p16 expression in carcinoma of unknown primary: diagnostic indicator and prognostic marker

Indications for oropharyngeal biopsy in head and neck squamous cell carcinoma of unknown primary: A systematic review (HNSCCUP)

INTRODUCTION

Patients presenting with head and neck squamous cell carcinoma of unknown primary (HNSCCUP) remain challenging clinical scenarios as large variation exists in practices used to locate the primary.

OBJECTIVE

The objective of this systematic review is to review of the literature and offer recommendations for oropharyngeal biopsies in HNSCCUP.

METHOD

Pubmed, Medline and Embase were searched to identify studies from inception to October 2021. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed.

RESULTS

A total of 483 articles were included and screened, 41 studies met the inclusion criteria, including over 3400 patients from the original articles (122 of these patients were reported on in two sequential articles by a single author - table 1) and 4 large metaanalyses including 1852 patients. The primary site identification rate following random biopsies or deep tissue biopsies is less than 5% in most studies. The mean detection rate following ipsilateral tonsillectomy is 34%; two pooled analyses indicate that the mean detection rate following tongue base mucosectomy is 64%, with this figure rising when the tonsils are negative.

CONCLUSIONS

High level evidence is lacking, with heterogeneity in the reported studies. Published meta-analyses are based on retrospective data. There is little evidence supporting the practice of random/non-directed oropharyngeal biopsies. Available evidence supports palatine tonsillectomy and tongue base mucosectomy compared to deep tissue biopsies.

Feasibility of Using Needle Rinse Fluid for Cobas Human Papillomavirus (HPV) Assay in Diagnosing HPV+ Oropharyngeal Cancer with Neck Lymph Node Aspiration

BACKGROUND

Human papillomavirus (HPV) is a crucial prognostic factor in oropharyngeal cancer (OPC). p16 is a surrogate marker for diagnosing HPV+ OPC, however it is not direct evidence of HPV existence.

OBJECTIVE

The purpose of our study was to evaluate an HPV DNA test-Cobas HPV assay-in diagnosing HPV+ OPC through neck lymph node aspiration.

METHODS

Patients with suspected neck mass who received fine needle aspiration (FNA) or core needle biopsy (CNB) at the National Taiwan University Hospital between January 2018 and December 2022 were reviewed. Besides routine cytology and pathology study, needle rinse fluid was collected for the Cobas HPV assay to detect high-risk HPV.

RESULTS

We analyzed 137 patients with suspected lymph nodes, 32 (23.4%) of whom were HPV+ OPC patients and 105 (76.6%) of whom had non-HPV-related disease. FNA was performed in 31 patients and CNB was performed in 106 patients, according to the size and necrosis status of the lymph nodes. For diagnosing HPV+ OPC, CNB combined with p16 immunohistochemistry staining showed sensitivity of 93.3%, specificity of 97.8%, positive predictive value (PPV) of 87.5%, negative predictive value (NPV) of 98.9%, and accuracy of 97.2%. On the other hand, for the needle rinse Roche Cobas HPV assay, the test showed sensitivity of 96.9%, specificity of 100%, PPV of 100%, NPV of 99.1%, and accuracy of 99.3%. Compared with p16 IHC staining, the Cobas HPV test showed better PPV with statistical significance (p = 0.04).

CONCLUSION

The Cobas HPV assay is a US FDA-approved, highly automated, and readily used technique to directly detect the presence of high-risk HPV. We recommend utilizing the Cobas HPV assay in combination with routine cytology or histopathology examination in the work-up of neck lymphadenopathy.

Radiotherapy to the neck after neck dissection for head and neck squamous cell carcinoma from an unknown primary: A narrative review

PURPOSE

To conduct a comprehensive narrative review of the evidence for radiotherapy target volumes to the neck, after neck dissection, for head and neck squamous cell carcinoma from an unknown primary (HNSCCUP). Inclusion or exclusion of mucosal irradiation is not the focus of interest for this review article.

MATERIALS AND METHODS

Literature (PubMed-Medline, EMBASE database and Cochrane library) was searched using the relevant keywords. The search results were limited to the studies published in year 2000 or after.

RESULTS

Eight studies met the inclusion criteria. All studies were retrospective in nature. The incidence of contralateral recurrence rates in the untreated neck when the involved neck only is treated remains very low (0%-10%). Survival has improved over the past two decades, most likely due to improved diagnostic techniques and the increase in incidence of HPV-related disease.

CONCLUSION

Given the rarity of disease, level one evidence from randomised controlled trials is lacking. Available data are retrospective but support unilateral post-operative radiotherapy as a treatment option in selected cases.

A Systematic Review of Diagnostic and Prognostic Biomarkers for Head and Neck Cancer of Unknown Primary: An Unmet Clinical Need

Head and neck cancer of unknown primary (HNCUP) is defined as cervical lymph node metastases without a detectable primary tumor. The management of these patients presents a challenge to clinicians since guidelines in the diagnosis and treatment of HNCUP remain controversial. An accurate diagnostic workup is fundamental for the search for the hidden primary tumor to allow the best adequate treatment strategy. The purpose of this systematic review is to present the currently available data about the diagnostic and prognostic molecular biomarkers for HNCUP. Systematic research in an electronic database was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol and identified 704 articles, of which 23 studies were selected and included in the analysis. Fourteen studies investigated HNCUP diagnostic biomarkers and focused on the human papilloma virus (HPV) and the Epstein-Barr virus (EBV) due to the strong associations with oropharyngeal cancer and nasopharyngeal cancer, respectively. HPV status was shown to possess prognostic value, correlating with longer disease-free survival and overall survival. HPV and EBV are the only available HNCUP biomarkers, and they are already used in clinical practice. A better characterization of the molecular profiling and the development of tissue-of-origin classifiers are necessary to improve the diagnosis, staging, and therapeutic management of patients with HNCUP.

Predictive Value of HPV, p53, and p16 in the Post-Treatment Evolution of Malignant Tumors of the Oropharynx and Retromolar Trigone-Oropharynx Junction

Background and objectives: Knowledge of the interactions and influences of infectious, genetic, and environmental factors on the evolution and treatment response of malignant tumors is essential for improving the management of the disease and increasing patient survival. The objective of this study was to establish the contribution of human papillomavirus (HPV), as well as p53 and p16 tumor markers, alongside associated factors (smoking and alcohol consumption), in the progression of malignancies located in the oropharynx and at the retromolar trigone–oropharyngeal junction. Materials and Methods: We performed a prospective study including 50 patients with malignant tumors of the oropharynx and retromolar trigone–oropharyngeal junction. In all patients, the presence and type of HPV were determined, as well as the status of the tumor markers p53 and p16. The associated risk factors, biopsy results, treatment method, and post-treatment evolution were all documented. Statistical analyses were performed to evaluate the correlations between the determining factors and their influence on the post-treatment evolution. An overall increased survival rate was found in HPV(+) patients. Results: Our study outlined the prevalence of different high-risk subtypes of HPV from the ones presented by other studies, suggesting a possible geographic variation. Correlations between the p53 and p16 statuses and patient survival could be established. The association of smoking and alcohol consumption strongly correlated with an unfavorable evolution. Conclusions: Awareness of the differences in the post-treatment evolution of the patients in relation to the presence of the factors determined in our study could change the future management of such cases for ensuring improved treatment outcomes.

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.

CUP Syndrome-Metastatic Malignancy with Unknown Primary Tumor

BACKGROUND

2-4% of newly diagnosed cases of malignant disease involve cancer of unknown primary (CUP). This mixed entity is one of the 6 most common types of malignant disease in Germany. Highly refined treatment strategies can now be offered to patients with CUP.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed with an emphasis on articles from the past decade. The current guidelines and recommendations of specialty societies were also considered in the evaluation.

RESULTS

CUP most commonly manifests itself as metastases to the lymph nodes, lungs, liver, or bones. With the aid of imaging studies, including functional hybrid imaging and further medical examination, a primary tumor can be discovered in up to 40% of patients initially diagnosed with CUP. Immunohistochemistry guided by histomorphology often enables precise characterization of the lesion and can be supplemented, in selected cases, by molecular-genetic diagnostic evaluation. The most commonly detected types of primary tumor are cancers of the lung, pancreas, liver, and biliary system. For patients with local metastases, surgical resection or radiotherapy with curative intent is usually indicated, sometimes in the framework of a multimodal treatment concept. The median 2-year survival of patients with disseminated CUP is only 20%. For such patients, specific types of systemic therapy are recommended on the basis of the diagnostic characterization of the disease. Immune-modulatory antibodies can be effective, particularly in the treatment of CUP that has been characterized with biomarkers, but should still be considered experimental at present.

CONCLUSION

A combination of conventional and innovative diagnostic methods enables the provision of highly refined therapeutic strategies to patients with CUP who are undergoing treatment in interdisciplinary cancer centers.

Human Papillomavirus Testing in Head and Neck Carcinomas: Guideline From the College of American Pathologists

Context Human papillomavirus (HPV) is a major cause of oropharyngeal squamous cell carcinomas, and HPV (and/or surrogate marker p16) status has emerged as a prognostic marker that significantly impacts clinical management. There is no current consensus on when to test oropharyngeal squamous cell carcinomas for HPV/p16 or on which tests to choose. Objective To develop evidence-based recommendations for the testing, application, interpretation, and reporting of HPV and surrogate marker tests in head and neck carcinomas. Design The College of American Pathologists convened a panel of experts in head and neck and molecular pathology, as well as surgical, medical, and radiation oncology, to develop recommendations. A systematic review of the literature was conducted to address 6 key questions. Final recommendations were derived from strength of evidence, open comment period feedback, and expert panel consensus. Results The major recommendations include (1) testing newly diagnosed oropharyngeal squamous cell carcinoma patients for high-risk HPV, either from the primary tumor or from cervical nodal metastases, using p16 immunohistochemistry with a 70% nuclear and cytoplasmic staining cutoff, and (2) not routinely testing nonsquamous oropharyngeal carcinomas or nonoropharyngeal carcinomas for HPV. Pathologists are to report tumors as HPV positive or p16 positive. Guidelines are provided for testing cytologic samples and handling of locoregional and distant recurrence specimens. Conclusions Based on the systematic review and on expert panel consensus, high-risk HPV testing is recommended for all new oropharyngeal squamous cell carcinoma patients, but not routinely recommended for other head and neck carcinomas.

[HPV - A different view on Head and Neck Cancer]

Head and neck cancer is the sixth most common cancer with over 500000 annually reported incident cases worldwide. Besides major risk factors tobacco and alcohol, oropharyngeal squamous cell carcinomas (OSCC) show increased association with human papillomavirus (HPV). HPV-associated and HPV-negative OSCC are 2 different entities regarding biological characteristics, therapeutic response, and patient prognosis. In HPV OSCC, viral oncoprotein activity, as well as genetic (mutations and chromosomal aberrations) and epigenetic alterations plays a key role during carcinogenesis. Based on improved treatment response, the introduction of therapy de-intensification and targeted therapy is discussed for patients with HPV OSCC. A promising targeted therapy concept is immunotherapy. The use of checkpoint inhibitors (e.g. anti-PD1) is currently investigated. By means of liquid biopsies, biomarkers such as viral DNA or tumor mutations in the will soon be available for disease monitoring, as well as detection of treatment failure. By now, primary prophylaxis of HPV OSCC can be achieved by vaccination of girls and boys.

Detection of Merkel Cell Polyomavirus in Seborrheic Keratosis

Seborrheic keratosis (SK) is the most common benign cutaneous neoplasm. A subset shows increased p16 expression. Since SK shares several features with verruca vulgaris, e.g., increased p16 expression, human papillomaviruses (HPV) have been suggested as possible causal agents. However, a relevant association could not be established between HPV and SK. In the present study we aimed to investigate the presence of Merkel cell polyomavirus (MCPyV) in relation to p16 expression in SK. P16 expression was investigated using immunohistochemistry (IHC). Presence of MCPyV was assessed in 23 formalin-fixed paraffin-embedded tissue samples of SK by molecular techniques (i.e., PCR and FISH) and IHC. 16/23 SK showed strong to moderate p16 expression. 6/23 of SK were MCPyV positive by PCR which was confirmed by FISH. Of interest, two samples with strong FISH signals also showed MCPyV expression as tested by IHC. Samples with weaker signal intensity were negative in IHC. P16 expression was not associated with the presence of MCPyV. Concluding, the detection of MCPyV DNA by PCR and FISH in SK reflects the widespread prevalence of MCPyV in the skin. However, low detection rates exclude MCPyV as a major pathogenic factor in SK, most likely representing a coincidental infection. P16 IHC does not appear as useful adjunctive surrogate marker for the presence of MCPyV in SK.

[Advances in the management of cervical lymphadenopathies of unknown primary: advances in diagnostic imaging and surgical modalities and new international staging system]

INTRODUCTION

Cervical lymphadenopathies of unknown primary represent 3 % of head and neck cancers. Their diagnostic work up has largely changed in recent years. This review provides an update on diagnostic developments and their potential therapeutic impact.

MATERIALS AND METHODS

This is a systematic review of the literature.

RESULTS

In recent years, changes in epidemiology-based prognostic factors such as human papilloma virus (HPV) cancers, advances in imaging and minimally invasive surgery have been integrated in the management of cervical lymphadenopathies of unknown primary. In particular, systematic use of PET scanner and increasing practice of robotic or laser surgery have contributed to increasing detection rate of primary cancers. These allow more adapted and personalized treatments. The impact of changes in the eighth TNM staging system is discussed.

CONCLUSION

The management of cervical lymphadenopathies of unknown primary cancer has changed significantly in the last 10 years. On the other hand, practice changes will have to be assessed.

Neck dissection for unknown cancer of the head and neck in the era of chemoradiation

PURPOSE

To report outcomes for patients with cervical lymph node metastases from an unknown primary site of the head and neck treated with either non-operative therapy or neck dissection followed by adjuvant therapy.

MATERIALS AND METHODS

All patients with squamous cell carcinoma of an unknown primary site of the head or neck seen between 2003 and 2013 were reviewed. The Kaplan-Meier method was used to estimate overall survival, local recurrence free survival, loco-regional recurrence free survival, and progression free survival. The log-rank test and proportional hazards regression were used to analyze factors influencing outcomes.

RESULTS

Of 2258 patients with a new diagnosis of head and neck cancer, no primary site was identified in 66 patients. Twenty-nine patients were treated with definitive non-operative therapy (15 with chemoradiation and 14 with radiation alone). Thirty-seven patients received an upfront neck dissection followed by adjuvant radiation or chemoradiation. Three-year loco-regional recurrence free survival, progression free survival, and overall survival were 55.9%, 55.4%, and 69.4% respectively. Patients treated with preoperative neck dissection had improved local recurrence free survival (96.7% vs 54.1%, p=0.003) and loco-regional recurrence free survival (82.2% vs 46.4%, p=0.068) compared to patients treated with definitive chemoradiation with no difference in overall survival (p=0.641).

CONCLUSIONS

Neck dissection improved local and regional control but not overall survival in patients with unknown primary squamous cell carcinoma of the head and neck over non-operative therapy alone.

The role of high-risk human papillomavirus infections in laryngeal squamous cell carcinoma

The contribution of human papillomavirus (HPV) to the development and clinical outcome of oropharyngeal cancers has been well documented. The association of HPV in laryngeal squamous cell carcinoma (LSCC) has been examined in several studies, but controversy exists regarding its role in carcinogenesis, the outcome of the patients and thus, clinical significance of HPV testing in LSCC. In this review, we give an update of known associations between HPV-positive testing and carcinogenesis in laryngeal cancer. In an early study, the HPV-DNA detection rate in LSCC was documented being 24.0% with significant regional differences. Non-HPV-16 types were more often detected in LSCC when compared to the oropharynx. Later, single institution case series revealed markedly fewer amounts (<10%) of HPV DNA in LSCC and the results suggested that high-risk HPV infections seem to be biologically irrelevant in most LSCC. The significance of p16INK4a (p16) expression as a surrogate marker towards high-risk HPV infection and the outcome in LSCC is doubtful, since only few p16-positive LSCC samples are HPV RNA positive and accordingly there was poor correlation of p16-test results towards the outcome in LSCC. Recent meta-analysis (n = 2739) and large case series (n = 1042) of LSCC revealed the true rate of HPV-driven LSCC being 8.6%, respectively, <5%. In the latter the rate of DNA-, DNA/RNA-, DNA/p16, and DNA/RNA/p16 positivity was 5.7, 3.1, 1.9, and 1.5%, respectively. These results indicate relevant amounts of insignificant/transient HPV infection in LSCC specimen. However, in the same study the rate of transforming HPV infections increased since 2000, and younger patients had higher amounts of HPV-driven LSCC. Serologic testing of E6/E7 antibodies additionally revealed odds ratios between 2 and 5 as a hint for a weak contribution of high-risk HPV infection and the development of LSCC. The contribution of HPV for the development of LSCC needs future investigations, to date, routine HPV testing of LSCC specimen is not warranted.

Prognostic factors for head and neck cancer of unknown primary including the impact of human papilloma virus infection

Background

Head and neck cancer of unknown primary (HNCUP) is rare and prospective studies are lacking. The impact of different prognostic factors such as age and N stage is not completely known, the optimal treatment is not yet established, and the reported survival rates vary. In the last decade, human papilloma virus (HPV) has been identified as a common cause of and important prognostic factor in oropharyngeal cancer, and there is now growing interest in the importance of HPV for HNCUP. The aim of the present study on curatively treated HNCUP was to investigate the prognostic importance of different factors, including HPV status, treatment, and overall survival.

Methods

A search for HNCUP was performed in the Swedish Cancer Registry, Western health district, between the years 1992–2009. The medical records were reviewed, and only patients with squamous cell carcinoma or undifferentiated carcinoma treated with curative intent were included. The tumor specimens were retrospectively analyzed for HPV with p16 immunostaining.

Results

Sixty-eight patients were included. The mean age was 59 years. The majority were males, and had N2 tumors. Sixty-nine percent of the tumors were HPV positive using p16 staining. Patients who were older than 70 years, patients with N3-stage tumors, and patients with tumors that were p16 negative had a significantly worse prognosis. The overall 5-year survival rate for patients with p16-positive tumors was 88% vs 61% for p16-negative tumors. Treatment with neck dissection and postoperative radiation or (chemo) radiation had 81 and 88% 5-year survival rates, respectively. The overall and disease-free 5-year survival rates for all patients in the study were 82 and 74%.

Conclusions

Curatively treated HNCUP had good survival. HPV infection was common. Independent prognostic factors for survival were age over 70 years, HPV status and N3 stage. We recommend that HPV analysis should be performed routinely for HNCUP. Treatment with neck dissection and postoperative radiation or (chemo) radiation showed similar survival rates.

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

Background and Purpose

This review aims to provide a comprehensive overview of the literature and elucidate open questions for future clinical trials concerning diagnostics and treatment modalities for cervical cancer of unknown primary (CUP).

Methods

A literature search for head and neck CUP was performed with focus on diagnostics and therapies as well as molecular markers.

Results

High level evidence on CUP is limited. However, it seems that a consensus exists regarding the optimal diagnostic procedures. The correct implementation of biomarkers for patient stratification and treatment remains unclear. An even greater dispute dominates about the ideal treatment with publications ranging from sole surgery to surgery with postoperative bilateral radiotherapy with inclusion of the mucosa and concomitant chemotherapy.

Conclusions

Cervical CUP represents a very heterogeneous malignant disease. On this account many aspects concerning treatment optimization remain unclear, despite a considerable number of publications in the past. Future research in form of prospective randomized trials is needed in order to better define patient stratification criteria and enable tailored treatment.

[HPV-associated head and neck cancer : mutational signature and genomic aberrations]

A significantly increasing proportion of oropharyngeal head and neck carcinomas (OSCC) in North America and Europe are associated with human papillomavirus (HPV) infections. HPV-related OSCC is regarded as a distinct tumor type with regard to its cellular, biologic, and clinical characteristics. Patients with HPV-related OSCC have significantly better local control, but higher rates of regional lymph node and distant metastases as compared to patients with HPV-negative OSCC. Classical molecular genetic investigations demonstrated specific chromosomal aberration signatures in HPV-related OSCC, and recent developments in next generation sequencing (NGS) technology have rendered possible the sequencing of entire genomes, and thus detection of specific mutations, in just a few days. Initial data from The Cancer Genome Atlas (TCGA) project obtained by using genome-wide high throughput methods have confirmed that HPV-related OSCC contain fewer, albeit more specific mutations than HPV-negative tumors. Additionally, these data revealed the presence of specific-potentially therapeutically targetable-activating driver mutations in subgroups of HPV-positive OSCC, some of which have a prognostic impact. Specific targeted NGS technologies provide new possibilities for identification of diagnostic, prognostic, and predictive biomarkers and the development of personalized cancer treatment. Patients with HPV-positive tumors are likely to profit from these developments in the future, since the genetic alterations are relatively homogenous and frequently lead to signal pathway activation. There is an urgent need for network research activities to carry out the necessary basic research in prospective cohort studies.

The prevalence of human papillomavirus in squamous cell carcinoma of unknown primary site metastatic to neck lymph nodes: a systematic review

A subset of head and neck squamous cell carcinoma, which mainly arise from the crypt epithelium of the palatine and lingual tonsils, may be caused by high-risk human papillomavirus (HPV) infections. This topographical restriction together with other overlapping clinical features have led investigators to suspect that HPV plays a role in squamous cell carcinoma of unknown primary (SCCUP) site metastatic to neck lymph nodes. We performed a systematic review of articles listed in PubMed to identify studies testing HPV and/or p16(INK4a) status (p16) in tissue samples from initial and definitive SCCUP. The prevalence of HPV-related (HPV DNA-positive and/or p16 positive) SCCUP was calculated for all the SCCUP, initial SCCUP, suspected definitive SCCUP, and true definitive SCCUP whenever a minimum of 10 cases of each category was identified. In addition, data concerning patients' diagnostic work-up, the HPV detection methods, and the correlations between HPV-status, the localization of the occult primary tumor, and the clinical outcome were also extracted. Eighteen retrospective cohort studies, assessing a total of 659 patients, met the inclusion criteria. The overall median prevalences of HPV-DNA(pos), of p16(pos), and of positivity for both HPV markers were, respectively, 37.0, 48.5, and 36.0 %. Patients with diagnosis of initial SCCUP had overall median prevalences of HPV-DNA(pos), of p16(pos), and of positivity for both HPV markers, respectively, of 81.8, 86.2, and 80.8 %. The data uncovered by this systematic review confirm that SCCUP is frequently causally associated to HPV-driven oropharyngeal squamous cell carcinomas. This finding supports the view that HPV-status could be routinely assessed in SCCUP patients as it may lead to identifying the primary tumor and the decision to de-escalate treatment.

Do 18F-FDG PET/CT parameters in oropharyngeal and oral cavity squamous cell carcinomas indicate HPV status?

OBJECTIVE

The aim of this study was to explore the relationship of PET/CT parameters with human papillomavirus (HPV) status of oropharyngeal (OP) and oral cavity (OC) squamous cell carcinomas (SCCs).

PATIENTS AND METHODS

We retrospectively reviewed 39 patients with OC and OP-SCC who underwent staging 18F-FDG PET/CT. PET/CT parameters were measured for the primary tumor and the hottest involved node, including SUV max, SUV mean, SUV peak, metabolic tumor volume, total lesion glycolysis, standardized added metabolic activity (SAM), and normalized SAM. Patient characteristics were compared between HPV positive (HPV+) and negative (HPV-) groups. Receiver operating characteristic analysis was used to dichotomize PET/CT parameters into high and low. Logistic regression models predicting HPV status were fit for each PET/CT parameter.

RESULTS

The HPV+ group was composed of 18 patients all with OP-SCC; the HPV- group consisted of 21 patients, 4 OP cancer patients and 17 OC cancer patients. The HPV+ group had a higher proportion of N2 stage (94% vs 43%; P < 0.001). Nodal PET/CT parameters were higher in the HPV+ group (P < 0.01); this difference was not present for the primary lesion. After adjusting for sex and age, the association of higher nodal SUV max (odds ratio [OR], 9.67), SUV mean (OR, 10.48), SUV peak (OR 9.67), metabolic tumor volume (OR, 14.52), total lesion glycolysis (OR, 11.84), and SAM, normalized SAM (OR, 16.21) with HPV+ status remained statistically significant (P < 0.05).

CONCLUSIONS

Nodal PET/CT parameters predict HPV status. High nodal FDG uptake should raise suspicion for positive HPV status in the evaluation of the primary lesion.

Approach to metastatic carcinoma of unknown primary in the head and neck: squamous cell carcinoma and beyond

Metastatic carcinoma to cervical lymph nodes presenting as an unknown primary is quite common. In most cases, the primary site is ultimately identified. Carcinomas that remain of unknown primary after a thorough search are uncommon. This review will focus on those cases that initially present as unknown primaries, since this is the setting in which pathologists first encounter these cases and in which they play an important role in guiding patient management. Most are squamous cell carcinomas, the majority of which are human papillomavirus (HPV)-related and originate in the palatine tonsils and base of tongue. HPV-related oropharyngeal squamous cell carcinomas are increasing in incidence and have unique clinical and pathologic features that make them particularly likely to present as an unknown primary. Understanding these features has led to improved detection of the primary tumors. Further, even when the primary tumor is not found, prognosis is very dependent on characterization of the tumor HPV status. Papillary thyroid carcinomas may also initially present without a known or clinically detectable primary, either as a neck mass or incidentally in a neck dissection performed for another indication. The latter is a very indolent disease. Finally, primary salivary gland carcinomas may mimic an unknown primary and need to be distinguished from cutaneous metastases to the parotid gland, which may present without a recognized skin tumor. Here, we review the clinical and pathologic features of these entities and provide a systematic approach to their diagnosis.

The use of ultrasound in the search for the primary site of unknown primary head and neck squamous cell cancers

BACKGROUND

Although human papillomavirus detection in cervical lymph nodes of head and neck squamous cell cancers (HNSCC) of unknown primary site (UP) is indicative of a primary tumor of the oropharynx (OP), localization can remain elusive. Therefore, we investigated ultrasonography (US) for the identification of the primary tumor.

METHODS

Eligible cases had HNSCC of UP after evaluation by a head and neck surgical oncologist. Controls were healthy volunteers. Transcervical and intraoral ultrasonography was performed by a standard protocol using convex (3.75-6.0 MHz and 5-7.5 MHz) transducers. US findings were compared with operative examination (exam under anesthesia, direct laryngoscopy) and biopsies. The primary outcome of interest was the presence or absence of a lesion on US.

RESULTS

10 cases and 20 controls were enrolled. PET/CT scans were negative/nonspecific (9), or suspicious (1) for a primary lesion. On US, predominantly hypoechoic (9 of 10) lesions were visualized consistent with base of tongue (n=7) or tonsil (n=3) primary tumors. On operative examination, 5 of 10 were appreciated. Two additional primaries were confirmed with biopsies "directed" by preoperative US. This represents an overall diagnostic rate of 70%, which is 20% higher than our detection rate for 2008-2010. The three cases in which a suspicious lesion was visualized on US, yet remained UP despite further interventions, could represent false positives, misclassification or operator variability. No lesions were suspected among the controls.

CONCLUSION

Ultrasound has promise for detection of UPs of the OP and therefore warrants further investigation.

Surgically treated oropharyngeal cancer: risk factors and tumor characteristics

PURPOSE

To assess risk factors of patients with oropharyngeal squamous cell carcinoma in the Munich area of Southern Germany in relation to human papillomavirus (HPV) association of the tumors. To demonstrate differences in tumor characteristics and their impact on adjuvant treatment.

METHODS

Between November 2010 and July 2013, patients were prospectively interviewed for risk factors before they underwent surgical resection of their tumors. HPV association was evaluated by p16 immunohistochemistry; tumor characteristics and type of adjuvant treatment were recorded. Follow-up data were collected after a median follow-up of 12.1 month.

RESULTS

In contrast to many recent studies, we could not detect any difference in overall age and age at sexual debut between p16-positive and p16-negative patients. P16-negative patients are characterized by a more intensive tobacco and alcohol use, a more abusive way of consumption, less nonoral and less oral sex partners. P16-positive patients had a significantly higher risk of lymph node metastases, but nevertheless a significant lower risk to recur or to die. No difference in the incidence of synchronous second primary tumors was seen. P16-positive patients generally received a more aggressive adjuvant treatment because of more frequently involved lymph nodes.

CONCLUSION

Lifestyle risk factors such as smoking, drinking, and sexual habits were independent from age, but showed marked differences between the p16-positive and p16-negative group. Since p16-positive patients were treated more aggressively, it is not possible to distinguish whether the better outcome of HPV-positive patients is a result of less aggressive cancers or more aggressive treatment. With regard to the ongoing debate about treatment deintensification, we should keep in mind that the survival of HPV-positive cancer patients is not 100 %.

The clinical impact of HPV tumor status upon head and neck squamous cell carcinomas

Human papillomavirus (HPV) is etiologically responsible for a distinct subset of head and neck squamous cell cancers (HNSCCs). HPV-positive HNSCCs (HPV-HNSCCs) most commonly arise from the oropharynx and are responsible for the increasing incidence of oropharyngeal SCC (OSCC) in the United States (US) and abroad. HPV-positive OSCC (HPV-OSCC) has a unique demographic and risk factor profile and tumor biology. HPV-OSCC patients tend to be white, younger, and have a higher cumulative exposure to sexual behaviors as compared with HPV-negative OSCC patients. HPV-positive tumor status also significantly improves survival, and is indeed the single strongest prognostic factor for OSCC. The mechanisms that underlie the improved prognosis conferred by HPV-positive disease are unknown. The purpose of this review is to describe the clinical impact of HPV status in HNSCC, particularly in OSCC, both in terms of the unique clinic-demographic profile and prognostic implications.