Diagnostic and treatment modalities for patients with cervical lymph node metastases of unknown primary site - current status and challenges

[Cervical CUP Syndrome: Diagnosis and Therapy]

In CUP syndrome (CUP = cancer of unknown primary) there are 1 or more metastases of a primary tumor that cannot be localized despite extensive diagnostics. CUP syndrome accounts for 5% of all human malignancies, making it one of the 10 most common forms of cancer. In addition to inflammatory lymph node enlargement and benign changes such as cervical cysts, lymph node metastases are among the most common cervical masses. Cervical CUP syndrome is a histologically confirmed cervical lymph node metastasis with an unknown primary tumor. In addition to anamnesis, clinical examination and histological confirmation, diagnostics include radiological imaging using PET-CT and panendoscopy with histological primary tumor search. Treatment options include surgical therapy with neck dissection and chemoradiotherapy.

Is bilateral radiotherapy necessary for patients with unilateral squamous cell carcinoma of unknown primary of the head and neck region?

Background and Purpose

Squamous cell carcinoma of unknown primary (SCC-CUP) of the head and neck region remains a clinical challenge, with uncertainty surrounding the necessity of contralateral irradiation of cervical lymphatic drainage in cases of unilateral involvement.

Materials and Methods

A retrospective study was conducted at the Department of Radiation Oncology, University Medical Center Mainz, on a cohort of 50 patients with unilateral SCC-CUP of the head and neck region treated between 2005 and 2019. 30 patients received bilateral and 20 received unilateral cervical radiotherapy. The majority (n = 38, 76 %) were treated with modern IMRT/ VMAT (Intensity-modulated Radiation Therapy/ Volumetric Modulated Arc Therapy) techniques.

Results

After a median follow-up of 64.5 months, locoregional recurrences occurred in 26 % of cases (n = 13/50), all of which were ipsilateral and predominantly within the volume of the previous irradiated CTV (clinical target volume) (85 %, n = 11/13). No patient treated unilaterally developed a contralateral recurrence in the neck. After 3 years, we observed 7 locoregional recurrences in the bilateral irradiated group (n = 7/30, 23 %), and 5 locoregional recurrences in the unilateral irradiated group (n = 5/20, 25 %). After 3 years, 12 patients had died in the bilateral irradiated group (n = 12/30, 40 %), and 7 in the unilateral irradiated group (n = 7/20, 35 %). 7 Patients showed distant metastases after 3 years in the bilateral irradiated group (n = 7/30, 23 %), and 2 in the unilateral irradiated group (n = 2/20, 10 %). Locoregional control (LRC) at 5 years was 66.2 % in the bilaterally irradiated group, and 70.0 % in the unilaterally irradiated group. Overall survival (OS) was 52.6 % (bilateral) and 64.0 % (unilateral). Distant metastasis-free survival (DMFS) was 74.7 % (bilateral) and 84.4 % (unilateral). No significant differences were observed in OS (p = 0.37), LRC (p = 0.91), and DMFS (p = 0.91) between the groups.Acute toxicity ≥ °2 accordingly CTCAE (Common Terminology Criteria of Adverse Events) was high with 97% while late toxicity ≥ °2 was moderate with 31%. There was no statistically significant difference between the group of unilateral and bilateral irradiated patients.

Conclusion

These data suggest that contralateral cervical irradiation may be of limited benefit in patients with SCC-CUP, as recurrences occured ipsilaterally, and predominantly within the area of prior irradiation. Unilateral irradiation seems to be adequate for carefully selected patients.

Laterocervical lymph node metastases from suspected thyroidal primary site that turned out to be metastases of lung cancer: A case report

Incidental sonographic discovery of thyroid nodules is an increasingly common event in clinical practice. Less frequently, patients with cytological benign thyroid nodules have suspicious cervical lymph nodes detected by ultrasound examination or by cytological exam. Here, we discuss an intriguing case of cervical lymph node metastasis with a probable thyroid origin in a 65-year-old asymptomatic male smoker. He underwent thyroidectomy and unilateral cervical lymphadenectomy. Despite a negative chest X-ray, the postoperative histological examination revealed that the lymph node metastasis was actually from a lung carcinoma. Metastatic lesions in cervical lymph nodes from non-thyroidal origins must be excluded when evaluating lesions in the region, especially when thyroid nodules subjected to fine needle aspiration biopsy yield negative results, or lymph node cytological evaluations are inconsistent with thyroid cytological findings and sonographic features. Thyroid and lung adenocarcinomas share some epithelial and mesenchymal markers. Thyroglobulin helps differentiate primary thyroid tumors from lung ones, but in cases of poor differentiation, distinguishing metastatic lesions in the thyroid gland can be challenging. Lung cancer (LC) is the leading cause of cancer mortality worldwide, and survival rates have only marginally improved over the last several decades. The ongoing clinical challenge is detecting LC at earlier stages of the disease.

Comparison of PD-L1 expression in squamous cell cancer of unknown primary and oropharyngeal squamous cell carcinoma

PURPOSE

The tumorigenesis of squamous cell cancer of unknown primary (SCCUP) in the head and neck area has not been decoded so far, while poor survival rates and limited therapeutic options pose a serious challenge. The aim of this project was to investigate immunological characteristics of SCCUPs and compare them to oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

PD-L1 expression (TC) was examined by immunohistochemistry in 50 lymph node metastases of SCCUP and 47 primaries of OPSCC. CD3 + and CD8 + lymphocytic infiltration was measured in 5 high power fields. Expression of p16 and HPV ISH were assessed.

RESULTS

SCCUP demonstrated a significantly higher expression of PD-L1 than OPSCC. In p16-negative SCCUPs PD-L1 proved to be an independent prognostic factor to prioritize high-risk patients.

CONCLUSIONS

Immunologic differences between SCCUP and OPSCC were detected. A higher PD-L1 expression in SCCUP could potentially facilitate further evaluation of checkpoint inhibitor therapy.

Radiomics analysis for differentiating of cervical lymphadenopathy between cancer of unknown primary and malignant lymphoma on unenhanced computed tomography

To investigate the usefulness of texture analysis to discriminate between cervical lymph node (LN) metastasis from cancer of unknown primary (CUP) and cervical LN involvement of malignant lymphoma (ML) on unenhanced computed tomography (CT). Cervical LN metastases in 17 patients with CUP and cervical LN involvement in 17 patients with ML were assessed by ¹⁸F-FDG PET/CT. The texture features were obtained in the total cross-sectional area (CSA) of the targeted LN, following the contour of the largest cervical LN on unenhanced CT. Values for the max standardized uptake value (SUVmax) and the mean SUV value (SUVmean), and 34 texture features were compared using a Mann-Whitney U test. The diagnostic accuracy and area under the curve (AUC) of the combination of the texture features were evaluated by support vector machine (SVM) with nested cross-validation. The SUVmax and SUVmean did not differ significantly between cervical LN metastases from CUP and cervical LN involvement from ML. However, significant differences of 9 texture features of the total CSA were observed (p = 0.001 - 0.05). The best AUC value of 0.851 for the texture feature of the total CSA were obtained from the correlation in the gray-level co-occurrence matrix features. SVM had the best AUC and diagnostic accuracy of 0.930 and 84.8%. Radiomics analysis appears to be useful for differentiating cervical LN metastasis from CUP and cervical LN involvement of ML on unenhanced CT.

Carcinoma of Unknown Primary (CUP) versus CUP Turned to Primary Carcinoma of the Head and Neck—An Analysis of Diagnostic Methods and the Impact of Primary Tumor on Clinical Outcome

Background. The purpose of this study was to analyze the value of different diagnostic methods in detecting the primary site and the impact of primary tumors on the clinical outcome of carcinoma of unknown primary (CUP). Methods. In this multicenter, retrospective study, 124 patients with true CUP (n = 94) and CUP turned to primary carcinoma (n = 30) were included. Patients with evidence of primary site during the clinical examination were excluded a priori. The diagnostic procedure was comprised of imaging and invasive methods (fine-needle-aspiration, tonsillectomy and panendoscopy). All patients were treated with curative intent. Results. Despite extensive diagnostic workup, the primary site remained unknown in 75.8%. Invasive diagnostic methods showed higher primary detection rates than imaging modalities (15.1% vs. 7.8%). Tonsillectomy and panendoscopy revealed the primary tumor in 14.9% and 15.2% of patients, whereas the detection rates of CT, MRI and FDG-PET-CT were 10.1%, 4.8% and 6.5%, respectively. The occurrence of primary tumors led to a significantly deteriorating 5-year overall survival (p = 0.002) and emerged as survival prognosticator (HR = 2.764, p = 0.003). Conclusion. Clinical examination in combination with tonsillectomy and panendoscopy was superior to imaging alone in detecting the primary tumor. When the CUP of patients turned to a primary tumor, clinical outcome was significantly worse than in CUP patients.

Comparison of Ultrasound-Guided Core Needle Biopsy Under the Assistance of Hydrodissection With Fine Needle Aspiration in the Diagnosis of High-Risk Cervical Lymph Nodes: A Randomized Controlled Trial

A randomized comparison of ultrasound (US)-guided core needle biopsy (CNB) under the assistance of hydrodissection with fine needle aspiration (FNA) was performed to evaluate the feasibility, safety and effectiveness for the diagnosis of high-risk cervical lymph nodes. Patients from December 2018 to May 2020 were randomly assigned to the CNB group and the FNA group at a ratio of 1:1. This study protocol was approved by the Ethics Committee of our hospital and registered in the Chinese Clinical Trial Registry (ChiCTR1800019370). The feasibility of CNB for high-risk cervical lymph nodes was evaluated by observing and recording the separation success rate (SSR) and technical success rate (TSR) of the CNB group. Safety was evaluated by comparing the incidence of major complications in the two groups. The diagnostic efficacy was evaluated by comparing the diagnostic accuracy, sensitivity, and specificity of the two groups. A total of 84 patients (84 lymph nodes) were randomized into the CNB (n = 42) and FNA (n = 42) groups. All patients in the CNB group achieved successful hydrodissection and biopsy. The SSR and TSR were both 100% in the CNB group. There were no major complications during or after the process in the two groups. Compared with the FNA group, the CNB group was significantly superior in terms of diagnostic accuracy and sensitivity (100% vs. 81.0%, P = 0.009; 100% vs. 79.2%, P = 0.035, respectively). The specificity of the two groups was 100%, and there was no significant difference. Compared with FNA, CNB under the assistance of hydrodissection is a feasible and safe method but is more effective for the diagnosis of high-risk cervical lymph nodes.

Machine Learning Models Predict the Primary Sites of Head and Neck Squamous Cell Carcinoma Metastases Based on DNA Methylation

In head and neck squamous cell cancers (HNSCs) that present as metastases with an unknown primary (HNSC-CUPs), the identification of a primary tumor improves therapy options and increases patient survival. However, the currently available diagnostic methods are laborious and do not offer a sufficient detection rate. Predictive machine learning models based on DNA methylation profiles have recently emerged as a promising technique for tumor classification. We applied this technique to HNSC to develop a tool that can improve the diagnostic workup for HNSC-CUPs. On a reference cohort of 405 primary HNSC samples, we developed four classifiers based on different machine learning models (random forest (RF), neural network (NN), elastic net penalized logistic regression (LOGREG), support vector machine (SVM)) that predict the primary site of HNSC tumors from their DNA methylation profile. The classifiers achieved high classification accuracies (RF=83%, NN=88%, LOGREG=SVM=89%) on an independent cohort of 64 HNSC metastases. Further, the NN, LOGREG, and SVM models significantly outperformed p16 status as a marker for an origin in the oropharynx. In conclusion, the DNA methylation profiles of HNSC metastases are characteristic for their primary sites and the classifiers developed in this study, which are made available to the scientific community, can provide valuable information to guide the diagnostic workup of HNSC-CUP. This article is protected by copyright. All rights reserved.

A Systematic Review of Cancer of Unknown Primary in the Head and Neck Region

Background

Despite the vivid progress in molecular and genetic profiling, extensive diagnosis and multiple therapeutic modalities, cancers of unknown primary in the head and neck region continue to be a formidable challenge.

Aim

The purpose of the review is to present the most recent and well-established findings concerning cancers of unknown primary (CUPs) in the head and neck patients and consequently to provide medical specialists with essential information regarding the biology, pathology, histology, diagnosis and treatment of CUP in the head and neck region.

Material and Methods

The Medline/PubMed database was searched by using the following keywords “CUP”, “cancer of unknown primary”, “CUP biology”, “head and neck”. The references of the publications of interest were also screened for relevant papers. There were no limitations in regard to the publication date.

Conclusion

Unique biology and pathophysiology prompt the management of CUP to be demanding. The vivid rise in HPV-related CUPs during the last 20 years has put more focus on this phenomenon. New findings concerning the enigmatic biology of CUP provide fundaments for targeted therapy. Despite the availability of various diagnostic methods, the diagnosis of CUP continues to be a time-consuming, strenuous process that eventually provides answers. It remains controversial as to what combination of treatment methods is the most effective. There is no consensus on the value of combining chemotherapy with radiotherapy. Highly specific surgical treatments for particular histological types of CUP produce more satisfactory results. It is paramount to establish reliable guidelines concerning the diagnosis and treatment of CUP patients.

Standardized Diagnostics Including PET-CT Imaging, Bilateral Tonsillectomy and Neck Dissection Followed by Risk-Adapted Post-Operative Treatment Favoring Radio-Chemotherapy Improve Survival of Neck Squamous Cell Carcinoma of Unknown Primary Patients

BACKGROUND

About five to 10% of cancers in the head and neck region are neck squamous cell carcinoma of unknown primary (NSCCUP). Their diagnosis and treatment are challenging given the risk of missing occult tumors and potential relapse. Recently, we described human papillomavirus (HPV)-related NSCCUP-patients (NSCCUP-P) as a subgroup with superior survival. However, standardized diagnostic workup, novel diagnostic procedures, decision-making in the multidisciplinary tumor board (MDTB) and multimodal therapy including surgery and post-operative radio-chemotherapy (PORCT) may also improve survival.

METHODS

For assessing the impact of standardized diagnostic processes simultaneously established with the MDTB on outcome, we split our sample of 115 NSCCUP-P into two cohorts treated with curative intent from 1988 to 2006 (cohort 1; n = 53) and 2007 to 2018 (cohort 2; n = 62). We compared diagnostic processes and utilized treatment modalities applying Chi-square tests, and outcome by Kaplan-Meier plots and Cox regression.

RESULTS

In cohort 2, the standardized processes (regular use of [18F]-FDG-PET-CT imaging followed by examination under anesthesia, EUA, bilateral tonsillectomy and neck dissection, ND, at least of the affected site) improved detection of primaries (P = 0.026) mostly located in the oropharynx (P = 0.001). From 66.0 to 87.1% increased ND frequency (P = 0.007) increased the detection of extracapsular extension of neck nodes (ECE+) forcing risk factor-adapted treatment by increased utilization of cisplatin-based PORCT that improved 5-years progression-free and overall survival from 60.4 and 45.3 to 67.7% (P = 0.411) and 66.1% (P = 0.025).

CONCLUSIONS

Standardized diagnostic workup followed by ND and risk-factor adapted therapy improves survival of NSCCUP-P.

The Role of 18F-FDG PET/CT for Evaluation of Cervical Metastatic Lymph Nodes in a Patient with Metallic Artifacts from Dental Prosthesis: a Case Report

Cervical metastasis of squamous cell carcinoma from an unknown primary site occurs in approximately 2-4% of head and neck tumor cases. Without identification of the primary site, proper management cannot be achieved, resulting in significant morbidity and a lower cure rate. For the primary site assessment, positron emission tomography/computed tomography (PET/CT) using the radiotracer ¹⁸F-fluorodeoxyglucose (FDG) is the imaging modality of choice and has been shown to be superior to CT alone. Here, we report a case of cervical metastasis of squamous cell carcinoma in an 82-year-old man. ¹⁸F-FDG PET/CT revealed a tongue-base lesion, although neck CT detected no lesions because of artifacts from dental prosthesis, which was suspected as the primary site. The final diagnosis was confirmed as tongue-base cancer with neck lymph node metastases through biopsy. These results suggest that ¹⁸F-FDG PET/CT is a valuable diagnostic tool in patients with cervical metastatic lymph nodes because it can demonstrate primary tumors in patients with dental prosthesis.

Diagnosis and Management of Squamous Cell Carcinoma of Unknown Primary in the Head and Neck: ASCO Guideline

PURPOSE

To provide evidence-based recommendations to practicing physicians and other health care providers on the diagnosis and management of squamous cell carcinoma of unknown primary in the head and neck (SCCUP).

METHODS

The American Society of Clinical Oncology convened an Expert Panel of medical oncology, surgery, radiation oncology, radiology, pathology, and advocacy experts to conduct a literature search, which included systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 2008 through 2019. Outcomes of interest included survival, local and regional disease control, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 100 relevant studies to inform the evidence base for this guideline. Four main clinical questions were addressed, which included subquestions on preoperative evaluations, surgical diagnostic and therapeutic procedures, appropriate pathology techniques, and adjuvant therapy.

RECOMMENDATIONS

Evidence-based recommendations were developed to address preoperative evaluation for patients with a neck mass, surgical diagnostic and therapeutic procedures, appropriate treatment options in unilateral versus bilateral SCCUP.Additional information is available at www.asco.org/head-neck-cancer-guidelines.

Radiotherapeutic management of cervical lymph node metastases from an unknown primary site - experiences from a large cohort treated with modern radiation techniques

Purpose

To analyze management and outcomes following (chemo)radiation therapy in patients with cervical lymph node metastases from an unknown primary site (CCUP) in a large single-center cohort.

Methods

Between 2008 and 2019, 58 patients with CCUP were treated with (chemo)radiation therapy at the University of Freiburg Medical Center and were included in this analysis. Overall survival (OS), locoregional progression-free survival (PFS) and distant metastasis-free survival (DMFS) were calculated using the Kaplan-Meier method. The use of diagnostic procedures and their impact on oncological outcomes was analyzed by Cox regression, and treatment-related toxicities were quantified.

Results

Median follow-up was 29.9 months (range 4.6–121.9). Twenty-one patients (36.2%) received definitive RT, 35 (60.3%) underwent adjuvant RT, and 2 (3.4%) were treated for oligometastatic disease. Concurrent chemotherapy was prescribed in 40 patients (69.0%). 89.6% of patients completed the prescribed RT, and 65.0% completed the prescribed simultaneous chemotherapy. Locoregional recurrence was observed in 7 patients (12.1%) and distant metastases in 13 cases (22.4%). OS was 81,1, 64.9% and 56,6% after 1, 3 and 5 years, respectively.

Univariate analysis of age, gender, extracapsular spread, tumor grading, neck dissection, diagnostic utilization of ¹⁸F-fluorodeoxyglucose positron-emission tomography and concomitant chemotherapy showed no effect on OS (p > 0.05 for all), while smoking was significantly associated with decreased survival (p < 0.05). There was a trend towards impaired OS for patients with advanced nodal status (pN3) (p = 0.07). Three patients (5.2%) experienced grade 3 radiation dermatitis, and 12 (22.4%) developed grade 3 and 1 (1.7%) grade 4 mucositis.

Conclusions

RT of the panpharynx and cervical lymph nodes with concurrent chemotherapy in case of risk factors demonstrated good locoregional control, but the metachronous occurrence of distant metastases limited survival and must be further addressed.

Evaluation of radiation treatment volumes for unknown primaries of the head and neck in the era of FDG PET

Objectives

Positron-emission tomography (PET) has improved identification of the primary tumor as well as occult nodal burden in cancer of the head and neck. Nevertheless, there are still patients where the primary tumor cannot be located. In these situations, the standard of care is comprehensive head and neck radiation therapy however it is unclear whether this is necessary. This study examines the effects of radiation treatment volume on outcomes among using data from two cancer centers in unknown primary carcinoma of the head and neck.

Methods

Patients received unilateral (n = 34), or bilateral radiation (n = 28). Patient factors such as age, gender, smoking history, and patterns of failure were compared using Mann Whitney U and Chi Square. Overall survival (OS) and disease free survival (DFS) trends were estimated using Kaplan-Meier survival curves. Effect of treatment volume on survival was examined using multivariate cox proportional hazard regression model.

Results

No significant differences were observed in the frequency of local (p = 0.32), regional (p = 0.50), or distant (p = 0.76) failures between unilateral and bilateral radiation therapy. By Kaplan-Meier estimates, OS (3-year OS bilateral = 71.67%, unilateral = 77.90%, p = 0.50) and DFS (3-year DFS bilateral = 77.92%, unilateral = 69.43%, p = 0.63) were similar between the two treatment approaches. Lastly, multivariate analysis did not demonstrate any significant differences in outcome by treatment volumes (OS: HR = 0.74, 95% CI: 0.31, 1.81, p = 0.51; DFS: HR: 0.68, 95% CI: 0.24, 1.93, p = 0.47).

Conclusions

Unilateral radiation therapy compared with bilateral produced similar survival.

Failure patterns of cervical lymph nodes in metastases of unknown origin according to target volume

Purpose

This study was aim to evaluate the patterns of failure according to radiotherapy (RT) target volume for cervical lymph nodes in metastases of unknown primary origin in head and neck region (HNMUO).

Materials and Methods

Sixty-two patients with HNMUO between 1998 and 2016 were retrospectively reviewed. We analyzed the clinical outcomes and primary site failure depending on the radiation target volume. The target volume was classified according to whether the potential head and neck mucosal sites were included and whether the neck node was treated involved side only or bilaterally.

Results

Potential mucosal site RT (mucosal RT) was done to 23 patients and 39 patients did not receive mucosal RT. Mucosal RT showed no significant effect on overall survival (OS) and locoregional recurrence (LRR). The location of primary site failure encountered during follow-up period was found to be unpredictable and 75% of patients with recurrence received successful salvage therapies. No significant differences in OS and LRR were found between patients treated to unilateral (n = 35) and bilateral neck irradiation (n = 21). Treatment of both necks resulted in significantly higher mucositis.

conclusions

We found no advantages in OS and LRR of patients with HNMUO when mucosal sites and bilateral neck node were included in the radiation target volume.

Current role of primary surgical treatment in patients with head and neck squamous cell carcinoma

PURPOSE OF REVIEW

The objective of this review article is to discuss the current role of surgery as the primary treatment modality in patients with head and neck squamous cell carcinoma (HNSCC).

RECENT FINDINGS

HNSCC represents one of the cancer locations where the primary treatment modality is the most under discussion. Indeed, the respective roles of primary surgical resection followed, as necessary, by adjuvant radiotherapy or definitive chemoradiotherapy remain controversial. The results of organ preservation trials and the drastic rise in the incidence of human papillomavirus-induced oropharyngeal tumors, which are known to be highly radiosensitive, have led to an increasing use of chemoradiation-based therapies in HNSCC patients. However, no chemoradiation-based protocol has shown better oncologic outcomes than radical primary surgery. Moreover, development of minimally invasive surgical techniques, such as transoral robotic surgery, and advances in head and neck microvascular reconstruction have considerably improved the clinical outcomes of the patients and have led to a reconsideration of the role of primary surgery in HNSCC patients.

SUMMARY

Surgery should be the primary treatment modality for most resectable oral cavity cancers and for T4a laryngeal/hypopharyngeal cancers. Primary surgery could also be the preferred modality of treatment for most early (T1-T2, N0) laryngeal and hypo/oropharyngeal carcinomas when this strategy offers an opportunity to reserve radiotherapy for a potential recurrence or second primary tumor. Primary surgery should also be considered in patients with locally advanced human papillomavirus-negative oropharyngeal carcinoma.

Tumor control of cervical lymph node metastases of unknown primary origin: the impact of the radiotherapy target volume

PURPOSE

Debate on the extent of treatment of neck metastasis of cancer of unknown primary tumors (CUPs) is still ongoing. In two Dutch tertiary referral centers, the post-surgical radiation target volume changed from the bilateral neck including the pharyngeal axis to the unilateral neck only, in the course of the last decade. This study aims to investigate the outcome of patients with CUP before and after de-escalation of post-surgical radiotherapy.

METHODS

Data of two Dutch tertiary referral centers were merged. Disease-free survival (DFS), overall survival (OS), and regional control rate (RCR) of 80 patients diagnosed with CUP (squamous cell and undifferentiated carcinomas) between 1990 and 2009 were retrospectively analyzed.

RESULTS

Thirty patients received bilateral neck and pharyngeal axis radiotherapy and 42 patients ipsilateral radiotherapy only. In another eight patients, the postsurgical radiation target volume was expanded to the contralateral neck or to the pharyngeal axis, due to suspicious lesions on imaging. The 5-year DFS, OS and RCR were 60%, 51.2%, and 80%, respectively, in the total patient population. RCR did not differ in patients treated with ipsilateral as compared to bilateral radiotherapy nor did 5-year OS and DFS. No tumors occurred in the pharyngeal axis.

CONCLUSION

In this study, omitting elective treatment of the contralateral neck and pharyngeal axis did not lead to a decrease in locoregional control or survival rates when treating patients with CUP.

PET/CT Evaluation of Head and Neck Cancer of Unknown Primary

The diagnosis of carcinoma of unknown primary in the head and neck is made when there is a metastasis but no primary lesion is identified after physical exam and diagnostic CT or MR imaging. PET/CT is the first step in searching for a primary lesion, followed by more invasive techniques such as endoscopy and surgery. Knowledge of the different tumor histologic types, preferential locations of nodal spread, imaging pitfalls, and other special considerations such as cystic metastases can be helpful in the ultimate identification of primary tumors, which leads to improved overall patient survival.

[Neck dissection-Surgical treatment of cervical lymphatic drainage pathways]

Neck dissection (ND) is an essential component of treatment in head and neck squamous cell carcinoma (HNSCC). The extent of ND depends on primary tumor location and T and N stage. Trials have demonstrated improved survival for cN+ status with therapeutic ND as well as for cN0 status with selective ND if the primary has a high incidence of occult metastasis. The accuracy of the procedure is of prognostic relevance. In the prognostic model of the TNM classification, the parameter "N" does not only reflect the number of affected lymph nodes, but also their size and extranodal tumor extension. Due to its better prognosis, a positive human papillomavirus (HPV) status is also incorporated in the present TNM classification. In order to minimize morbidity after ND, one seeks to limit its extent without reducing survival time. To this aim, sentinel node biopsy or surveillance with positron-emission computed tomography (PET-CT) in cN0 necks or after primary radio(chemo)therapy are being investigated.

US-guided core needle biopsy under assistance of hydrodissection to diagnose small lymph node metastases adjacent to cervical large vessels

PURPOSE

We aimed to evaluate the safety and effectiveness of ultrasonography (US) guided core needle biopsy (CNB) with hydrodissection to diagnose small lymph node metastases adjacent to cervical large vessels.

METHODS

From January 2013 to October 2017, 31 patients with 31 cervical lymph node metastases adjacent to large vessels presented for US-guided CNB. The mean maximal diameter of lymph nodes was 0.93±0.16 cm (range, 0.6-1.2 cm). All patients underwent US-guided CNB with 18-gauge true-cut biopsy needle after hydrodissection with saline. The separation success rate (SSR) of the hydrodissection, technical success rate (TSR) of CNB, histopathologic success rate (HST), and complications were assessed.

RESULTS

The SSR of hydrodissection was 100% (31/31). After effective separation between the lymph node metastases and the adjacent large vessels with saline injection, the procedures of CNB were performed with a TSR of 100% (31/31). The HST of the lymph node metastases was 100% (31/31). Two patients complained of mild cervical swelling sensation during saline injection. No major complications such as injury of the large vessels or massive hemorrhage occurred.

CONCLUSION

Hydrodissection can facilitate safely and effectively US-guided CNB of subcentimeter cervical lymph nodes adjacent to large vessels, potentially impacting further therapeutic decisions.

Inter-observer variability of clinical target volume delineation in definitive radiotherapy of neck lymph node metastases from unknown primary. A cooperative study of the Italian Association of Radiotherapy and Clinical Oncology (AIRO) Head and Neck Group

BACKGROUND

This study, promoted by Italian Association of Radiotherapy and Clinical Oncology (AIRO) Head and Neck Group, aimed to assess the current national practice of target volume delineation on a case of neck lymph node metastases from unknown primary evaluating inter-observer variability, in a setting of primary radiotherapy.

MATERIALS AND METHODS

A case of metastatic neck lymph node from occult primary was proposed to 17 radiation oncologists. A national reference RT center was identified and considered as benchmark. Participants were requested to delineate target volumes. A structured questionnaire was administered. A comparison between following parameters of the CTVs was performed: centroids distances, Dice similarity index (DSI), Jaccard index and mean distance to agreement (MDA). Volume expressed in cubic centimeters and CTVs cranio-caudal extension were evaluated.

RESULTS

Sixteen of 17 radiation oncologists recommended three CTVs dose levels. (CTV HD, CTV ID and CTV LD); CTV ID was not delineated by one of the participants and by the reference center. The distance between the reference centroid and the mean centroid of CTVs HD was 1.09 cm (0.36-3.99 cm); for CTV LD, a mean centroids distance of 2.45 (0.27-4.83 cm) was found, and for CTV HD, mean DSI is 0.48 and mean Jaccard index is 0.32 and MDA was 8.89 mm. CTV LD showed a mean DSI of 0.46, mean Jaccard index of 0.31 and MDA of 14.87 when compared to the reference.

CONCLUSION

Many aspects concerning treatment optimization of cervical nodes metastases from occult primary remain unclear, and we found a notable heterogeneity of global radiotherapy management reporting discordances both in target volume delineation and volume prescription.

Combination of panendoscopy and positron emission tomography/computed tomography increases detection of unknown primary head and neck carcinoma

OBJECTIVES/HYPOTHESIS

With positron emission tomography/computed tomography (PET/CT) now commonplace as a diagnostic tool, new questions have arisen regarding the utility and cost-effectiveness of panendoscopy. In this retrospective review of a large cohort of head and neck squamous cell carcinoma of unknown primary (HNSCC-UP), we describe the enduring utility of panendoscopy in the detection of the primary site of mucosal disease even when PET/CT is negative.

STUDY DESIGN

Retrospective cohort study.

METHODS

A retrospective analysis of patients presenting to the senior author (y.d.) from July 1 1997 to July 1 2017 with fine-needle aspiration-proven metastatic squamous cell carcinoma to the neck. All patients underwent formal panendoscopy (direct laryngoscopy, bronchoscopy, and rigid esophagoscopy). Presence of squamous cell carcinoma on final pathology was examined.

RESULTS

A total of 190 patients had HNSCC-UP, with 87 positive and 103 negative on PET/CT. Of the PET/CT-negative patients, 71 patients retained the HNSCC-UP designation after panendoscopy. Eighteen patients (56% of cases) were found to have primary tonsillar squamous cell carcinoma. Eight of 32 primary sites were found in the base of tongue (25%), with HPV positivity in two of these patients. The sensitivity and negative predictive value of PET/CT in detecting the primary site in unknown primary head and neck squamous cell carcinoma in the total study population were 73.1% and 68.9%, respectively.

CONCLUSIONS

Surgical panendoscopy has an important role in the workup of patients with unknown primary head and neck squamous cell carcinoma. There is a high rate of cancer diagnosis, even in PET/CT negative patients.

LEVEL OF EVIDENCE

4 Laryngoscope, 2573-2575, 2018.

GEORCC recommendations on target volumes in radiotherapy for Head Neck Cancer of Unkown Primary

Head Neck Cancer of Unknown Primary (HNCUP) is a rare condition, representing approximately 5-10% of all head neck cancers. Radiotherapy, adjuvant or radical, is usually employed in the treatment of those patients. To date, no specific guidelines for the optimal definition of the target volume to be irradiated have been published. In recent years, there have been advances in the knowledge of the molecular biology of HNCUP, its diagnostic imaging and the implementation of sophisticated radiotherapy techniques with enhanced precision in target localization and treatment delivery. These progresses have provided valuable information about the natural history of HNCUP that will allow for establishment of the best treatment for each patient, including standardized, consistent and reproducible target volumes definitions. Several recommendations regarding how to choose volumes when contouring HNCUP in clinical practice are reported, in order to achieve a high rate of loco-regional control while avoiding unnecessary toxicity.