The role of CSTF2 in cancer: from technology to clinical application

A protein called cleavage-stimulating factor subunit 2 (CSTF2, additionally called CSTF-64) binds RNA and is needed for the cleavage and polyadenylation of mRNA. CSTF2 is an important component subunit of the cleavage stimulating factor (CSTF), which is located on the X chromosome and encodes 557 amino acids. There is compelling evidence linking elevated CSTF2 expression to the pathological advancement of cancer and on its impact on the clinical aspects of the disease. The progression of cancers, including hepatocellular carcinoma, melanoma, prostate cancer, breast cancer, and pancreatic cancer, is correlated with the upregulation of CSTF2 expression. This review provides a fresh perspective on the investigation of the associations between CSTF2 and various malignancies and highlights current studies on the regulation of CSTF2. In particular, the mechanism of action and potential clinical applications of CSTF2 in cancer suggest that CSTF2 can serve as a new biomarker and individualized treatment target for a variety of cancer types.

Combination therapy for pancreatic cancer: anti-PD-(L)1-based strategy

Mortality associated with pancreatic cancer is among the highest of all malignancies, with a 5-year overall survival of 5-10%. Immunotherapy, represented by the blocking antibodies against programmed cell death protein 1 or its ligand 1 (anti-PD-(L)1), has achieved remarkable success in a number of malignancies. However, due to the immune-suppressive tumor microenvironment, the therapeutic efficacy of anti-PD-(L)1 in pancreatic cancer is far from expectation. To address such a fundamental issue, chemotherapy, radiotherapy, targeted therapy and even immunotherapy itself, have individually been attempted to combine with anti-PD-(L)1 in preclinical and clinical investigation. This review, with a particular focus on pancreatic cancer therapy, collects current anti-PD-(L)1-based combination strategy, highlights potential adverse effects of accumulative combination, and further points out future direction in optimization of combination, including targeting post-translational modification of PD-(L)1 and improving precision of treatment.

Assessment Criteria and Clinical Implications of Extranodal Extension in Head and Neck Cancer

Tumor breaching the capsule of a lymph node is termed extranodal extension (ENE). It reflects aggressiveness of a tumor, creates anatomic challenges for disease clearance, and increases the risk of distant metastasis. Extranodal extension can be assessed on a pathology specimen, by radiology studies, and by clinical examination. Presence of ENE in a pathology specimen has long been considered a high-risk feature of disease progression and would ordinarily benefit from the addition of chemotherapy to adjuvant radiotherapy. Although the eighth edition of the Union for International Cancer Control/American Joint Committee on Cancer stage classification dichotomizes pathologic ENE according to its presence or absence, emerging evidence suggests that the extent of a pathologic ENE may provide additional value for risk stratification to guide adjuvant therapy. Recent data suggest that the prognostic importance of pathologic ENE is also applicable for HPV-associated head and neck squamous cell carcinoma. In addition, compelling data demonstrate that indisputable radiologic ENE is a powerful risk stratification tool to identify patients at high risk for treatment failure, especially distant metastasis, applicable for both HPV-positive and HPV-negative head and neck squamous cell carcinoma. However, the definition and taxonomy of radiologic ENE requires standardization. The goal of this review is to clarify the contemporary understanding of the prognostic implications of ENE in head and neck squamous cell carcinoma, present the nuances of what is presently known and unknown, and elucidate how to classify ENE pathologically and radiologically with an understanding of the strengths and weaknesses of each approach. Finally, with the development of several risk stratification methods, the relative role of ENE and other prognostic schema will be explored.

Nodal staging convergence for HPV- and HPV+ oropharyngeal carcinoma

BACKGROUND

Modern disease staging systems have restructured human papillomavirus (HPV)-negative (HPV-) and HPV-positive (HPV+) oropharyngeal carcinoma (OPC) into distinct pathologic nodal systems. Given that quantitative lymph node (LN) burden is the dominant prognostic factor in most head and neck cancers, we investigated whether HPV- and HPV+ OPC warrant divergent pathologic nodal classification.

METHODS

Multivariable Cox regression models of OPC surgical patients identified via U.S. cancer registry data were constructed to determine associations between survival and nodal characteristics. Nonlinear associations between metastatic LN number and survival were modeled with restricted cubic splines. Recursive partitioning analysis (RPA) was used to derive unbiased nodal schema.

RESULTS

Mortality risk escalated continuously with each successive positive LN in both OPC subtypes, with analogous slope. Survival hazard increased by 18.5% (hazard ratio [HR], 1.19 [95% CI, 1.16-1.21]; P < .001) and 19.1% (HR, 1.19 [95% CI, 1.17-1.21]; P < .001), with each added positive LN for HPV- and HPV+ OPC, respectively, up to identical change points of 5 positive LNs. Extranodal extension (ENE) was an independent predictor of HPV- OPC (HR, 1.55 [95% CI, 1.20-1.99]; P < .001) and HPV+ OPC (HR 1.73 [95% CI, 1.36-2.20]; P < .001) mortality. In RPA for both diseases, metastatic LN was the principal nodal covariate driving survival, with ENE as a secondary determinant. Given the similarities across analyses, we propose a concise, unifying HPV-/HPV+ OPC pathologic nodal classification schema: N1, 1-5 LN+/ENE-; N2, 1-5 LN+/ENE+; N3, >5 LN+.

CONCLUSION

HPV- and HPV+ OPC exhibit parallel relationships between nodal characteristics and relative mortality. In both diseases, metastatic LN number represents the principal nodal covariate governing survival, with ENE being an influential secondary element. A consolidated OPC pathologic nodal staging system that is based on these covariates may best convey prognosis.

LAY SUMMARY

The current nodal staging system for oropharyngeal carcinoma (OPC) has divided human papillomavirus (HPV)-negative (HPV-) and HPV-positive (HPV+) OPC into distinct systems that rely upon criteria that establish them as separate entities, a complexity that may undermine the core objective of staging schema to clearly communicate prognosis. Our large-scale analysis revealed that HPV- and HPV+ pathologic nodal staging systems in fact mirror each other. Multiple analyses produced conspicuously similar nodal staging systems, with metastatic lymph node number and extranodal extension delineating the highest risk groups that shape prognosis. We propose unifying HPV- and HPV+ nodal systems to best streamline prognostication and maximize staging accuracy.

Potential therapeutic implications of the new tumor, node, metastasis staging system for human papillomavirus-mediated oropharyngeal cancer

PURPOSE OF REVIEW

The 8th edition tumor, node, metastasis (TNM) classification (TNM-8) introduced a new classification for human papillomavirus (HPV)-mediated oropharyngeal carcinoma (HPV+ OPC). This review summarizes its potential therapeutic implications focusing on literature published since 2018.

RECENT FINDINGS

The following are active research areas involved in clinical care and therapy relevant to TNM-8: tumor HPV testing and its clinical implications; stage I disease: treatment selection and lessons learned from recent deintensification trials; emerging strategies addressing stage II and III disease.

SUMMARY

The TNM-8 classification depicts prognosis of HPV+ OPC much more reliably compared with TNM-7. Among the advantages in outcome comparison and stratification for clinical trial entry and conduct, it also enables more satisfactory individual patient consultation to adequately estimate prognosis, and facilitates clinical and translational research. However, clinicians must remain mindful that the TNM classification is not a guideline for treatment but, instead, provides a framework for clinical research and treatment decision-making. The TNM-8 has potential to improve risk-tailored treatment algorithms for HPV+ OPC including selection of treatment modality (primary trans-oral surgery vs. radiotherapy, addition of chemotherapy) and adjusting the intensity of approaches. To realize these goals fully, it is apparent that the TNM-8 needs to evolve further.

Summary from an international cancer seminar focused on human papillomavirus (HPV)-positive oropharynx cancer, convened by scientists at IARC and NCI

Cancer of the oropharynx has attracted considerable attention in recent years given: (1) an increasing incidence in selected populations over the past three decades; (2) the discovery of human papillomavirus (HPV) infection as the driver of the increase, as opposed to the traditional risk factors such as tobacco (smoking and chewing) and alcohol; and (3) the promise of new prevention and treatment strategies. As a result of such developments, the International Agency for Research on Cancer (IARC) and the US National Cancer Institute (NCI), convened the fourth Cancer Seminar meeting in November 2018 to focus on this topic. This report summarizes the proceedings: a review of recent science on the descriptive epidemiology, etiology, biology, genetics, early detection, pathology and treatment of HPV-positive oropharyngeal cancer, and the formulation of key research questions to be addressed.

A review of the 8th edition of the AJCC staging system for oropharyngeal cancer according to HPV status

Background

The incidence of oropharyngeal squamous cell carcinoma (OPSCC) has increased substantially in recent decades, particularly p16-positive human papillomavirus (HPV)-related OPSCC, which has risen by 50% in western countries. HPV-positivity is the most favourable non-anatomic predictor of oropharyngeal cancer outcomes, which underscores the importance of incorporating this variable into the cancer staging system.

Methods

In the present article, we review the differences between the 7th and 8th editions of the AJCC staging system, with particular focus on the role of HPV-positivity in patients with head and neck cancer.

Results

In the previous edition (7th edition) of the AJCC/UICC manual, HPV status and its correlation with nodal metastasis were not considered, thereby leading to incorrect lymph node (N) staging and, potentially, inadequate treatment and worse outcomes. The 8th edition of the AJCC manual addresses these issues, providing more accurate discrimination between groups and better risk stratification in patients with HPV-positive OPSCC. In the future, additional adjustments are likely to be needed, such as unification of the pathological and clinical staging models.

Conclusions

The new staging system is substantially more accurate than the previous system and should be widely adopted in routine clinical practice.

Deintensification of treatment for human papillomavirus-related oropharyngeal cancer: Current state and future directions

Human papillomavirus (HPV)-related oropharyngeal squamous cell cancer (OPSCC) has emerged as a distinct clinical entity of head and neck cancer with expected high survival. This recognition has led to the investigation of whether a population of patients can be identified who can safely undergo treatment de-escalation, in an effort to minimize long-term treatment toxicity while maintaining excellent survival. The purpose of this review is to describe the rationale for treatment deintensification for HPV-related OPSCC, summarize available results from published clinical trials, explore the methods by which risk groups are assigned, and provide context for the multitude of clinical trials that are currently underway.

Critical Changes in the Staging of Head and Neck Cancer

The many changes made to the head and neck (HN) chapters of the eighth edition of the American Joint Committee on Cancer (AJCC) and Union for International Cancer Control (UICC) cancer staging manuals have resulted in confusion from clinicians and radiologists. These changes have even raised concerns for validity. In prior staging manual updates, the changes made largely provided simplification of more complex staging details. The current eighth edition of the AJCC/UICC staging manuals introduced greater granularity to HN tumor staging. This reflects the current understanding of pathophysiology of these cancers and is necessary to create a more accurate prognosis for these patients. The most commonly encountered example of manual changes is the separate staging of viral-associated oropharyngeal squamous cell carcinoma from tobacco and alcohol use-associated squamous cell carcinoma. While anatomic imaging is critical for HN cancer staging, and frequently outweighs clinical examination, some changes to staging make it impossible for a stage to be assigned until surgical resection is performed. In all, the AJCC/UICC eighth edition changes, the impact on radiologists, and the rationale behind the changes will be discussed. Additionally, opportunities for radiologists to contribute to research that may influence the next edition of AJCC/UICC cancer staging manuals will be proposed. Keywords: Head/Neck, Oncology, Pharynx, Staging © RSNA, 2020.

Validation of NRG oncology/RTOG-0129 risk groups for HPV-positive and HPV-negative oropharyngeal squamous cell cancer: Implications for risk-based therapeutic intensity trials

BACKGROUND

Radiation Therapy Oncology Group (RTOG)-0129 recursive partitioning analysis was the basis for risk-based therapeutic intensification trials for oropharyngeal cancer (OPC). To the authors' knowledge, the question of whether RTOG-0129 overall survival (OS) estimates for low-risk, intermediate-risk, and high-risk groups are similar in other data sets or applicable to progression-free survival (PFS) is unknown. Therefore, the authors evaluated whether survival differences between RTOG-0129 risk groups persist at 5 years, are reproducible in an independent clinical trial, and are applicable to PFS, and whether toxicities differ across risk groups.

METHODS

Prospective randomized clinical trials were analyzed retrospectively. RTOG-0129 evaluated standard versus accelerated fractionation radiotherapy concurrent with cisplatin. RTOG-0522 compared the combination of cisplatin and accelerated fractionation with or without cetuximab. Patients with OPC with available p16 status and tobacco history were eligible.

RESULTS

There was a total of 260 patients and 287 patients, respectively, from RTOG-0129 and RTOG-0522, with median follow-ups for surviving patients of 7.9 years (range, 1.7-9.9 years) and 4.7 years (range, 0.1-7.0 years), respectively. Previous OS differences in RTOG-0129 persisted at 5 years. In RTOG-0522, the 5-year OS rates for the low-risk, intermediate-risk, and high-risk groups were 88.1%, 69.9%, and 45.1%, respectively (P for trend, <.001). The 5-year PFS rates for the same 3 groups were 72.9%, 56.1%, and 42.2%, respectively. In RTOG-0522 among a subgroup of patients considered to be at very good risk (p16-positive disease, smoking history of ≤10 pack-years, and classified with T1-T2 disease with ipsilateral lymph nodes measuring ≤6 cm or T3 disease without contralateral or >6 cm lymph nodes), the 5-year OS and PFS rates were 93.8% and 82.2%, respectively. Overall rates of acute and late toxicities were similar by risk group.

CONCLUSIONS

RTOG-0129 risk groups persisted at 5 years and were reproducible in RTOG-0522. However, there was variability in the estimates. These data underscore the importance of long-term follow-up and appropriate patient selection in therapeutic deintensification trials.

From presumed benign neck masses to delayed recognition of human papillomavirus-positive oropharyngeal cancer

OBJECTIVES/HYPOTHESIS

To describe patients with delayed diagnosis of human papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV-OPC) after initial incorrect diagnosis of branchial cleft cyst or nondiagnostic workup of unilateral neck mass.

STUDY DESIGN

Retrospective case series.

METHODS

Patients with delayed diagnosis of HPV-OPC after initial nondiagnostic workup for unilateral neck mass were eligible. Medical record abstraction was performed to describe clinical characteristics at initial presentation and later diagnosis of HPV-OPC. To estimate nodal growth rates, the short axis diameter of the lymph nodes was determined from imaging reports.

RESULTS

Six patients met eligibility criteria. After a median interval of 42 months (range, 3 months-7 years) from initial presentation with unilateral neck mass, patients were diagnosed with HPV-OPC. At the time of HPV-OPC diagnosis, five were AJCC eighth edition overall stage I, and one was stage II. Primary tumors were T0 or T1 in the majority (83.3%, n = 5). Among five patients with available serial imaging, despite diagnostic delay, three of five still had a single lymph node without involvement of additional nodes, whereas the remaining two developed additional suspicious nodes (ipsilateral and contralateral). Two of five developed evidence of extranodal extension. Median lymph node growth was 9.5% per year (range, -6% to 32%).

CONCLUSIONS

Although the natural history of HPV-OPC is not well understood, this case series suggests that it can be slow growing and mimic benign processes, leading to diagnostic delays. Adults presenting with neck masses should undergo complete diagnostic evaluation.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:392-397, 2020.

Data Set for the Reporting of Carcinomas of the Nasopharynx and Oropharynx: Explanations and Recommendations of the Guidelines From the International Collaboration on Cancer Reporting

The International Collaboration on Cancer Reporting was established to internationally unify and standardize the pathologic reporting of cancers based on collected evidence, as well as to allow systematic data collection across institutions and countries to guide cancer care in the future. An expert panel was convened to identify the minimum data set of elements that should be included in cancer reporting from tumors of the nasopharynx and oropharynx. Specifically, there has been a significant change in practice as a result of identifying oncogenic viruses, including human papillomavirus and Epstein-Barr virus, because they preferentially affect the oropharynx and nasopharynx, respectively. For these anatomic sites, when viral association is taken into account, usually reported elements of in situ versus invasive tumor, depth of invasion, and degree of differentiation are no longer applicable. Thus, guidance about human papillomavirus testing in oropharyngeal carcinomas and Epstein-Barr virus testing in nasopharyngeal carcinomas is highlighted. Further, the clinical and the pathologic differences in staging as proposed by the 8th edition of the Union for International Cancer Control are incorporated into the discussion, pointing out several areas of continued study and further elaboration. A summary of the International Collaboration on Cancer Reporting guidelines for oropharyngeal and nasopharyngeal carcinomas is presented, along with discussion of the salient evidence and practical issues.