Importance of molecular analysis in detecting cervical lymph node metastasis in head and neck squamous cell carcinoma

Stathmin1 promotes lymph node metastasis in hypopharyngeal squamous cell carcinoma via regulation of HIF‑1α/VEGF‑A axis and MTA1 expression

Extensive neck lymph node metastasis (LNM) is an important clinical feature of hypopharyngeal squamous cell carcinoma (HSCC). Stathmin1 (STMN1) is closely associated with LNM in numerous human cancers. In the present study, the association between STMN1 and neck LNM in HSCC and the underlying molecular mechanisms were explored. First, postoperative samples of HSCC were screened and the association between STMN1 and neck LNM in HSCC was analyzed. Then, cell functional experiments were performed to assess the potential of STMN1 to promote invasion and migration. Subsequently, the potential target genes and pathways of STMN1 were predicted using bioinformatics analysis. Finally, the obtained target genes and pathways of STMN1 were validated by reverse transcription-quantitative PCR (RT-qPCR) and western blot analyses to confirm the potential mechanisms by which STMN1 promotes LNM in HSCC. As a result, a total of 117 postoperative samples of HSCC were screened, and STMN1 was proven to be associated with neck LNM in HSCC. Further, cell functional experiments established that high expression of STMN1 could actually promote FaDu cell invasion and metastasis. Bioinformatics analysis revealed that high expression of STMN1 was associated with the activation of hypoxia inducible factor-1alpha (HIF-1α) pathway and increased expression of metastasis-associated protein 1 (MTA1). Finally, RT-qPCR and western blot analyses confirmed that STMN1 promotes the expression levels of HIF-1α/vascular endothelial growth factor (VEGF)-A and MTA1 in FaDu cell lines. In conclusion, it was found that high expression of STMN1 promoted neck LNM in HSCC and the potential mechanisms may be via regulation of the HIF-1α/VEGF-A axis and MTA1 expression.

miR-30e-5p represses angiogenesis and metastasis by directly targeting AEG-1 in squamous cell carcinoma of the head and neck

Metastasis is a critical determinant for the treatment strategy and prognosis in patients with squamous cell carcinoma of the head and neck (SCCHN). However, the mechanisms underlying SCCHN metastasis are poorly understood. Our study sought to determine the key microRNA and their functional mechanisms involved in SCCHN metastasis. For The Cancer Genome Atlas (TCGA) data analysis, quantitative PCR was used to quantify the level of miR-30e-5p in SCCHN and its clinical significance was further analyzed. A series of in vitro and in vivo experiments were applied to determine the effects of miR-30e-5p and its target AEG-1 on SCCHN metastasis. A mechanism investigation further revealed that AEG-1 was implicated in the angiogenesis and metastasis mediated by miR-30e-5p. Overall, our study confirms that miR-30e-5p is a valuable predictive biomarker and potential therapeutic target in SCCHN metastasis.

One-step nucleic acid amplification for detecting lymph node metastasis of head and neck squamous cell carcinoma

BACKGROUND

In head and neck squamous cell carcinoma (HNSCC) 30% of cN0 patients have occult metastasis. LN invasion is a major prognostic factor. Sentinel lymph node (SLN) is an option for cN0 neck management. One-step nucleic acid amplification (OSNA) used to analyze SLN in breast cancer is also a candidate to get more reliable intraoperative HNSCC lymph node (LN) staging.

OBJECTIVE

To compare OSNA analysis to pathological analysis in cN0 HNSCC.

MATERIALS AND METHODS

157 LN from 26 cN0 HNSCC patients were prospectively analyzed (6.3LN/patient). Exclusion criteria were previous surgery or radiotherapy. Each node was cut into 4 equal pieces alternatively sent to pathological analysis and OSNA technique. IHC CK19 was performed on the primary tumor biopsy and RT-qPCR of CK19, PVA and EPCAM on the LN lysate of discordant cases.

RESULTS

OSNA was able to provide intraoperative result in all patients. OSNA detected 21 metastases. There were 139 concordant LN (88.5%). There were 18 initial discordant LN (11.5%), 13 (8.3%) were OSNA positive/pathological analysis negative, 5 (3.2%) were OSNA negative/pathological analysis positive. After elimination of allocation bias, false negative rate was 1.3%, sensitivity and specificity were 90% and 95.6%, PPV and NPV were 75% and 98.5%.

CONCLUSION

Our results suggest that OSNA should be considered to improve SNB analysis both for increasing micro metastasis diagnosis and offer extemporaneous results. Study registered under clinicaltrials.gov database number NCT02852343.

Wnt3a protein overexpression predicts worse overall survival in laryngeal squamous cell carcinoma

As a classical ligand in the canonical Wnt/β-catenin signaling pathway, the role of Wnt3a in laryngeal squamous cell carcinoma (LSCC) remains unclear. Therefore, the expression pattern of the Wnt3a protein in 222 primary LSCC, and 19 corresponding adjacent non-carcinoma specimens, was detected by immunohistochemistry and further correlated with clinicopathological parameters. The results showed that LSCC tissue expressed higher levels of the Wnt3a protein when compared to the corresponding adjacent non-cancerous tissues. High expression of Wnt3a was closely related to histological grade (P = 0.031), clinical stage (I+II / III+IV; P = 0.004), and lymph node metastasis (P = 0.03). Kaplan-Meier analysis evidenced that a worse overall survival (OS) was correlated to the group with high Wnt3a expression (P = 0.003). When stratified survival analyses were performed, patients with lymph node metastasis/advanced clinical stages and high Wnt3a expression had worse OS rates than patients with other features (P < 0.001). Finally, multivariate analysis showed that Wnt3a expression was an independent prognosis factor for LSCC patients. The current findings suggest that Wnt3a is tightly related to the LSCC progression and could serve as a valuable clinic biomarker for LSCC patients.

Tumor-associated macrophages derived CCL18 promotes metastasis in squamous cell carcinoma of the head and neck

Background

Alternatively activated macrophages in tumor microenvironment is defined as M2 tumor-associated macrophages (M2 TAMs) that promote cancer progression. However, communicative mechanisms between M2 TAMs and cancer cells in squamous cell carcinoma of head and neck (SCCHN) remain largely unknown.

Methods

Quantitative real-time PCR, western blotting, enzyme-linked immunosorbent assay and flow cytometry were applied to quantify mRNA and protein expression of genes related to M2 TAMs, epithelial–mesenchymal transition (EMT) and stemness. Wounding-healing and Transwell invasion assays were performed to detect the invasion and migration. Sphere formation assay was used to detect the stemness of SCCHN cells. RNA-sequencing and following bioinformatics analysis were used to determine the alterations of transcriptome.

Results

THP-1 monocytes were successfully polarized into M2-like TAMs, which was manifested by increased mRNA and protein expression of CCL18, IL-10 and CD206. Conditioned medium from M2-like TAMs promoted the migration and invasion of SCCHN cells, which was accompanied by the occurrence of EMT and enhanced stemness. Importantly, CCL18 neutralizing antibody partially abrogated these effects that caused by conditional medium from M2-like TAMs. In addition, recombinant human CCL18 (rhCCL18) correspondingly promoted the malignant biological behaviors of SCCHN in vitro. Finally, RNA-sequencing analysis identified 331 up-regulated and 363 down-regulated genes stimulated by rhCCL18, which were statistically enriched in 10 cancer associated signaling pathways.

Conclusion

These findings indicate that CCL18 derived from M2-like TAMs promotes metastasis via inducing EMT and cancer stemness in SCCHN in vitro.

Electronic supplementary material

The online version of this article (10.1186/s12935-018-0620-1) contains supplementary material, which is available to authorized users.

Accuracy of microRNAs as markers for the detection of neck lymph node metastases in patients with head and neck squamous cell carcinoma

BACKGROUND

The presence of metastatic disease in cervical lymph nodes of head and neck squamous cell carcinoma (HNSCC) patients is a very important determinant in therapy choice and prognosis, with great impact in overall survival. Frequently, routine lymph node staging cannot detect occult metastases and the post-surgical histologic evaluation of resected lymph nodes is not sensitive in detecting small metastatic deposits. Molecular markers based on tissue-specific microRNA expression are alternative accurate diagnostic markers. Herein, we evaluated the feasibility of using the expression of microRNAs to detect metastatic cells in formalin-fixed paraffin-embedded (FFPE) lymph nodes and in fine-needle aspiration (FNA) biopsies of HNSCC patients.

METHODS

An initial screening compared the expression of 667 microRNAs in a discovery set comprised by metastatic and non-metastatic lymph nodes from HNSCC patients. The most differentially expressed microRNAs were validated by qRT-PCR in two independent cohorts: i) 48 FFPE lymph node samples, and ii) 113 FNA lymph node biopsies. The accuracy of the markers in identifying metastatic samples was assessed through the analysis of sensitivity, specificity, accuracy, negative predictive value, positive predictive value, and area under the curve values.

RESULTS

Seven microRNAs highly expressed in metastatic lymph nodes from the discovery set were validated in FFPE lymph node samples. MiR-203 and miR-205 identified all metastatic samples, regardless of the size of the metastatic deposit. Additionally, these markers also showed high accuracy when FNA samples were examined.

CONCLUSIONS

The high accuracy of miR-203 and miR-205 warrant these microRNAs as diagnostic markers of neck metastases in HNSCC. These can be evaluated in entire lymph nodes and in FNA biopsies collected at different time-points such as pre-treatment samples, intraoperative sentinel node biopsy, and during patient follow-up. These markers can be useful in a clinical setting in the management of HNSCC patients from initial disease staging and therapy planning to patient surveillance.

Factors contributing to lymph node occult metastasis in supraglottic laryngeal carcinoma cT2-T4 N0M0 and metastasis predictive equation

OBJECTIVE

To investigate factors that contribute to lymph node metastasis (LNM) from clinical cT2-T4 N0M0 (cN0) supraglottic laryngeal carcinoma (SLC), and to predict the risk of occult metastasis before surgery.

METHODS

A total of 121 patients who received surgery were retrospectively analyzed. Relevant factors regarding cervical LNM were analyzed. Multivariate analyses were conducted to predict the region where the metastasis occurred and prognosis.

RESULTS

The overall metastatic rate of cN0 SLC was 28.1%. Metastatic rates were 15.4%, 32.5% and 35.7% for T2, T3 and T4, respectively. Metastatic rates for SLC levels II, III and IV were 19.6%, 17.2% and 3.6%, respectively. A regression equation was formulated to predict the probability of metastasis in cN0 SLC as follows: Pn=e((-3.874+0.749T3+1.154T4+1.935P1+1.750P2))/[1+e((-3.874+0.749T3+1.154T4+1.935P1+1.750P2))]. Approximately 0.2% of patients experienced LNM with no recurrence of laryngeal cancer. Comparison of the intergroup survival curves between patients with and without LNM indicated a statistically significant difference (P=0.029).

CONCLUSIONS

Cervical lymph node metastatic rates tended to increase in tandem with T stage in patients with LNM in cN0 SLC, and neck dissection is advised for these patients. Moreover, cervical LNM in cN0 SLC showed a sequential pattern and may be predicted.

Elevated expression of histone demethylase PHF8 associates with adverse prognosis in patients of laryngeal and hypopharyngeal squamous cell carcinoma

AIM

Overexpression of histone demethylase PHF8 has been reported to function as an oncoprotein in many cancers; however, the implications of PHF8 involvement in laryngeal and hypopharyngeal squamous cell carcinoma (LHSCC) remain unclear. This study aims to explore the expression of PHF8 and its clinical significance in LHSCC.

MATERIALS & METHODS

Western blotting and immunohistochemistry were performed to evaluate PHF8 protein expression in fresh and archived LHSCC samples. Global expressions of H3K27 and H3K9 methylation were analyzed in a cell line with PHF8 siRNA treatment.

RESULTS & CONCLUSION

In our study, PHF8 was upregulated in fresh LHSCC tissues. Immunohistochemical staining revealed that the expression of PHF8 was positively associated with T classification, clinical stage, primary tumor position and tumor relapse. Survival analysis demonstrated that high PHF8 expression was significantly associated with shorter overall survival and disease-free survival. Moreover, PHF8 regulates the levels of H3K9me2 and H3K27me2 in LHSCC. Taken together, PHF8 might be a novel prognostic marker for this disease.

Aberrant Myosin 1b Expression Promotes Cell Migration and Lymph Node Metastasis of HNSCC

Lymph node metastasis is the major clinicopathologic feature associated with poor prognosis in patients with head and neck squamous cell carcinoma (HNSCC). Here, web-based bioinformatics meta-analysis was performed to elucidate the molecular mechanism of lymph node metastasis of human HNSCC. Preferential upregulation of Myosin 1b (MYO1B) transcript in HNSCC datasets was identified. Myo1b mRNA was highly expressed in human HNSCC cells and patient tissue specimens compared with their normal counterparts as shown by quantitative PCR (qPCR) analyses. Immunohistochemistry (IHC)-detected Myo1b expression was significantly correlated with lymph node metastases in patients with oral cancer of the tongue. HNSCC with high expression of Myo1b and chemokine receptor 4 (CCR4), another metastasis-associated molecule, was strongly associated with lymph node metastasis. RNA interference (RNAi) of Myo1b in HNSCC cells, SAS and HSC4, significantly inhibited migratory and invasive abilities through decreased large protrusion formation of cell membranes. Finally, Myo1b knockdown in SAS cells significantly inhibited in vivo cervical lymph node metastases in a cervical lymph node metastatic mouse model system.

IMPLICATIONS

Myo1b is functionally involved in lymph node metastasis of human HNSCC through enhanced cancer cell motility and is an attractive target for new diagnostic and therapeutic strategies for patients with HNSCC.

Prognostic value of level IV metastases from head and neck squamous cell carcinoma

BACKGROUND

The purpose of this study was to evaluate the prognostic value of level IV metastases in head and neck squamous cell carcinoma (HNSCC).

METHODS

The clinical and histopathological data of 111 patients with HNSCC with pN+ neck who underwent a primary tumor resection with unilateral or bilateral neck dissection were analyzed.

RESULTS

Level IV metastases were histopathologically proven in 33 patients (29.7%). Pulmonary metastases were observed in 12 of 33 patients (36.4%) with level IV metastases, and in 13 of 78 patients (16.7%) without level IV metastases (p = .04). Multivariate analyzes revealed a significant association between level IV metastases and pulmonary metastases (p = .038). However, an influence on overall (p = .65) or disease-free survival (p = .66) was not observed.

CONCLUSION

Level IV metastases seem to be a predictive factor for pulmonary metastases but not for overall and disease-free survival in patients with HNSCC.

Silibinin induced the apoptosis of Hep-2 cells via oxidative stress and down-regulating survivin expression

Silibinin is an anticancer and chemopreventive natural compound, which is extracted from milk thistle (Silybum marianum). It is reported that silibinin has anticancer efficacy in many malignant tumors. Laryngeal carcinoma is the second most common head and neck squamous carcinoma. In the present work, we investigated the effects of silibinin on laryngeal squamous cell carcinoma (LSCC) cell line Hep-2 cells. We found that silibinin induced the decrease of cell viability in Hep-2 cells with a concentration- and time-dependent manner. Moreover, silibinin resulted in the apoptosis of Hep-2 cells and had synergy effects with arsenic trioxide. Intracellular reactive oxygen species (ROS) accumulation increased because of silibinin exposure. ROS scavenger NAC alleviated the cytotoxicity of silibinin to Hep-2 cells. The mitochondrial membrane potential (MMP) was lost in Hep-2 cells treated with silibinin. Subsequently, silibinin induced the activation of caspase-3 in Hep-2 cells and caspase inhibitor Z-VAD-FMK inhibited the cytotoxicity of silibinin in Hep-2 cells. The survivin expression decreased after Hep-2 cells were treated with silibinin. In conclusion, silibinin induced the apoptosis of Hep-2 cells via oxidative stress and down-regulating survivin expression. Therefore, silibinin is a potential therapeutical agent against LSCC in future.

Increased expression of metadherin protein predicts worse disease-free and overall survival in laryngeal squamous cell carcinoma

Metadherin (MTDH) is involved in tumourigenesis and cancer progression in multiple human malignancies. However, the MTDH protein has rarely been reported in laryngeal squamous cell carcinoma (LSCC). The expression pattern of the MTDH protein in 176 primary archival LSCC and 27 corresponding adjacent noncarcinoma specimens was detected by immunohistochemistry and further correlated with clinicopathological parameters. The results demonstrated that 161 (91.48%) primary LSCC samples stained positive for MTDH; however, staining was barely detectable in all adjacent noncarcinoma samples. Moreover, the expression of the MTDH protein was significantly associated with the primary tumour site (p = 0.021), T classification (p = 0.002), clinical stage (I + II/III + IV; p < 0.001), lymph node metastasis (p < 0.001) and postoperational recurrence (p < 0.001). Kaplan-Meier analysis revealed that MTDH expression was significantly associated with worse disease-free survival (DFS) and overall survival (OS) rates in patients with LSCC (both p < 0.001). When lymph node metastasis and MTDH expression were considered together, patients with lymph node metastasis and high MTDH expression had both poorer DFS and OS rates than others (both p < 0.001). Finally, multivariate analysis demonstrated that MTDH expression was an independent prognostic factor for both DFS and OS rates in patients with LSCC. Strong MTDH expression was negatively correlated with a canonical epithelial-mesenchymal transition molecule E-cadherin (p < 0.001) and positively associated with proangiogenic protein vascular endothelial growth factor (p < 0.001). MTDH overexpression was tightly associated with more aggressive tumour behaviour and a poor prognosis, indicating that MTDH is a valuable molecular biomarker for LSCC progression.

Autocrine and paracrine loops between cancer cells and macrophages promote lymph node metastasis via CCR4/CCL22 in head and neck squamous cell carcinoma

Lymph node metastasis is a poor prognostic factor for patients with head and neck squamous cell carcinoma (HNSCC). However, its molecular mechanism has not yet been fully understood. In our study, we investigated the expression of CCR4 and its ligand CCL22 in the HNSCC tumor microenvironment and found that the CCR4/CCL22 axis was involved in lymph node metastasis of HNSCC. CCR4 was expressed in 20 of 31 (64.5%) human tongue cancer tissues, and its expression was significantly correlated with lymph node metastasis (p < 0.01) and lymphatic invasion (p < 0.05). CCR4 was expressed in three of five human HNSCC cell lines tested. CCR4(+) HNSCC cells, but not CCR4(-) cells, showed enhanced migration toward CCL22, indicating that functional CCR4 was expressed in HNSCC cell lines. CCL22 was also expressed in cancer cells (48.4% of tongue cancer tissues) or CD206(+) M2-like macrophages infiltrated in tumors and draining lymph nodes. CCL22 produced by cancer cells or CD206(high) M2-like macrophages increased the cell motility of CCR4(+) HNSCC cells in vitro in an autocrine or paracrine manner. In the mouse SCCVII in vivo model, CCR4(+) cancer cells, but not CCR4(-) cells, metastasized to lymph nodes which contained CCL22 producing M2-like macrophages. These results demonstrate that lymph node metastasis of CCR4(+) HNSCC is promoted by CCL22 in an autocrine or M2-like macrophage-dependent paracrine manner. Therefore, the CCR4/CCL22 axis may be an attractive target for the development of diagnostic and therapeutic strategies for patients with HNSCC.

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.

Future of the TNM classification and staging system in head and neck cancer

Staging systems for cancer, including the most universally used TNM classification system, have been based almost exclusively on anatomic information. However, the question arises whether staging systems should be based on this information alone. Other parameters have been identified that should be considered for inclusion in classification systems like the TNM. This is all the more important, as a shift toward nonsurgical treatments for head and neck cancer has been made over the years. For these treatment modalities tumor/biologic characteristics next to anatomic information may be particularly important for treatment choice and outcome. The shortcomings of the current TNM classification system will be discussed, along with suggestions for improvement and expansion of the TNM system based on tumor, patient, and environment-related factors. Further improvement of the TNM classification is expected to result in better treatment choices, outcome and prognostication of patients with head and neck cancer.

Intraoperative qRT-PCR for detection of lymph node metastasis in head and neck cancer

PURPOSE

Sentinel node biopsy (SNB) has been shown to accurately stage the regional lymphatics in oral carcinoma. However, intraoperative pathology is only moderately sensitive and final pathology takes several days to complete. The purpose of this study was to develop a rapid, automated, and quantitative real-time PCR (qRT-PCR) assay that can match final pathology in an intraoperative time frame.

EXPERIMENTAL DESIGN

Four hundred forty-eight grossly tumor-negative lymph nodes were evaluated for expression of 3 markers [PVA (pemphigus vulgaris antigen), PTHrP (parathyroid hormone-related protein), and TACSTD1 (tumor-associated calcium signal transducer 1)]. Conformity of metastasis detection by qRT-PCR was determined using hematoxylin and eosin and immunohistochemistry staining as the gold standard. PVA and TACSTD1 were then multiplexed with β-glucuronidase to develop a rapid, automated single-tube qRT-PCR assay using the Cepheid GeneXpert system. This assay was used to analyze 103 lymph nodes in an intraoperative time frame.

RESULTS

Four hundred forty-two nodes produced an informative result for both qRT-PCR and pathologic examination. Concordance of qRT-PCR for individual markers with final pathology ranged from 93% to 98%. The best marker combination was TACSTD1 and PVA. A rapid, multiplex assay for TACSTD1 and PVA was developed on the Cepheid GeneXpert and demonstrated an excellent reproducibility and linearity. Analysis of 103 lymph nodes demonstrated 94.2% accuracy of this assay for identifying positive and negative nodes. The average time for each assay to yield results was 35 minutes.

CONCLUSIONS

A rapid, automated qRT-PCR assay can detect lymph node metastasis in head and neck cancer with high accuracy compared to pathologic analysis and may be more accurate than intraoperative pathology. Combined, SNB and rapid qRT-PCR could more appropriately guide surgical treatment of patients with head and neck cancer.

Cervical metastases of squamous cell carcinoma of the maxilla: a retrospective study of 9 years

PURPOSE

Metastases of squamous cell carcinoma of the tongue and the mouth floor have been well studied. Concerning maxilla squamous cell carcinomas, however, only a few studies have been performed. The question is whether a prophylactic neck dissection should be performed in these tumors.

PATIENTS AND MATERIAL

In the Department of Craniomaxillofacial Surgery at the University Hospital of Zurich, 30 patients who had been treated for squamous cell carcinoma of the maxilla were examined retrospectively. Special attention was paid to direct and late metastasis, survival rate, and treatment.

RESULTS

Of the 59 patients with upper jaw carcinomas over a 9-year period, only about half (30 patients) had a squamous cell carcinoma of the upper jaw. Of those patients, 27% had an upper lesion on the right side, 33% on the left. Of the 11 patients (36.7%) presenting positive lymph nodes, 4 patients had direct positive lymph nodes while 7 patients had later positive lymph nodes; and 71.4% of the late metastasis appeared during the first year.

CONCLUSION

Because of the 36.7% of patients presenting metastases in the cervical lymph nodes, elective neck treatment should be considered in cases even with a negative clinical examination.

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.

Management of the clinically negative neck (N0) of supraglottic laryngeal carcinoma: a systematic review

AIM

The most effective therapeutic approach for patients with supraglottic laryngeal carcinoma (SGLC) and clinically negative neck (cN0) remains a subject of much debate. The purpose of this systematic review was to answer the following question: among patients with SGLC and cN0 neck, are the survival and occurrence of neck metastases significantly different between patients that received neck dissection and those that had another therapeutic treatment (radiotherapy, combined therapy, 'wait and see' policy)?

MATERIALS AND METHODS

An electronic literature search was performed in MEDLINE, EMBASE, Cochrane Library and CENTRAL databases, followed by extensive hand-searching for the identification of relevant studies. The following inclusion criteria were established: the study should (a) include a comparison of neck dissection with one of the other therapeutic procedures for cN0 of SGLC; (b) report the therapy for the initial supraglottic cancer; and (c) use time-to-event analysis of its results. Six studies were eventually identified and systematically reviewed.

RESULTS

All studies included in the systematic review were retrospective (n=792 patients). The survival (overall, disease-specific and neck disease-free) and the site of neck recurrence of the patients with N0 supraglottic cancer were not significantly different between patients in the neck dissection treatment group and those of the rest of the therapeutic strategies examined (neck radiotherapy, combined therapy and 'wait and see' policy).

CONCLUSIONS

The present systematic review highlights the need for further well-designed prospective studies that will provide more reliable answers to the debatable issue of the management of cN0 of SGLC. Currently, based on the best available evidence, it seems that neck dissection is not superior to radiotherapy or combined therapy or a 'wait and see' policy in terms of survival and control of neck disease.

Preliminary multi-institutional prospective pathologic and molecular studies support preservation of sublevel IIB and level IV for laryngeal squamous carcinoma with clinically negative neck

Level II-IV selective neck dissection, often performed bilaterally, has become the procedure of choice for elective dissection of the clinically negative (N0) neck in the treatment of laryngeal cancer. The most significant morbidity of this procedure is dysfunction of the accessory nerve, incurred by the necessity of mobilization and retraction of the nerve in order to remove the contents of sublevel IIB. Other morbidity includes possible injury to the phrenic nerve and chylous fistula. These complications are associated with the dissection of level IV. A number of prospective multi-institutional studies of the distribution of cervical lymph node metastases in the neck indicate that lymph nodes in sublevel IIB and level IV are rarely involved in cases of laryngeal cancer with N0 neck. Information was obtained by the study of neck dissection specimens by conventional light microscopy, and by molecular analysis of the specimens. Molecular analysis reveals a significant number of metastases that are not discovered by light microscopy, and is thus essential for this type of evaluation. The authors conclude that these preliminary studies indicate that it is safe and appropriate to eliminate dissection of sublevel IIB and level IV from the elective neck dissection performed for laryngeal cancer with N0 neck. This practice will reduce both operating time and morbidity, particularly accessory nerve dysfunction, without compromising the oncologic result. Further prospective studies are needed to confirm these conclusions.

Neck dissection: then and now

The significance of metastatic disease in the lymph nodes of the neck as a critical independent prognostic factor in head and neck cancer has long been appreciated. Although 19th century surgeons attempted to remove involved cervical lymph nodes at the time of resection of the primary cancer, a systematic approach to en bloc removal of cervical lymph node disease, described in detail by Jawdyński in 1888 and popularized and illustrated by Crile in the early 20th century, provided consistent and more effective treatment, and forms the basis of our current techniques. During the first half of the 20th century, developments included preservation of the accessory nerve in selected cases, elective neck dissection performed in association with resection of various primary tumors, bilateral neck dissection and limited neck dissection. The greatest impetus to the status of radical neck dissection came from Martin, whose technique consisted of resection of all lymph nodes from level I-V together with the accessory nerve, internal jugular vein, sternocleidomastoid muscle and various other structures in a single block of resected tissue. Martin's technical precepts were followed until the latter part of the 20th century when modifications in technique began to find general acceptance. The first description of an effective technique of modified radical neck dissection was published in Spanish by Suárez, in 1963. This technique, which preserves important structures, such as the internal jugular vein, sternocleidomastoid muscle and accessory nerve, was refined and popularized by various authors who published their results in the English language literature during the period from 1964 through 1990 and beyond. Modified or "functional" neck dissection avoids much of the morbidity of radical neck dissection while achieving equivalent degrees of control of regional disease in properly selected cases. By the late 20th century, the concept of selective neck dissection, consisting of resection of only the nodal groups at greatest risk for metastasis from a given primary site, was studied and developed. These limited dissections are now widely employed for elective, and in properly selected cases, therapeutic treatment and staging of the neck, and have been proposed for limited cervical recurrences after various chemoradiation protocols. Prospective studies have demonstrated similar rates of neck recurrence and survival after elective selective neck dissection compared to elective modified radical neck dissection. Other modifications and factors applied to treatment of cervical lymph node disease include the use of adjuvant and neo-adjuvant radiation and chemotherapy, a revised system for classification of neck dissections, the identification of various adverse prognostic factors such as extracapsular spread and extranodal soft tissue deposits, application of sentinel lymph node biopsy to staging of the neck, the use of immunohistochemical and molecular techniques for identification of lymph node metastases not detectable by light microscopy, and the possibility of endoscopic neck dissection. The authors conclude that neck dissection, as evolved over the past century, is a fundamental tool in management of patients with head and neck cancer, but is still a work in progress.