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

Outcome differences in HPV-driven head and neck squamous cell carcinoma attributable to altered human leukocyte antigen frequencies

Background

Effective immune surveillance requires a functioning immune system and natural killer (NK) and T cells for adequate innate and antigen-specific immune responses critically depending on human leukocyte antigens (HLAs) and haplotypes representing advantageous combinations of HLA antigens. Recently, we reported a link between altered frequencies of HLA alleles and haplotypes and developing head and neck squamous cell carcinoma (HNSCC). Whereas the majority of HNSCCs seem to be related to classical risk factors alcohol and tobacco, a subset of HNSCC and especially oropharyngeal squamous cell carcinoma (OPSCC) were etiologically linked to human papillomavirus (HPV) recently. Here, we demonstrate in HPV-driven (p16-positive high risk-HPV DNA-positive) HNSCC a deviating distribution of HLA antigens and haplotypes and their relevance to outcome.

Methods

Leukocyte DNA of n = 94 HPV-driven HNSCC patients (n = 57 OPSCC, n = 37 outside oropharynx) underwent HLA SSO typing, allowing allele, antigen (allele group), and haplo-typing. Besides comparing these frequencies with those of German blood donors, we analyzed their impact on outcome using Kaplan-Meier plots and Cox proportional hazard regression.

Results

Antigen and haplotype frequencies demonstrate enrichment of rare antigens and haplotypes. The HLA score for unselected HNSCC patients was not predictive for outcome here. However, together with alcohol consumption, tobacco smoking, T category, and extranodal extension of locoregional metastases and treatment applied, eight HLA traits allow for predicting progression-free and tumor-specific survival.

Conclusion

Patients can be categorized into low, intermediate-low, intermediate-high, and high risk groups. Using a new PFS risk score for HPV-driven HNSCC may allow to improve prognostication.

Neck Node Squamous Cell Metastasis from Unknown Primary and Mutagen Sensitivity: A Case Series

Most of the neck node metastases from cancer of unknown primary (CUP) are squamous cell carcinomas (SCCs). The majority of which are human papillomavirus (HPV)-related, frequently show cystic morphology referring to Waldeyer's ring origin. Here, we report four cases of neck node SCCs metastases from CUP. In our institute, 432 patients with head and neck (HN) SCC underwent pretreatment mutagen sensitivity (MS) assay between 1996 and 2006. Among them, 4 patients ≤50 years of age had metastatic cervical nodes from CUP. The primary treatment was cervical node dissection ± radiotherapy. All patients had elevated (>1.0 chromatid break/cell) MS. One male patient died of progressive neck metastasis within 3 years and the 3 female patients are still alive more than 15 years after initial treatment of HPV+ (two) or cystic (one) SCC. Two female patients developed second and third distant site metachronous primary cancers. HPV+ or cystic HNSCC from CUP with elevated MS indicates good outcome. Distant site metachronous cancers of different histologic origins cannot be explained by field cancerization. The clinical significance of elevated MS in neck node SCC metastasis from CUP requires further investigation.

Standardized Diagnostic Workup and Patient-Centered Decision Making for Surgery and Neck Dissection Followed by Risk-Factor Adapted Adjuvant Therapy Improve Loco-Regional Control in Local Advanced Oral Squamous Cell Carcinoma

Background

Standardized staging procedures and presentation of oral squamous cell carcinoma (OSCC) patients in multidisciplinary tumor boards (MDTB) before treatment and utilization of elective neck dissection (ND) are expected to improve the outcome, especially in local advanced LAOSCC (UICC stages III–IVB). As standardized diagnostics but also increased heterogeneity in treatment applied so far have not been demonstrated to improve outcome in LAOSCC, a retrospective study was initiated.

Methods

As MDTB was introduced into clinical routine in 2007, 316 LAOSCC patients treated during 1991-2017 in our hospital were stratified into cohort 1 treated before (n=104) and cohort 2 since 2007 (n=212). Clinical characteristics, diagnostic procedures and treatment modality of patients were compared using Chi-square tests and outcome analyzed applying Kaplan-Meier plots and log-rank tests as well as Cox proportional hazard regression. Propensity scores (PS) were used to elucidate predictors for impaired distant metastasis-free survival (DMFS) in PS-matched patients.

Results

Most patient characteristics and treatment modalities applied showed insignificant alteration. Surgical treatment included significantly more often resection of the primary tumor plus neck dissection, tracheostomy and percutaneous endoscopic gastrostomy tube use. Cisplatin-based chemo-radiotherapy was the most frequent. Only insignificant improved disease- (DFS), progression- (PFS) and event-free (EFS) as well as tumor-specific (TSS) and overall survival (OS) were found after 2006 as local (LC) and loco-regional control (LRC) were significantly improved but DMFS significantly impaired. Cox regression applied to PS-matched patients elucidated N3, belonging to cohort 2 and cisplatin-based chemo-radiotherapy as independent predictors for shortened DMFS. The along chemo-radiotherapy increased dexamethasone use in cohort 2 correlates with increased DM.

Conclusions

Despite standardized diagnostic procedures, decision-making considering clear indications and improved therapy algorithms leading to improved LC and LRC, shortened DMFS hypothetically linked to increased dexamethasone use had a detrimental effect on TSS and OS.