumor types, as well as patterns of recurrence data. In this article, we provide a comprehensive review of the histopathologic and radiographic data that provide the basis for evidence-based guidelines for clinical tumor volume delineation.

The central role of HOTAIR in the malignancy of CD44+ human hypopharyngeal carcinoma cells

Human hypopharyngeal carcinoma is one of the most common malignant tumors. CD44 could serve as a molecular marker to screen for cancer stem cells (CSCs) in hypopharyngeal cancer. The aim of this study was to identify the role of HOX transcript antisense RNA (HOTAIR) on cell proliferation and invasion in CD44+ FADU cells (human hypopharyngeal carcinoma cells). We also explored the underlying mechanism contributing to HOTAIR's observed effects. CD44+ FADU cells were sorted and purified by flow cytometry and infected with lentivirus stably expressing HOTAIR shRNA. Cell proliferation and invasion analyses were carried out with cell counting kit-8 (CCK-8) and Transwell assays. The expressions of downstream effectors of HOTAIR, including E-cadherin, β-catenin, and vimentin were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. Knockdown of HOTAIR markedly inhibited the proliferation and invasion of CD44+ FADU cells in vitro. HOTAIR depletion also increased the expressions of tumor suppressors E-cadherin and β-catenin and decreased the expression of oncogenic vimentin at both mRNA and protein levels. Collectively, our results show that HOTAIR can suppress CD44+ FADU cells proliferation and invasion by regulating the expressions of E-cadherin, β-catenin, and vimentin.

Evidence-based pathology: systematic literature reviews as the basis for guidelines and best practices

CONTEXT

Evidence-based medicine has been proposed as a new paradigm for the identification and evaluation of medical information. Best available evidence or data are identified and used as the basis for the diagnosis and treatment of individual patients. Evidence-based pathology has adapted basic evidence-based medicine concepts to the specific needs of pathology and laboratory medicine.

OBJECTIVES

To briefly review the history and basic concepts of evidence-based medicine and evidence-based pathology, describe how to perform and interpret systematic reviews, and discuss how to integrate best evidence into guidelines.

DATA SOURCES

PubMed (National Library of Medicine, Washington, DC) and Web of Science (Thompson Reuters, New York, New York) were used.

CONCLUSIONS

Evidence-based pathology provides methodology to evaluate the quality of information published in pathology journals and apply it to the diagnosis of tissue samples and other tests from individual patients. Information is gathered through the use of systematic reviews, using a method that is less biased and more comprehensive than ad hoc literature searches. Published data are classified into evidence levels to provide readers with a quick impression about the quality and probable clinical validity of available information. Best available evidence is combined with personal experience for the formulation of evidence-based, rather than opinion-based, guidelines that address specific practice needs.

Esophagus and hypopharyngeal reconstruction

This article reviews the literature on esophageal reconstruction. The most common methods used are gastric pull-up, pectoralis major flap, colon interposition, fasciocutaneous flaps (radial forearm free flap or anterolateral thigh flap), and free jejunum and colon flaps. The stricture rates, fistula rates, morbidity, and mortality of each flap are reviewed.

Sonographic assessment of hypopharyngeal carcinoma: preliminary study

OBJECTIVES

This study investigated the ability of sonography for diagnosis of hypopharyngeal carcinoma.

METHODS

Between November 2008 and January 2010, 34 consecutive patients with hypopharyngeal carcinoma (34 tumors) were examined by sonography. The visualization capability of sonography was evaluated by grading criteria of "excellent," "good," "moderate," and "poor" in comparison with computed tomography (CT). Localization of the primary tumor foci and intrahypopharyngeal and extrahypopharyngeal invasion were initially assessed by sonography and confirmed with surgical and pathologic findings. Laryngeal movement was observed on real-time sonography and compared with endoscopic findings.

RESULTS

On sonography, 29 of the 34 lesions (85.3%) were graded excellent, similar to the shapes and dimensions of the tumors on CT. Localization was correctly undertaken in 26 of the 28 foci resected (92.9%), with excellent agreement between sonography and surgical and pathologic findings (κ = 0.823; P < .001). In evaluating intrahypopharyngeal and extrahypopharyngeal invasion with sonography, the sensitivity and specificity were 90.9% and 82.4%, respectively, for intrahypopharyngeal intersubsite spreading, 50.0% and 96.2% for diagnosis of thyroid cartilage destruction, both 100% for evaluation of cervical esophagus, neck soft tissue, and thyroid gland involvement, and 76.9% and 100% for assessment of hemilarynx fixation.

CONCLUSIONS

Sonography has a similar role in visualization of hypopharyngeal carcinoma as CT and is satisfactory in localization of the primary focus and assessment of tumor extension inside and outside the hypopharynx.

miR-489 is a tumour-suppressive miRNA target PTPN11 in hypopharyngeal squamous cell carcinoma (HSCC)

Background:

Hypopharyngeal squamous cell carcinoma (HSCC) is an aggressive malignancy with one of the worst prognoses among all head and neck cancers. Greater understanding of the pertinent molecular oncogenic pathways could help improve diagnosis, therapy, and prevention of this disease. The aim of this study was to identify tumour-suppressive microRNAs (miRNAs), based on miRNA expression signatures from clinical HSCC specimens, and to predict their biological target genes.

Methods:

Expression levels of 365 human mature miRNAs from 10 HSCC clinical samples were screened using stem-loop real-time quantitative PCR. Downregulated miRNAs were used in cell proliferation assays to identify a tumour-suppressive miRNA. Genome-wide gene expression analyses were then performed to identify the target genes of the tumour-suppressive miRNA.

Results:

Expression analysis identified 11 upregulated and 31 downregulated miRNAs. Gain-of-function analysis of the downregulated miRNAs revealed that miR-489 inhibited cell growth in all head and neck cancer cell lines examined. The gene PTPN11 coding for a cytoplasmic protein tyrosine phosphatase containing two Src Homology 2 domains was identified as a miR-489-targeted gene. Knockdown of PTPN11 resulted in the inhibition of cell proliferation in head and neck SCC cells.

Conclusion:

Identification of the tumour-suppressive miRNA miR-489 and its target, PTPN11, might provide new insights into the underlying molecular mechanisms of HSCC.

[Pathological changes of the hypopharynx in the focus of imaging]

The spectrum of pathological changes in anatomical sections of the hypopharynx ranges from benign pathologies to hypopharyngeal carcinoma. Beside the clinical status and the endoscopic evaluation performed by ear, nose and throat specialists, imaging techniques play an important role in pre-therapeutic and post-therapeutic diagnostics and in the follow-up of pharyngeal disease patterns, especially for malignant lesions. A conventional x-ray swallow examination, contrast-enhanced multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI), as well as positron emission tomography (PET) and positron emission tomography computed tomography (PET-CT) are applied depending on the medical question and disease. Especially in radiological oncology, it is extremely important in regions which are clinically difficult to assess to determine the exact localization and extent of hypopharyngeal pathologies to plan the optimal therapy for the patient. This article demonstrates the radiological appearance of pathological changes of the hypopharynx and discusses in particular the hypopharynx carcinoma in the focus of pre-therapeutic and post-therapeutic imaging.

Hypopharyngeal cancer

Hypopharyngeal cancers are usually squamous cell carcinomas (SCCs) that has the worst prognosis among the head and neck cancers. Overall, 5-year survival rate remains poor despite recent improvements in diagnostic imaging, radiation and chemotherapy, and improved surgical techniques. Hypopharyngeal cancers tend to present with advanced primary disease, and nodal metastasis is highly likely. The most important features determining prognosis are the size and extent of local spread of the primary carcinoma and the extent of involvement of regional lymph nodes. Distant metastasis at presentation is more common in hypopharyngeal cancers than in other head and neck cancers. Poor survival rate is partly due to emergence of second primary cancers but also to development of distant metastasis. Contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) remain the mainstay of initial radiological evaluation of hypopharyngeal cancer. Imaging usually results in upstaging of the tumor at presentation. Meticulous evaluation of the extent of the primary tumor with attention to spread to the subsites of the hypopharynx, larynx, and cartilage invasion are necessary for accurate staging. After surgery and radiation therapy, it is difficult with CT and MR to differentiate residual and recurrent tumor from edema and scarring. Fluorine 18-fluoro-deoxy-glucose -positron emission tomography (FDG-PET) has high sensitivity in detection of occult, residual, and recurrent tumors but has low specificity. Combined PET and CT increase specificity and are increasingly being used to image posttreatment cases. Other newer imaging modalities such as diffusion-weighted imaging (DWI), MR spectroscopy, and MRI with superparamagnetic iron oxide (SPIO) contrast agent are reported to be useful and should be used more widely in difficult cases.

[Regional failure of hypopharyngeal squamous cell carcinoma]

PURPOSE

Lymph nodes and distant metastases contribute to the poor prognosis of hypopharyngeal squamous cell carcinoma. The purpose of this study is to estimate the frequency, mode and prognosis factors related to regional and distant metastasis.

PATIENTS AND METHOD

The authors' report is based on a retrospective study concerning 271 hypopharyngeal squamous cell carcinoma, compiled in the service of Surgery of Head and Neck Cancers of the Salah-Azaïz Institute (1977-2002). Frequency and histoclinical characters of cervical and distant metastases have been assessed, as well as their prognosis factors among 155 patients treated in a curative purpose.

RESULTS

39.1% of the tumours were classified N0, 24.4% N1, 10.7% N2 and 25.8% N3 (UICC 2002). The cervical nodal invasion was significantly more frequent for the classified tumors T3T4 than for the T1T2 (for pyriform sinus, postcricoid esophagus, posterior wall, and total hypopharynx, respectively : P =0.001, P =0.007, P =0.047 and P =0.0005). A cervical lymphatic evidement was preferred in thirty two patients. Among N0, 46.9% were N+; The frequencies of the capsular effraction were not significantly different for the N0N1 from for the N2N3 (P =0.11). The two and five years survival rates were respectively 32.5 and 20.5% for N0, and 10.9% and zero for N3. The survival differences after two and five years between the N0N1 and the N2N3 were significant (P =0.04). A regional failure was noticed for 18.5% of the patients. The tumoral site did not influence significantly the rate of nodal failure (P =0.98), neither the clinical status N (P =0.34). Capsular effraction was a significant factor for the regional failure (P =0.007). Distant metastasis significantly occurred more frequently among the patients initially classified N2N3 than those classified N0N1 (P =0.03), and in case of capsular effraction (P =0.0009).

CONCLUSION

Hypopharyngeal squamous cell carcinoma has a high rate of lymph nodes metastasis, correlated to the local extension, and a high rate of occult nodal metastasis. Lymph node clinical status does not seem to have influenced the patients survival; however, capsular effraction constitutes a major prognosis factor of regional failure and distant metastasis. Distant metastases are frequent, particularly in case of wide local and regional tumoral extension.