Contemporary management of lymph node metastases from an unknown primary to the neck: I. A review of diagnostic approaches

Swallowing outcomes after transoral robotic surgery and adjuvant treatment in unknown primary

OBJECTIVES

Robotic transoral mucosectomy of the base of tongue was introduced as a diagnostic procedure in patients treated for head and neck cancer with unknown primary (CUP), increasing the identification rate of the primary tumour. For the treatment of CUP, a considerable percentage of patients require adjuvant (chemo)radiation. The aim of this study was to investigate swallowing outcomes among CUP patients after TORS and adjuvant treatment.

SUBJECTS AND METHODS

A systematic review was carried out on studies investigating the impact of TORS and adjuvant treatment on swallowing-related outcomes among CUP patients In addition, a cross-sectional study was carried out on swallowing problems (measured using the SWAL-QOL questionnaire) among CUP patients in routine care who visited the outpatient clinic 1-5 years after TORS and adjuvant treatment.

RESULTS

The systematic review (6 studies; n = 98) showed that most patients returned to a full oral diet. The cross-sectional study (n = 12) showed that all patients were able to return to a full oral diet, nevertheless, 50% reported swallowing problems in daily life (SWAL-QOL total score ≥14).

CONCLUSION

Although after TORS and adjuvant treatment for CUP a full oral diet can be resumed, patients still experience problems with eating and drinking in daily life.

Primary Tumour Detection in Carcinoma of Unknown Primary with Transoral Robotic Surgery (TORS) Tongue Base Mucosectomy: A Meta-analysis

BACKGROUND

Head and neck carcinoma of unknown primary (CUP) represents a challenging diagnostic process when standard work-up fails to identify the primary tumour site. The aim of this systematic review and meta-analysis was to evaluate the diagnostic utility and complication profile of transoral robotic surgery (TORS) tongue base mucosectomy (TBM) in the management of CUP.

PATIENTS AND METHODS

An electronic database search was performed in the EMBASE, MEDLINE, PubMed and Cochrane databases. A meta-analysis of proportions was performed to obtain an estimate of the overall proportion for the detection and complication rates.

RESULTS

Nine studies representing 235 patients with CUP who had TORS TBM were included in the final analysis. The overall pooled tumour detection rate was 66.2% [95% confidence interval (CI) 56.1-75.8]. The incidence of tumour detection in human papilloma virus (HPV)-positive cases (81.5%, 95% CI 60.8-96.4) was significantly higher than HPV-negative cases (2.3%, 95% CI 0.00-45.7). Weighted overall complication rate was 11.4% (95% CI 7.2-16.2). The majority were grade I or II (80%) according to the Clavien-Dindo classification.

CONCLUSIONS

This meta-analysis suggests TORS to be safe and effective in localising the primary tumour site in patients with CUP. While the current data supports the use of TORS in patients who are HPV positive, larger numbers of HPV-negative cases are required to determine the true diagnostic effect with TORS before any valid conclusions can be inferred in this particular subgroup. Further research should focus on high quality prospective trials with stringent methodological work-up to minimise heterogeneity and allow for more accurate statistical analysis.

Head and neck cancer of unknown primary: unveiling primary tumor sites through machine learning on DNA methylation profiles

BACKGROUND

The unknown tissue of origin in head and neck cancer of unknown primary (hnCUP) leads to invasive diagnostic procedures and unspecific and potentially inefficient treatment options for patients. The most common histologic subtype, squamous cell carcinoma, can stem from various tumor primary sites, including the oral cavity, oropharynx, larynx, head and neck skin, lungs, and esophagus. DNA methylation profiles are highly tissue-specific and have been successfully used to classify tissue origin. We therefore developed a support vector machine (SVM) classifier trained with publicly available DNA methylation profiles of commonly cervically metastasizing squamous cell carcinomas (n = 1103) in order to identify the primary tissue of origin of our own cohort of squamous cell hnCUP patient's samples (n = 28). Methylation analysis was performed with Infinium MethylationEPIC v1.0 BeadChip by Illumina.

RESULTS

The SVM algorithm achieved the highest overall accuracy of tested classifiers, with 87%. Squamous cell hnCUP samples on DNA methylation level resembled squamous cell carcinomas commonly metastasizing into cervical lymph nodes. The most frequently predicted cancer localization was the oral cavity in 11 cases (39%), followed by the oropharynx and larynx (both 7, 25%), skin (2, 7%), and esophagus (1, 4%). These frequencies concord with the expected distribution of lymph node metastases in epidemiological studies.

CONCLUSIONS

On DNA methylation level, hnCUP is comparable to primary tumor tissue cancer types that commonly metastasize to cervical lymph nodes. Our SVM-based classifier can accurately predict these cancers' tissues of origin and could significantly reduce the invasiveness of hnCUP diagnostics and enable a more precise therapy after clinical validation.

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.

Utility of UV Signature Mutations in the Diagnostic Assessment of Metastatic Head and Neck Carcinomas of Unknown Primary

BACKGROUND

Metastatic carcinoma of unknown primary origin to the head and neck lymph nodes (HNCUP) engenders unique diagnostic considerations. In many cases, the detection of a high-risk human papillomavirus (HR-HPV) unearths an occult oropharyngeal squamous cell carcinoma (SCC). In metastatic HR-HPV-independent carcinomas, other primary sites should be considered, including cutaneous malignancies that can mimic HR-HPV-associated SCC. In this context, ultraviolet (UV) signature mutations, defined as ≥ 60% C→T substitutions with ≥ 5% CC→TT substitutions at dipyrimidine sites, identified in tumors arising on sun exposed areas, are an attractive and underused tool in the setting of metastatic HNCUP.

METHODS

A retrospective review of institutional records focused on cases of HR-HPV negative HNCUP was conducted. All cases were subjected to next generation sequencing analysis to assess UV signature mutations.

RESULTS

We identified 14 HR-HPV negative metastatic HNCUP to either the cervical or parotid gland lymph nodes, of which, 11 (11/14, 79%) had UV signature mutations, including 4 (4/10, 40%) p16 positive cases. All UV signature mutation positive cases had at least one significant TP53 mutation and greater than 20 unique gene mutations.

CONCLUSION

The management of metastatic cutaneous carcinomas significantly differs from other HNCUP especially metastatic HR-HPV-associated SCC; therefore, the observation of a high percentage of C→T with CC →TT substitutions should be routinely incorporated in next generation sequencing reports of HNCUP. UV mutational signatures testing is a robust diagnostic tool that can be utilized in daily clinical practice.

Extra-Capsular Spread of Lymph Node Metastasis in Oral, Oropharyngeal and Hypopharyngeal Cancer: A Comparative Subsite Analysis

BACKGROUND

The extra-capsular spread (ECS) of lymph node metastasis (LNM) is a hallmark of aggressive primary tumor phenotype in head and neck cancer (HNC); however, the factors influencing ECS are poorly understood.

PATIENTS AND METHODS

This was a retrospective study, including 190 cases of oral tongue cancer (OTC), 148 cases of oropharyngeal cancer (OPC) (118 HPV-positive and 30 HPV-negative), and 100 cases of hypopharyngeal cancer (HPC). Tumor dimension, tumor biological variables (lymphovascular/perineural invasion and histologic grade), and LNM variables (LNM number and size) were analyzed according to the presence of ECS using multivariable logistic regression and receiver operating characteristic (ROC) curve analyses.

RESULTS

LNM variables were significant factors for ECS in all subsites of HNC (p < 0.05), except HPV-positive OPC. In OTC, tumor dimensional variables were significantly related to ECS (p < 0.01). Meanwhile, in OPC and HPC, neither the primary tumor dimension nor the T status were significant factors for ECS occurrence. The predictability of ECS by ROC curve using multiple variables was 0.819 [95% confidence interval: 0.759-0.878] in OTC, 0.687 [0.559-0.815] in HPV-positive OPC, 0.823 [0.642-1.000] in HPV-negative OPC, and 0.907 [0.841-0.973] in HPC.

CONCLUSION

LNM variables were correlated with ECS occurrence for most HNC subsites, and site-dependent primary tumor characteristics might contribute differentially to the ECS development of LNM in HNC.

Stratifying risk of malignancy in cystic lateral neck lumps: a multivariant analysis of demographic, radiological and histological investigation factors and the development of a patient-centred risk-predictive tool for malignancy

BACKGROUND

Management of lateral cystic neck masses with no apparent upper aerodigestive tract primary tumour in adults is controversial. Imaging modalities and fine needle aspiration cytology often struggle to distinguish the presence of malignancy.

METHOD

This study entailed a multicentre retrospective review of all patients with isolated lateral cystic neck masses from 2012 to 2018 in three Welsh health boards, utilising demographic data and first-line investigations (ultrasound scanning and fine needle aspiration cytology) to develop an evidence-based predictive tool for risk of malignancy.

RESULTS

It was found that 29.1 per cent of cystic lesions were malignant on final histology. Age, male gender, non-benign ultrasound scan findings and fine needle aspiration cytology were significant risk factors on univariate analysis. The final multivariate analysis predicted a risk of malignancy ranging from 2.1 to 65.0 per cent depending on the covariate pattern. Smoking status was non-significant.

CONCLUSION

A rigorous, risk-stratified approach to the management of these patients should aid the clinician in minimising morbidity and optimising resources.

Pre-Existing Interstitial Lung Abnormalities in Patients with Head and Neck Squamous Cell Carcinoma and Their Follow Up after Therapy

Interstitial lung abnormalities (ILAs) are incidentally found nondependent parenchymal abnormalities affecting more than 5% of any lung zone and are potentially related to interstitial lung disease and worsening post-treatment outcomes in malignancies and infectious diseases. The aim of this study was to determine the prevalence and type of ILA changes in patients with head and neck squamous cell carcinoma (HNSCC) and their change in the follow-up period. This retrospective single-center study included 113 patients with newly diagnosed HNSCC who underwent lung MSCT prior to treatment. ILAs were reported in 13.3% of patients on pretreatment MSCT. Patients with ILAs were significantly older (median 75 vs. 67 years). ILAs were most prevalent in lower zones (73.3%) (p = 0.0045). The most reported ILA subtype was subpleural non-fibrotic (60%) (p = 0.0354). Reticulations were the most frequently described pattern (93.3%) (p < 0.0001). Progression of ILAs was reported in almost 30% of patients after receiving therapy. Patients with pre-existing ILAs were more likely to develop radiation-induced lung fibrosis after adjuvant radiotherapy (p = 0.0464). In conclusion, ILA's incidence, distribution and presentation were similar to previous research conducted in other special cohorts. Our research suggests a possible association of more frequent radiation pneumonitis with ILA changes in patients with HNSCC, which should be further investigated.

Positive factors on survival of head and neck cancer of unknown primary: what the clinician can do

BACKGROUND

Management of patients with head and neck cancer of unknown primary (HNCUP) is challenging.

AIMS/OBJECTIVES

To provide a long-term analysis focusing on protective survival factors for clinical decision-making. Furthermore, the prognostic value of the current N classification system was evaluated.

MATERIAL AND METHODS

We retrospectively analyzed patients with HNCUP between 2003 and 2016. Univariate and multivariate analyses were used to investigate predictors of overall survival (OS).

RESULTS

A primary tumor was found in 67 of 290 patients with suspected HNCUP, leaving after exclusion 141 HNCUP cases for analysis, who received multi-step therapy (MST) (n = 108) or single therapy (n = 28). Chemotherapy (CT) (n = 101), curative MST, ≤3 positive lymph nodes (LN) (n = 33), squamous cell carcinoma (SCC) (n = 123), HPV+ (n = 21), M0 (n = 70) increased OS by 21.8%, 24.4%, 12.7%, 6.8%, 18.7%, 29.6%, respectively. 5- and 10-year OS was 78.1%/66.6%. The number of metastatic LNs predicted OS is better than N classification.

CONCLUSION AND SIGNIFICANCE

Aspects for clinical decision-making: Curative MST and SCC histology were the most significant predictors for improved OS. Categorizing LN into 1, 2-3, and >3 LNs was more significant than the traditional N classification. The addition of CT to curative MST has a stronger impact on survival than HPV and N classifications.

Clinical practice guidelines for management of head and neck squamous cell carcinoma of unknown primary: an AGREE II appraisal

IMPORTANCE

Squamous cell carcinoma without a known primary is an uncommon form of head and neck cancer that requires multidisciplinary collaboration for effective management.

OBJECTIVE

To evaluate the quality of clinical practice guidelines (CPG) using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument.

DESIGN

A systematic literature search was performed to identify CPGs pertaining to the diagnosis and treatment of head and neck squamous cell carcinoma of unknown primary (HNSCCUP). Data were abstracted from guidelines meeting inclusion criteria and appraised by four independent reviewers in the six domains of quality defined by the AGREE II.

SETTING

Online database.

PARTICIPANTS

None.

EXPOSURE

None.

MAIN OUTCOME(S) AND MEASURE(S)

Quality domain scores and intraclass correlation coefficients (ICC) were calculated across domains to qualify inter-rater reliability.

RESULTS

Seven guidelines met inclusion criteria. Two guidelines achieved a score of > 60% in five or more AGREE II quality domains to gain designation as 'high'-quality content. One "average-quality" guideline authored by the ENT UK Head and Neck Society Council achieved a score of > 60% in three quality domains. The remaining four CPGs demonstrated low-quality content, with deficits most pronounced in domains 3 and 5, suggesting a lack of rigorously developed and clinically applicable information.

CONCLUSIONS AND RELEVANCE

As the diagnosis and treatment of head and neck cancer continues to evolve, identification of high-quality guidelines will become increasingly important. The authors recommend consulting HNSCCUP guidelines from the National Institute for Health and Care Excellence (NICE) or the American Society of Clinical Oncology (ASCO).

TRIAL REGISTRATION

None.

Transoral Laser Resection of the Tongue Base in the Workup of Unknown Primary Head and Neck Squamous Cell Carcinoma

Objective Failure to localize the primary tumor site in head and neck carcinoma of unknown origin after imaging and endoscopic evaluation leads to increased treatment-related morbidity. The use of transoral laser microsurgery to improve the detection of unknown primary carcinoma site identification is described in this article. Methods A retrospective cohort of 71 consecutive cases of cervical carcinoma of an unknown primary source from 2006 until 2012 from a single academic institution was analyzed. Of these, 10 patients were excluded based on our exclusion criteria. All patients underwent endoscopy with biopsies performed by fellowship-trained head and neck cancer surgeons.  Results The primary detection rate was 76% for patients who underwent laser tongue base resection versus 34% for traditional operative examination. There were no complications or prolonged recovery times in either group. Operative time was increased by the addition of the transoral base of tongue resection by 30 minutes. Conclusions Laser tongue base excision offers improved sensitivity in primary site detection without a significant increase in morbidity and only a modest increase in operative time.

Predictors for Survival of Patients with Squamous Cell Carcinoma of Unknown Primary in the Head and Neck Region

Background: Human papillomavirus (HPV) status is the most important predictor of survival in oropharyngeal squamous cell carcinoma (OPSCC). In patients with cervical lymph node metastases of squamous cell carcinoma of unknown origin (CUPHNSCC), much less is known. Methods: We assessed a consecutive cohort of CUPHNSCC diagnosed from 2000–2018 for HPV DNA, mRNA, p16INK4a (p16) expression, and risk factors to identify prognostic classification markers. Results: In 32/103 (31%) CUPHNSCC, p16 was overexpressed, and high-risk HPV DNA was detected in 18/32 (56.3%). This was mostly consistent with mRNA detection. In recursive partitioning analysis, CUPHNSCC patients were classified into three risk groups according to performance status (ECOG) and p16. Principal component analysis suggests a negative correlation of p16, HPV DNA, and gender in relation to ECOG, as well as a correlation between N stage, extranodal extension, and tobacco/alcohol consumption. Conclusions: Despite obvious differences, CUPHNSCC shares similarities in risk profile with OPSCC. However, the detection of p16 alone appears to be more suitable for the classification of CUPHNSCC than for OPSCC and, in combination with ECOG, allows stratification into three risk groups. In the future, additional factors besides p16 and ECOG may become important in larger studies or cases with special risk profiles.

The role of transoral surgery in the diagnosis of the carcinoma of unknown origin of the head and neck

PURPOSE OF REVIEW

The aim of this article is to update readers on the most recent evidence on the role of trans oral surgery (TOS) in the diagnosis of carcinoma of the unknown primary of the head and neck.

RECENT FINDINGS

Tongue base mucosectomy has an important role in identifying the primary in patients who have had negative imaging, PET CT scans and ipsilateral tonsillectomy. In patients with bilateral nodal disease, tongue base mucosectomy should precede tonsillectomy. There are several unanswered questions that remain regarding sequencing of operations and use of intraoperative frozen section.

SUMMARY

An evidence-based approach to diagnosis is important to ensure the highest detection rates, and least morbidity, in patients with head and neck carcinoma of the unknown primary.

Laser tongue base mucosectomy is a useful diagnostic tool in the management of unknown primary cancers of the head and neck region

OBJECTIVE

Tongue base mucosectomy identified cancer in 78 per cent of cancers of unknown primary in a recent meta-analysis. The carbon dioxide laser is an alternative technique if there is no access to a robot. This study aimed to describe the steps for undertaking tongue base mucosectomy using the carbon dioxide laser and its diagnostic utility in cancers of unknown primary.

METHOD

This was a prospective feasibility study utilising carbon dioxide laser for tongue base mucosectomy in cancers of unknown primary. Data collected included demographic data and p16 status.

RESULTS

There were 14 cancers of unknown primary with 86 per cent p16 positivity on immunohistochemistry. Laser tongue base mucosectomy alone identified the cancer primary in 7 of 12 (58 per cent) cancers of unknown primary among p16 positive tumours and 0 of 2 (0 per cent) among p16 negative tumours. Combining bilateral tonsillectomy with laser tongue base mucosectomy resulted in identification of the primary cancer in 8 of 12 (67 per cent) p16 positive tumours.

CONCLUSION

In centres without a robot, tongue base mucosectomy using the carbon dioxide laser is a viable alternative, especially in combination with bilateral tonsillectomy in p16 positive cases.

Imaging Approach for Cervical Lymph Node Metastases from Unknown Primary Tumor

Neck swelling due to lymph node (LN) metastasis is one of the initial symptoms of head and neck cancer, and in some cases, the primary tumor is not clinically evident. The purpose of imaging for LN metastasis from an unknown primary site is to identify the primary tumor or detect its absence, which leads to the correct diagnosis and optimal treatment. The authors discuss diagnostic imaging approaches for identifying the primary tumor in cases of unknown primary cervical LN metastases. The distribution and characteristics of LN metastases may help locate the primary site. Unknown primary LN metastasis often occurs at nodal levels II and III, and in recent reports, these were mostly related to human papillomavirus (HPV)-positive squamous cell carcinoma of the oropharynx. Another characteristic imaging finding suggestive of metastasis from HPV-associated oropharyngeal cancer is a cystic change in LN metastases. Other characteristic imaging findings such as calcification may help predict the histologic type and locate the primary site. In cases of LN metastases at nodal levels IV and VB, a primary lesion located outside the head and neck region must also be considered. One clue for detecting the primary lesion at imaging is the disruption of anatomic structures, which can help in identifying small mucosal lesions or submucosal tumors at each subsite. Additionally, fluorine 18 fluorodeoxyglucose PET/CT may help identify a primary tumor. These imaging approaches for identifying primary tumors enable prompt identification of the primary site and assist clinicians in making the correct diagnosis. ^© RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Cervical squamous cell carcinoma of unknown primary: Oncological outcomes and prognostic factors

Background/Objectives

Cervical squamous cell carcinoma of unknown primary (SCCUP) is a rare entity within head and neck cancer and both treatment regimens as well as identified potential predictors for oncological outcomes vary between published series. In this study, we evaluated oncological outcomes and identified potential prognostic factors for outcome.

Patients and methods

This retrospective monocentric cohort study includes 82 SCCUP patients diagnosed and treated between January 2000 and June 2021. Overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS) and locoregional recurrence-free survival (LRFS) were evaluated. The Cox proportional hazards model was used to analyze the prognostic effect of patient and tumor characteristics on oncological outcomes.

Results

Five year OS, DSS, DFS and LRFS were respectively 53.9%, 72.2%, 68.9% and 67.3%. The p16 status was evaluated in 55 patients with 40% being p16 positive. On univariable analysis, p16 negative SCCUPs had significantly worse survival and recurrence rates in the presence of clinical extranodal extension (cENE) (OS: p=0.0013, DSS: p=0.0099, DFS: p=0.0164, LRFS: p=0.0099) and radiological extranodal extension (rENE) (OS: p=0.0034, DSS: p=0.0137, DFS: p=0.0167, LRFS: p=0.0100). In p16 positive SCCUP patients, rENE had a significantly negative prognostic effect on DFS (p=0.0345) and LRFS (p=0.0367). Total group multivariate analysis identified rENE as an independent negative predictor for all oncological outcomes. The “number of positive lymph nodes” was a second independent predictor for DSS (p=0.0257) and DFS (p=0.0435).

Conclusions

We report favorable oncological outcomes, comparable to previously published results. Although the presence of rENE seems associated with poor oncological outcomes, the differential effect of clinical, radiological and pathological ENE in both p16 positive and negative subgroups remain to be elucidated by further prospective research.

Intraoperative delineation of p16+ oropharyngeal carcinoma of unknown primary origin with fluorescence lifetime imaging: Preliminary report

BACKGROUND

This study evaluated whether fluorescence lifetime imaging (FLIm), coupled with standard diagnostic workups, could enhance primary lesion detection in patients with p16+ head and neck squamous cell carcinoma of the unknown primary (HNSCCUP).

METHODS

FLIm was integrated into transoral robotic surgery to acquire optical data on six HNSCCUP patients' oropharyngeal tissues. An additional 55-patient FLIm dataset, comprising conventional primary tumors, trained a machine learning classifier; the output predicted the presence and location of HNSCCUP for the six patients. Validation was performed using histopathology.

RESULTS

Among the six HNSCCUP patients, p16+ occult primary was surgically identified in three patients, whereas three patients ultimately had no identifiable primary site in the oropharynx. FLIm correctly detected HNSCCUP in all three patients (ROC-AUC: 0.90 ± 0.06), and correctly predicted benign oropharyngeal tissue for the remaining three patients. The mean sensitivity was 95% ± 3.5%, and specificity 89% ± 12.7%.

CONCLUSIONS

FLIm may be a useful diagnostic adjunct for detecting HNSCCUP.

Factors Influencing the Outcome of Head and Neck Cancer of Unknown Primary (HNCUP)

Background: This study on patients with head and neck cancer of unknown primary (HNCUP) assesses the impact of surgical and non-surgical treatment modalities and the tumour biology on the oncological outcome. Methods: A total of 80 patients with HNCUP (UICC I−IV) were treated with simultaneous neck dissection followed by adjuvant therapy, between 1 January 2007 and 31 March 2020. As the primary objective, the influence of treatment modalities on the overall survival (OS), the disease-specific survival (DSS) and the progression-free survival (PFS) were analysed in terms of cox regression and recursive partitioning. The tumour biology served as secondary objectives. Results: The 5-year OS for the entire cohort was 67.7%, (95% CI: 54.2−81.2%), the 5-year DSS was 82.3% (72.1−92.5%) and the 5-year PFS was 72.8% (61.8−83.8%). Cox regression revealed that patients undergoing adjuvant radiotherapy only had a four times higher risk to die compared to patients receiving chemoradiation therapy (HR = 4.45 (1.40; 14.17), p = 0.012). The development of distant metastases had a significantly negative impact on OS (HR = 8.24 (3.21−21.15), p < 0.001) and DSS (HR = 23.79 (6.32−89.56), p < 0.001). Recursive portioning underlined the negative influence of distant metastases on OS (3.2-fold increase in death probability) and DSS (4.3-fold increase in death probability), while an UICC stage of IVb increased the risk for further progression of the disease by a factor of 2. Conclusions: The presence of distant metastases as well as adjuvant treatment with radiation without concomitant chemotherapy, were among others, significant predictors for the overall survival of HNCUP patients, with distant metastases being the most significant predictor.

Transoral robotic surgery for the identification of unknown primary head and neck squamous cell carcinomas: Its effect on the wait and the weight

BACKGROUND

Neck carcinoma of unknown primary (CUP) is a frequent scenario. Transoral robotic mucosectomies (TORM) of pharynx have increased rate of primary identification, but come with cost of treatment delay.

METHODS

We reviewed patients who underwent CUP protocol from 2014 to 2020. Patients with cervical nodes carcinoma and failure to localize a primary source were classified as CUP. We determined primary identification rate and postoperative complications.

RESULTS

We included 65 patients underwent TORM. Surgical approach consisted of lingual and/or palatine tonsillectomies. The primary detection rate was 49.2%. Average weight reduction was 2.5 ± 4.3 kg. The average number of days from consultation to definitive treatment was 52.2 ± 18.3.

CONCLUSION

A systematic approach to patients with CUP showed a promising primary identification rate compared to panendoscopy alone. TORM carries a small risk of complications. The benefits of primary identification must be weighed with the morbidity and delay to definitive treatment.

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.

Relevance of the time interval between surgery and adjuvant radio (chemo) therapy in HPV-negative and advanced head and neck carcinoma of unknown primary (CUP)

INTRODUCTION

In contrast to head and neck squamous cell carcinoma (HNSCC), the effect of treatment duration in HNSCC-CUP has not been thoroughly investigated. Thus, this study aimed to assess the impact of the time interval between surgery and adjuvant therapy on the oncologic outcome, in particular the 5-year overall survival rate (OS), in advanced stage, HPV-negative CUPs at a tertiary referral hospital. 5-year disease specific survival rate (DSS) and progression free survival rate (PFS) are defined as secondary objectives.

MATERIAL AND METHODS

Between January 1st, 2007, and March 31st, 2020 a total of 131 patients with CUP were treated. Out of these, 59 patients with a confirmed negative p16 analysis were referred to a so-called CUP-panendoscopy with simultaneous unilateral neck dissection followed by adjuvant therapy. The cut-off between tumor removal and delivery of adjuvant therapy was set at the median, i.e. patients receiving adjuvant therapy below or above the median time interval.

RESULTS

Depending on the median time interval of 55 days (d) (95% CI 51.42-84.52), 30 patients received adjuvant therapy within 55 d (mean 41.69 d, SD = 9.03) after surgery in contrast to 29 patients at least after 55 d (mean 73.21 d, SD = 19.16). All patients involved in the study were diagnosed in advanced tumor stages UICC III (n = 4; 6.8%), IVA (n = 27; 45.8%) and IVB (n = 28; 47.5%). Every patient was treated with curative neck dissection. Adjuvant chemo (immune) radiation was performed in 55 patients (93.2%), 4 patients (6.8%) underwent adjuvant radiation only. The mean follow-up time was 43.6 months (SD = 36.7 months). The 5-year OS rate for all patients involved was 71% (95% CI 0.55-0.86). For those patients receiving adjuvant therapy within 55 d (77, 95% CI 0.48-1.06) the OS rate was higher, yet not significantly different from those with delayed treatment (64, 95% CI 0.42-0.80; X²₍₁₎ = 1.16, p = 0.281). Regarding all patients, the 5-year DSS rate was 86% (95% CI 0.75-0.96). Patients submitted to adjuvant treatment in less than 55 d the DSS rate was 95% (95% CI 0.89-1.01) compared to patients submitted to adjuvant treatment equal or later than 55 d (76% (95% CI 0.57-0.95; X²₍₁₎ = 2.32, p = 0.128). The 5-year PFS rate of the entire cohort was 72% (95% CI 0.59-0.85). In the group < 55 d the PFS rate was 78% (95% CI 0.63-0.94) and thus not significantly different from 65% (95% CI 0.45-0.85) of the group ≥55 d; (X²₍₁₎ = 0.29, p = 0.589).

CONCLUSIONS

The results presented suggest that the oncologic outcome of patients with advanced, HPV-negative CUP of the head and neck was not significantly affected by a prolonged period between surgery and adjuvant therapy. Nevertheless, oncologic outcome tends to be superior for early adjuvant therapy.

CT texture analysis of tonsil cancer: Discrimination from normal palatine tonsils

The purposes of the study were to determine whether there are differences in texture analysis parameters between tonsil cancers and normal tonsils, and to correlate texture analysis with 18F-FDG PET/CT to investigate the relationship between texture analysis and metabolic parameters. Sixty-four patients with squamous cell carcinoma of the palatine tonsil were included. A ROI was drawn, including all slices, to involve the entire tumor. The contralateral normal tonsil was used for comparison with the tumors. Texture analysis parameters, mean, standard deviation (SD), entropy, mean positive pixels, skewness, and kurtosis were obtained using commercially available software. Parameters were compared between the tumor and the normal palatine tonsils. Comparisons were also performed among early tonsil cancer, advanced tonsil cancer, and normal tonsils. An ROC curve analysis was performed to assess discrimination of tumor from normal tonsils. Correlation between texture analysis and 18F-FDG PET/CT was performed. Compared to normal tonsils, the tumors showed a significantly lower mean, higher SD, higher entropy, lower skewness, and higher kurtosis on most filters (p<0.001). On comparisons among normal tonsils, early cancers, and advanced tonsil cancers, SD and entropy showed significantly higher values on all filters (p<0.001) between early cancers and normal tonsils. The AUC from the ROC analysis was 0.91, obtained from the entropy. A mild correlation was shown between texture parameters and metabolic parameters. The texture analysis parameters, especially entropy, showed significant differences in contrast-enhanced CT results between tumor and normal tonsils, and between early tonsil cancers and normal tonsils. Texture analysis can be useful as an adjunctive tool for the diagnosis of tonsil cancers.

Diagnostic approaches to carcinoma of unknown primary of the head and neck

Squamous cell carcinoma in cervical lymph nodes arising from an undetected primary tumour, termed carcinoma of unknown primary (SCCUP), is a well-recognized clinical presentation within head and neck oncology. SCCUP is a common presentation for patients with human papillomavirus-mediated oropharyngeal cancer (HPV + OPSCC), as patients with HPV + OPSCC often present with smaller primary tumours and early nodal metastasis. Meticulous work-up of the SCCUP patient is central to the management of these patients as identification of the primary site improves overall survival and allows for definitive oncologic resection or more focused radiation when indicated. This review summarizes the comprehensive diagnostic approach to the SCCUP patient, including history and physical examination, methods of biopsy of the cervical lymph node, imaging modalities and intraoperative methods to localize the unknown primary. Novel techniques such as transcervical ultrasound of the oropharynx, narrow band imaging and diagnostic transoral robotic surgery are also discussed.

Influence of postoperative radiotherapy target volumes in unilateral head and neck carcinoma of unknown primary: A multicentric study using propensity score

OBJECTIVE

To compare the impact of two radiation modalities on loco-regional control, survival and tumour emergence, after node dissection for an unilateral head and neck carcinoma of unknown primary (HNCUP).

MATERIALS AND METHODS

This is a multicentric retrospective study of 138 patients with unilateral HNCUP treated between 2002 and 2017. The absence of primary tumour was assessed by a systematic panendoscopy and positron emission tomography. Neck dissection was initially performed for all patients. Radiation Therapy was delivered on ipsilateral lymph node areas in 62 cases (44%: UL-RT group) and on bilateral lymph node areas and the entire pharyngeal mucosa in 77 cases (56%: COMP-RT group). Impact of radiation modalities on locoregional control and overall survival was assessed using propensity score matching method in order to balance baseline characteristics between the two groups.

RESULTS

The population included 80.4% men, 80.4% smokers, 32.6% P16 positive tumours and 71.0% extracapsular extension. After a median follow-up of 5 years, the locoregional control rate was 80.3% in the UL-RT group and 75.3% in the COMP-RT group (p = 0.688). The corresponding rate of contralateral lymph node recurrence was 0% versus 2.6% (p = 0.503) and the rate of tumour emergence was 11.5% versus 9.1% (p = 0.778). No significant difference was observed between the UL-RT and the COMP-RT groups for overall survival (p = 0.9516), specific survival (p = 0.4837) or tumour emergence (p = 0.9034).

CONCLUSION

UL-RT seems to provide similar outcomes as COMP-RT in unilateral HNCUP post-operative management.

TORS elective lingual tonsillectomy has less acute morbidity than therapeutic base of tongue TORS

OBJECTIVE

To determine the impact of diagnostic TORS lingual tonsillectomy (DTLT) on objective swallowing measures for carcinoma of unknown primary (CUP).

METHODS

Between 10/2016-1/2020, 27 patients with p16+ squamous cell carcinoma (SCC) level 2a nodal disease underwent DTLT and ipsilateral neck dissection for CUP. No patient had a history of cutaneous SCC. Patients participated in Modified Barium Swallow (MBS) three weeks post-TORS, which were then compared to those from a contemporaneous cohort of 40 patients with clinically-identified p16+ base of tongue (BOT) primary tumors. DIGEST scores were retrospectively calculated. Univariate and multivariate analysis performed, stratified by BOT glossectomy (n = 40) versus lingual tonsillectomy for CUP (n = 27). Radiation to the resected primary or potential primary sources was omitted if margins were ≥3 mm or if no primary identified.

RESULTS

Twenty-seven consecutive patients with clinical stage cT0N1 HPV-associated OPSCC had a BOT primary pathologically identified in 18/27 (67%). Univariate analysis of functional swallow assessment on MBSImP correlated with improved post-TORS DIGEST scores for CUP. On multivariate analysis (MVA) DIGEST safety scores were improved for CUP than cT1 BOT glossectomy [Odds Ratio (OR) 0.28, p = 0.038]. MVA on matched pT1 CUP (n = 27) vs. pT1 BOT (n = 19), OR of moderate/severe dysphagia for CUP was 0.54 [0.12-2.38, p = 0.417] for DIGEST safety scores and 0.27 [0.06-1.18, p = 0.082] for DIGEST efficiency scores. Moderate/severe dysphagia as determined by DIGEST overall scores for CUP compared to cT1 and pT1 yielded an OR of 0.39 (p = 0.081) and 0.42 (p = 0.195), respectively. Twenty-six total patients received adjuvant RT, and 18 (11 with ≥3 mm margins, 9 with negative specimens) were spared intentional RT to the oropharynx. Median follow-up was 22.6 months with 100% PFS.

CONCLUSIONS

Patients undergoing DTLT for CUP demonstrated acute swallow defecits in the post-operative setting. A comparison of long-term functional results between DTLT and elective irradiation of the primary site should be studied.

LEVEL OF EVIDENCE

Level III.

Metastatic Squamous Cell Carcinoma to the Cervical Lymph Nodes From an Unknown Primary Cancer: Management in the HPV Era

Background

Patients with metastases in the lymph nodes of the neck and no obvious primary tumor, neck cancer with unknown primary (NCUP), represent a management challenge. A majority of patients have metastatic squamous cell carcinoma (SCC), although other histologies do occur.

Methods

We comprehensively reviewed the literature, compared available guidelines, and conferred with an international team of experts.

Results

Positron emission tomography-computed tomography (PET-CT) and fine needle aspiration (FNA) under ultrasound guidance increase accuracy of diagnosis. Immunohistochemistry (IHC), determination of human papilloma virus (HPV) status, by p16 staining or by in situ hybridization (ISH), and next-generation gene sequencing can guide us regarding probable primary sites and tumor biology. Narrow Band Imaging (NBI) has been introduced for the early detection of subtle mucosal lesions. Direct laryngoscopy (DL) and tonsillectomy have long been procedures used in the search for a primary site. More recently, TransOral Robotic Surgery (TORS) or Transoral LASER Microsurgery (TLM) have been introduced for lingual tonsillectomy.

Conclusions

New technologies have been developed which can better detect, diagnose, and treat occult primary tumors. Decisions regarding therapy are based on the primary tumor site (if discovered) and N stage. Options include neck dissection with or without postoperative adjuvant therapy, primary irradiation, or combined chemotherapy with irradiation. The preferred treatment of patients whose primary remains unidentified is controversial.

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.

Swedish National Multicenter Study on Head and Neck Cancer of Unknown Primary: Prognostic Factors and Impact of Treatment on Survival

Introduction  Head and neck cancer of unknown primary (HNCUP) is a rare condition whose prognostic factors that are significant for survival vary between studies. No randomized treatment study has been performed thus far, and the optimal treatment is not established.

Objective  The present study aimed to explore various prognostic factors and compare the two main treatments for HNCUP: neck dissection and (chemo) radiation vs primary (chemo) radiation.

Methods  A national multicenter study was performed with data from the Swedish Head and Neck Cancer Register (SweHNCR) and from the patients' medical records from 2008 to 2012.

Results  Two-hundred and sixty HNCUP patients were included. The tumors were HPV-positive in 80%. The overall 5-year survival rate of patients treated with curative intent was 71%. Age ( p  < 0.001), performance status ( p = 0.036), and N stage ( p = 0.046) were significant factors for overall survival according to the multivariable analysis. Treatment with neck dissection and (chemo) radiation (122 patients) gave an overall 5-year survival of 73%, and treatment with primary (chemo) radiation (87 patients) gave an overall 5-year survival of 71%, with no significant difference in overall or disease-free survival between the 2 groups.

Conclusions  Age, performance status, and N stage were significant prognostic factors. Treatment with neck dissection and (chemo) radiation and primary (chemo) radiation gave similar survival outcomes. A randomized treatment study that includes quality of life is needed to establish the optimal treatment.

Role of Transoral Robotic Surgery in the Work-up of the Unknown Primary

Unknown primary squamous cell carcinoma metastatic to cervical lymph nodes is a relatively rare tumor presentation, although the incidence may be increasing along with the rising incidence of human papilloma virus-mediated oropharyngeal cancers. Traditional diagnostic methods with palatine tonsillectomy and panendoscopy may identify the minority of primary tumors. The addition of a transoral lingual tonsillectomy may improve the diagnostic yield of identifying a primary tumor. Incorporation of transoral robotic surgery may be used for diagnostic purposes to identify a primary site and also for therapeutic purposes, whereby a primary tumor may be completely resected and combined with a neck dissection.

A systematic review on Transoral robotic surgery (TORS) for carcinoma of unknown primary origin: Has tongue base mucosectomy become indispensable?

Background

Transoral robotic surgery (TORS) is increasingly used in head and neck surgery and in carcinoma of unknown primary (CUP) origin specifically. Due to the rising incidence of human papillomavirus (HPV)‐related oropharyngeal squamous cell carcinoma (OPSCC), there is a rationale for finding ways to de‐escalate treatment strategies. This review aims to test the hypothesis that TORS is a meaningful adjunct in the diagnostic (and therapeutic) pathway in CUP in head and neck.

Methods

A structured search of the literature was performed with the search terms ‘TORS’ and ‘Carcinoma of Unknown Primary’.

Results

Two hundred and seventy four cases of CUP in which TORS was used were identified for further analysis. Workup for CUP was comparable in all series with regard to physical examination, fine and/or gross needle examination of cervical nodes, fibre optic endoscopy, imaging and robot assisted mucosectomy of the base of tongue (BOT). Identification rate of the primary tumour was 72% on average (range 17%‐ 90%), and 55%‐ 96% were HPV positive. Clear margins were achieved in 60% (range 0%‐85%) of resected occult tumours. Complication rate of TORS BOT mucosectomy was low with mainly grade I‐III sequelae according to Clavien–Dindo.

Conclusions

Transoral robotic surgery seems to be a useful and safe adjunct in the diagnostic and therapeutic pathway in case of CUP in an era of increasing incidence of HPV‐positive OPSCC.

HPV driven squamous cell head and neck cancer of unknown primary is likely to be HPV driven squamous cell oropharyngeal cancer

OBJECTIVES

To compare risk factors and survival in people with oropharyngeal cancer (OPC) and cancer unknown primary (CUP).

MATERIALS AND METHODS

We recruited 5511 people with head and neck cancer between 2011 and 2014. We collected data on age, gender, smoking, sexual behaviour, treatment intent, stage, co-morbidity, p16 protein overexpression and biological samples. We assessed human papillomavirus (HPV) status using serological response and p16 immunohistochemistry. We followed up participants to identify those who had died. We used Cox proportional hazards regression models to estimate survival and adjust for confounders.

RESULTS

Of the 4843 people with squamous cell cancer 196 had CUP - a prevalence of 4.0% (95% CI 3.5% to 4.6%). Of those people with OPC and CUP 69% (1150/1668) and 60% (106/178) respectively had HPV driven tumours. People with HPV driven tumours were likely to be younger, male, non-smokers, with higher stage disease, a history of oral sex and less co-morbidity. People with HPV negative CUP and HPV driven CUP had the survival of people with a stage II/III HPV negative OPC and a stage I/II HPV driven OPC respectively. The adjusted hazard ratio for HPV driven OPC and CUP compared with HPV negative OPC and CUP was 0.46 (95% CI 0.35 to 0.59) and 0.34 (95% CI 0.14 to 0.82) respectively.

CONCLUSION

HPV driven CUP is likely to be HPV driven OPC. Identifying effective methods of detecting occult OPC could improve CUP management and allow the detection of early lesions in high risk groups.

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.

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.

Intraoperative Primary Tumor Identification and Margin Assessment in Head and Neck Unknown Primary Tumors

OBJECTIVE

Surgical management of the unknown primary head and neck squamous cell carcinoma (UP HNSCC) remains controversial due to challenging clinical diagnosis. This study compares positron emission tomography-computed tomography (PET-CT) findings with intraoperative identification of primary tumors and compares intraoperative frozen-section margins to final histopathology. In addition, adjuvant therapy indications are provided.

STUDY DESIGN

Prospective cohort study.

SETTING

Academic university hospital.

SUBJECTS AND METHODS

Sixty-one patients with UP HNSCC were included. Patients received PET-CT, followed by oropharyngeal transoral laser microsurgery (TLM). Margins were assessed intraoperatively using frozen sections and afterward by final histopathology. Adjuvant treatment was based on final histopathology.

RESULTS

The sensitivity of localizing the primary tumor with PET-CT was 50.9% with a specificity of 82.5%. The primary tumor was found intraoperatively on frozen sections in 82% (n = 50) of patients. Five more tumors were identified on final histopathology, leading to a total of 90% (n = 55). Of the 50 intraoperatively found tumors, 98% (n = 49) had negative margins on frozen sections, and 90% (n = 45) were truly negative on final histopathology. Eighteen patients (29.5%) avoided adjuvant treatment.

CONCLUSION

PET-CT localized the primary tumor in fewer than half the cases. This protocol identified 90% of primary tumors. Intraoperative frozen-section margin assessment has shown potential with a specificity of 92% compared to final histopathology. As a result, adjuvant therapy was avoided in almost one-third of our patients.

DIAGNOSTIC UTILITY OF HUMAN CHORIONIC GONADOTROPIN WASHOUT IN CERVICAL LYMPH NODE FINE-NEEDLE ASPIRATION FOR METASTATIC TESTICULAR CANCER

Objective

This case report will describe the first adjunct use of directly measuring the concentration of human chorionic gonadotropin (HCG) in fine-needle aspiration (FNA) washout for diagnosing metastatic non-semi-nomatous germ cell tumor (NSGCT) of the testicle in a patient with cervical lymphadenopathy.

Methods

We present the clinical, laboratory, imaging, and pathologic findings, along with a review of the literature.

Results

A 23-year-old, otherwise healthy man who first presented with left testicular discomfort and swelling was diagnosed with NSGCT after undergoing a left orchiectomy. A few years later, the patient presented with a 2-cm left supraclavicular mass. Upon ultrasound of the thyroid and soft tissues of the neck, a 1-cm left thyroid nodule was revealed, as well as a 2.8-cm left supraclavicular lymph node, which was cystic in nature and worrisome for metastatic disease given the patient's history of metastatic NSGCT. The results of the FNA of the left thyroid nodule were benign, however the results from the supraclavicular mass were nondiagnostic. Due to the nondiagnostic FNA results, another aspiration with cytopathology and HCG evaluation washout was performed. The HCG aspirate came back with a value of 162 mIU/mL, despite the patient's negative serum HCG results.

Conclusion

This case demonstrates a novel way to diagnose metastatic testicular germ cell tumors utilizing FNA-HCG washout. Future prospective trials are needed to further elucidate this important finding.

Long-term results of elective mucosal irradiation for head and neck cancer of unknown primary in Chinese population: The EMICUP study

Objective

Controversy still exists regarding the volume of radiation for head and neck cancer of unknown primary (HNCUP). Theoretically, elective mucosal irradiation (EMI) should achieve a balance between survival and toxicity. This prospective study was conducted to evaluate the long‐term benefit of EMI in Chinese HNCUP patients.

Methods

A phase II, single‐arm trial was performed at two centers in China. HNCUP patients with pathologically confirmed metastatic squamous cell carcinoma or poorly differentiated carcinoma were enrolled. Patients with metastatic lymph nodes limited to level IV and/or the supraclavicular fossa were excluded. The EMI approach was specifically customized to Chinese patients by differentiating HNCUP as putative nasopharyngeal carcinoma (NPC) or non‐putative NPC. The primary endpoint was 3‐year mucosal recurrence‐free survival (MRFS).

Results

A total of 48 patients were enrolled between 02/02/2010 and 08/01/2018; 46 patients were analyzed, including 24 putative NPC and 22 non‐putative NPC patients. No primary recurrence was observed during a median follow‐up period of 70 months, and only 1 patient experienced out of field recurrence in the contralateral neck. The 3‐year MRFS was 90.6% (95%CI: 76.4%‐96.4%). The 5‐year MRFS, regional‐recurrence free survival (RRFS) and overall survival (OS) were 90.6% (95%CI: 76.4%‐96.4%), 86.0% (95%CI: 71.1%‐93.7%), and 90.6% (95%CI: 76.4%‐96.4%), respectively. No grade 4 acute or late toxicities occurred, and the most frequent grade 3 acute toxicity was oral mucositis (45.7%).

Conclusion

To the best of our knowledge, this is the first prospective study to evaluate the long‐term outcomes of EMI in Chinese HNCUP patients. Excellent MRFS and OS rates were observed. Further randomized studies are warranted.

Finding/identifying primaries with neck disease (FIND) clinical trial protocol: a study integrating transoral robotic surgery, histopathological localisation and tailored deintensification of radiotherapy for unknown primary and small oropharyngeal head and neck squamous cell carcinoma

INTRODUCTION

Carcinomas of unknown primary site (CUP) of the head and neck have historically been worked up and managed heterogeneously. Failure to identify a primary site may result in large radiotherapy mucosal volumes. Transoral approaches such as Transoral Robotic Surgery (TORS) may improve the yield of identifying hidden primaries. We aim to assess the oncological and functional outcomes of a combined treatment approach with TORS and tailored radiotherapy.

METHODS AND ANALYSIS

Twenty-five patients with metastatic squamous cell carcinoma to the neck without clinical or radiographic evidence of a primary site will be enrolled in a phase II trial. Patients will undergo a diagnostic or therapeutic approach with TORS based on specific algorithms incorporating tailored radiotherapy according to the location and laterality of the primary tumour. The primary outcome is to evaluate the out-of-field failure rate over a 2-year period. Secondary outcomes include identification rates, survival outcomes, patient reported outcomes and functional swallowing outcomes.

ETHICS AND DISSEMINATION

The University Health Network Research Ethics Board approved this study (ID 15-9767). The results will be published in an open access journal.

TRIAL REGISTRATION NUMBER

NCT03281499.

A Review of Controversial Issues in the Management of Head and Neck Cancer: A Swiss Multidisciplinary and Multi-Institutional Patterns of Care Study-Part 2 (Radiation Oncology)

Background: The Head and Neck Cancer Working Group of Swiss Group for Clinical Cancer Research (SAKK) has investigated the level of consensus (LOC) and discrepancy in everyday practice of diagnosis and treatment in head and neck cancer.

Materials and Methods: An online survey was iteratively generated with 10 Swiss university and teaching hospitals. LOC below 50% was defined as no agreement, while higher LOC were arbitrarily categorized as low (51–74%), moderate (75–84%), and high (≥85%).

Results: Any LOC was achieved in 62% of topics (n = 60). High, moderate, and low LOC were found in 18, 20, and 23%, respectively. Regarding Head and Neck Surgery, Radiation Oncology, Medical Oncology, and biomarkers, LOC was achieved in 50, 57, 83, and 43%, respectively.

Conclusions: Consensus on clinical topics is rather low for surgeons and radiation oncologists. The questions discussed might highlight discrepancies, stimulate standardization of practice, and prioritize topics for future clinical research.

A Review of Controversial Issues in the Management of Head and Neck Cancer: A Swiss Multidisciplinary and Multi-Institutional Patterns of Care Study-Part 1 (Head and Neck Surgery)

Background: The Head and Neck Cancer Working Group of Swiss Group for Clinical Cancer Research (SAKK) has investigated the level of consensus (LOC) and discrepancy in everyday practice of diagnosis and treatment in head and neck cancer. Materials and Methods: An online survey was iteratively generated with 10 Swiss university and teaching hospitals. LOC below 50% was defined as no agreement, while higher LOC were arbitrarily categorized as low (51-74%), moderate (75-84%), and high (≥85%). Results: Any LOC was achieved in 62% of topics (n = 60). High, moderate and low LOC were found in 18, 20, and 23%, respectively. Regarding Head and Neck Surgery, Radiation Oncology, Medical Oncology, and biomarkers, LOC was achieved in 50, 57, 83, and 43%, respectively. Conclusions: Consensus on clinical topics is rather low for surgeons and radiation oncologists. The questions discussed might highlight discrepancies, stimulate standardization of practice, and prioritize topics for future clinical research.

Heterogeneity in the clinical presentation, diagnosis, and treatment initiation of p16-positive oropharyngeal cancer

BACKGROUND

Human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) has a patient demographic, presentation, and clinical treatment response distinct from HPV-unassociated OPSCC. The heterogeneity in presentation and diagnosis within a patient population with HPV-positive OPSCC and its impact on times to presentation, diagnosis, and treatment have yet to be characterized.

PARTICIPANTS

Patients with biopsy-proven p16-positive OPSCC seen and/or treated at our institution between 2008 and 2018. Of 136 patients with OPSCC seen and/or treated at our institution, 101 met criteria for inclusion.

METHODS

Patients were grouped by several parameters including presenting symptom category (asymptomatic neck mass, neck mass with primary-site symptoms, or primary-site symptoms without a neck mass), p16 status on fine-needle aspiration (FNA), and date of presentation. Median time intervals between presentation to imaging, biopsy, and treatment were compared within each parameter using the Kruskal-Wallis test with a significance level of 0.05.

RESULTS

Sixty-five of the 101 study patients presented with a neck mass. Patients without a neck mass had a longer interval from presentation to imaging than patients with a neck mass (median 4 vs 0 days, p = 0.025). Initial FNA obtained on 61 patients was positive for p16 in 19 patients. Unknown or negative p16 status on FNA was associated with shorter intervals from initial imaging to treatment initiation (39 vs 46.5 days, p = 0.045). Patients presenting in the final three years had a longer interval from presentation to treatment initiation (55 vs 41 days, p = 0.024).

CONCLUSION

A neck mass is absent from the clinical picture of a substantial proportion of HPV-associated OPSCC patients. Primary-site symptom category and regional metastasis were not associated with differences in times to diagnosis or treatment initiation at this major referral center. The increased awareness and complexity of treatment decisions related to OPSCC may contribute to the delays in treatment initiation observed in patients with p16-positive FNAs and those who presented in more recent years.

Absence of disruptive TP53 mutations in high-risk human papillomavirus-driven neck squamous cell carcinoma of unknown primary

BACKGROUND

To enforce the evidence for causality between high-risk human papillomavirus (hrHPV) infections and neck squamous cell carcinoma from unknown primary (NSCCUP) and provide biological basis for treatment de-intensification, we searched for TP53 mutations in association with HPV status.

METHODS

TP53 mutations were searched for by amplification of exons 4 to 10.

RESULTS

Of the 70 NSCCUP, 27 (39%) harbored HPV infection. TP53 sequencing resulted in the identification of 19 patients harboring single mutations including 16 disruptive alterations (84%). The association of TP53 mutations and HPV could be evaluated in 48 NSCCUP including those with disruptive mutation in any exon (n = 16) and those without mutations but with complete sequence of exons 4 to 9 (n = 32): no disruptive mutations were found in the 17 HPV-driven NSCCUP but in 16 of the 31 non-HPV-driven NSCCUP (P = .0002).

CONCLUSION

In a fraction of cases, NSCCUP is an HPV-driven entity harboring wild-type TP53 gene or nondisruptive TP53 mutations. HPV-driven NSCCUP might benefit from treatment de-intensification.

Does Cancer of Unknown Primary (CUP) Truly Exist as a Distinct Cancer Entity?

Cancer of unknown primary (CUP) designates an enigmatic cancer entity with histologic confirmation of malignancy from a metastasis but no identifiable primary tumor in spite of a thorough diagnostic work-up. In this review, we discuss the validity of CUP as a distinct cancer entity as well as diagnostic pitfalls. As arguments against a distinct entity, the diagnosis of CUP is erroneous in some cases. Diagnostic pitfalls include incomplete diagnostics, uncertainty in classifying a lesion as either primary or metastasis and mistaking a relapse of an antecedent malignancy as CUP due to histologic and immunohistologic disparities. Given the high frequency of prior malignancies in CUP patients, relapse of an antecedent cancer should always be carefully excluded. Gene expression profiling-based classifier assays aim at aligning the molecular profile of CUP patients with established primary cancer patterns for highest congruency in order to identify the putative primary and treat accordingly. However, the spectrum of predicted putative primaries by molecular techniques is somewhat at odds with the primaries identified in autopsy series. Also, a first randomized clinical trial did not show superiority of primary-tailored therapy over unspecific platinum-based chemotherapy. CUP cases share an aggressive clinical course, atypical metastasis pattern, rapid progression of metastases, a generally poor response to chemotherapy and dismal outcome as distinct clinical features. Metastatic spread appears to take place in the early stages of tumor evolution, with CUP metastases subsequently undergoing genetic evolution toward a chromosomally highly complex and instable karyotype independent from the primary tumor. In clinical practice, the diagnosis of CUP is valid when no primary tumor is detectable. Treatment should ideally offer broad spectrum coverage across numerous malignancies and be well-established in CUP as is the case for carboplatin/paclitaxel and cisplatin / gemcitabine in particular, but it should also cover the most likely putative primary. The diligent diagnosis of CUP is warranted for clinical trials, making the eligibility process particularly laborious. In conclusion, we deem CUP a distinct cancer entity and the diagnosis accurate in most patient cases.

Head and neck carcinoma of unknown primary

In adult cervicofacial pathology, carcinoma of unknown primary is defined as lymph-node metastasis the anatomic origin of which is not known at the time of initial management. It constitutes up to 5% of head and neck cancers. Presentation may suggest benign pathology, delaying and confusing oncologic treatment. Diagnostic strategy in cervical lymph node with suspicion of neoplasia requires exhaustive work-up to diagnose malignancy and, in 45% to 80% of cases, depending on the series, to identify the primary site. Histologic types comprise squamous cell carcinoma, thyroid carcinoma, adenocarcinoma, neuroendocrine carcinoma and undifferentiated carcinoma. Association is sometimes found with human papilloma virus or Epstein Barr virus, guiding treatment. The objective of the present study was to provide clinicians with the necessary diagnostic tools, based on the current state of clinical, imaging and pathologic knowledge, and to detail treatment options.

Sustained complete response to erlotinib in squamous cell carcinoma of the head and neck: A case report

BACKGROUND

Squamous cell carcinoma of head and neck (SCCHN) is the fifth most common cancer worldwide. Inhibition of epidermal growth factor receptor signaling has been shown to be a critical component of therapeutic option. Herein, we report a case of durable complete response to erlotinib.

CASE SUMMARY

An 81-year-old Caucasian male who presented with metastatic poorly differentiated squamous cell carcinoma of right cervical lymph nodes (levels 2 and 3). Imaging studies including (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (CT) and contrast-enhanced CT scan of neck and chest did not reveal any other disease elsewhere. Panendoscopic examination with random biopsy did not reveal malignant lesion in nasopharynx, oropharynx, and larynx. He underwent modified neck dissection and postoperative radiation. Within 2 mo after completion of radiation, he developed local recurrence at right neck, which was surgically removed. Two mo after the salvage surgery, he developed a second recurrence at right neck. Due to suboptimal performance status and his preference, he started erlotinib treatment. He achieved partial response after first 2 mo of erlotinib treatment, then complete response after total 6 mo of erlotinib treatment. He developed sever skin rash and diarrhea including Clostridium difficile infection during the course of erlotinib treatment requiring dose reduction and eventual discontinuation. He remained in complete remission for more than two years after discontinuation of erlotinib.

CONCLUSION

We report a case of metastatic SCCHN achieving durable complete response from erlotinib. Patient experienced skin rash and diarrhea toxicities which were likely predictors of his treatment response.

Transoral tongue base mucosectomy for the identification of the primary site in the work-up of cancers of unknown origin: Systematic review and meta-analysis

BACKGROUND

The use of transoral robotic surgery (TORS) and laser microsurgery (TLM) in the diagnosis and identification of the site of the unknown primary has become increasingly common. This systematic review and meta-analysis aims to assess the use and efficacy of TORS and TLM for this indication.

METHOD

Systematic review and meta-analysis of studies employing TORS or TLM in diagnosis of the unknown primary tumor site in patients with cervical nodal metastases of squamous cell origin. MEDLINE, EMBASE and CINHAL were searched from inception to July 2018 for all studies that used TORS and or TLM in identifying the unknown primary.

RESULTS

251 studies were identified, of which 21 were eligible for inclusion. The primary tumour was identified by TORS/TLM in 78% of patients (433 out of 556). Tongue base mucosectomy (TBM) identified the primary in 222 of 427 cases (53%). In patients with negative physical examination, diagnostic imaging and PETCT, TBM identified the primary in 64% (95% CI 50, 79) cases. In patients who had negative CT/MRI imaging, negative PETCT and negative EUA and tonsillectomy, TBM identified a tongue base primary in 78% (95% CI 41, 92) cases. Haemorrhage, the commonest complication, was reported in 4.9% cases. Mean length of stay varied between 1.4 and 6.3 days.

CONCLUSION

Tongue base mucosectomy, performed by TORS or TLM, is highly efficacious in identifying the unknown primary in the head and neck region.

Human papillomavirus and p16 immunostaining, prevalence and prognosis of squamous carcinoma of unknown primary in the head and neck region

The prevalence of human papillomavirus (HPV) in squamous cell carcinoma of unknown primary in the head and neck (SCCUPHN), and prognosis by HPV status of SCCUPHN patients has been difficult to estimate because of the rarity of this subtype. In MEDLINE, Epub Ahead of Print, In-Process & Other Non-Indexed Citations, EMBASE, Cochrane library and Web of Science searches, observational studies and clinical trials that reported survival rates of patients with SCCUPHN by HPV status were identified. Meta-analysis estimated the prevalence and prognosis (overall survival, OS; progression-free survival, PFS) of SCCUPHN by HPV status, and compared them to studies of oropharyngeal squamous cell carcinoma (OPSCC) from the same institutions and across continents. In 17 SCCUPHN studies (n = 1,149) and 17 institution-matched OPSCC studies (n = 6,522), the pooled HPV prevalence of SCCUPHN was 49%, which was only 10% (95%CI: 1-19%) lower than OPSCC prevalence in the underlying population. Estimated 5-year OS for HPV-negative SCCUPHN was 44% (95%CI: 36-51%) vs. HPV-positive SCCUPHN of 91% (95%CI: 86-96%); hazard ratio (HR) for OS was 3.25 (95%CI: 2.45-4.31) and PFS was 4.49 (95%CI: 2.88-7.02). HRs by HPV status for OPSCC were similar to that in SCCUPHN. While North American SCCUPHNs had higher HPV prevalence than European SCCUPHNs (OR = 2.68 (95%CI: 1.3-5.6)), HR of OS for HPV-negative vs. HPV-positive patients were similar in both continents (HRs of 3.78-4.09). Prevalence of HPV among SCCUPHN patients were lower than in OPSCC. The survival benefit conferred by being HPV-positive was similar in SCCUPHN as in OPSCCs, independent of continent.