Distribution of sentinel nodes from parotid tumors-A feasibility study.

BACKGROUND: Optimum management of the N0 neck is unresolved in parotid salivary gland cancer. Sentinel node biopsy (SNB) can reliably detect microscopic lymph node metastasis and its´ clinical use is increasing for head and neck tumors. The object of this study was to establish whether the technique is applicable to detect distribution of sentinel nodes for parotid tumors. MATERIALS AND METHODS: Prosepective observational study in 30 patients with benign or low-grade T1-T2N0 malignant tumors in the parotid gland planned for surgical treatment. Distribution of SN was detected with a preoperative ultrasound-guided peritumoral injection with a technetium-99 (Tc-99 m) laballed tracer followed by a SPECT-CT and intraoperative measurement in the neck and parotidal tissue. In patients with cytologically suspected malignant tumor or highly unclerar cytology, SNB was also performed. RESULTS: Sentinel nodes (SNs) were detected in 26/30 cases. Out of these, 7 presented with only one SN, whereas multiple sentinel nodes where detected in 19 cases. No SNs were found in neck level 1. SN was detected in level 5 independent of tumor location within the parotid gland. An intraparotidal distribution of SNs was more frequent in larger tumors. CONCLUSIONS: The use of SN-technique in the planning of surgical treatment of parotid tumors seems feasible. It may be of clinical value for patients with parotid cancer to enable a more accurate staging and to detect occult metastasis in the SNs within the parotid as well as in the neck, enabaling the possibility to surgically remove all positive SNs at primary surgery and with reduced surgical morbidity.

Regulatory B cells producing IL-10 are increased in human tumor draining lymph nodes.

The contribution of different immune cell subsets, especially T cells, in anti-tumor immune response is well established. In contrast to T cells, the anti-tumor contribution of B cells has been scarcely investigated. B-cells are often overlooked, even though they are important players in a fully integrated immune response and constitute a substantial fraction of tumor draining lymph nodes (TDLNs) known also as Sentinel Nodes. In this project, samples including TDLNs, non-TDLNs (nTDLNs) and metastatic lymph nodes from 21 patients with oral squamous cell carcinoma were analyzed by flow cytometry. TDLNs were characterized by a significantly higher proportion of B cells compared with nTDLNs (P = .0127). TDLNs-associated B cells contained high percentages of naïve B cells, in contrary to nTDLNs which contained significantly higher percentages of memory B cells. Patients having metastases in TDLNs showed a significantly higher presence of immunosuppressive B regulatory cells compared with metastasis-free patients (P = .0008). Elevated levels of regulatory B cells in TDLNs were associated with the advancement of the disease. B cells in TDLNs were characterized by significantly higher expression of an immunosuppressive cytokine-IL-10 compared with nTDLNs (P = .0077). Our data indicate that B cells in human TDLNs differ from B cells in nTDLNs and exhibit more naïve and immunosuppressive phenotypes. We identified a high accumulation of regulatory B cells within TDLNs which may be a potential obstacle in achieving response to novel cancer immunotherapies (ICIs) in head and neck cancer.

Sentinel node-assisted neck dissection in advanced oral squamous cell carcinoma-A new protocol for staging and treatment.

BACKGROUND: Sentinel lymph node biopsy (SLNB) is used to improve the staging of and guide treatment in patients with early-stage T1-T2 N0 oral squamous cell carcinoma (OSCC). The role of sentinel nodes (SNs) and the use of SN-technique in advanced OSCC (T3-T4 and/or N+) remain to be evaluated. This study investigates the nodal drainage and the rate of positive SNs (SNs+) in all stages of OSCC. MATERIALS AND METHODS: In total, 85 patients with T1-T4 OSCC diagnosed 2019-2021 were included. We used a prolonged interval between peritumoral injection of radionuclide and SPECT-CT to include all SNs. RESULTS: Patients with advanced OSCC presented a higher proportion of contralateral lymphatic drainage and a higher rate of SN+ compared to patients with early-stage disease. T3-T4 and N+ tumors presented a tendency for a higher rate of contralateral lymphatic drainage compared to T1-T2 and N0 tumors (p = 0.1). The prevalence of positive nodes (SNs+) was higher among patients with advanced disease, T3-T4 versus T1-T2 (p = 0.0398). CONCLUSION: SN-assisted ND enables identification and removal of all SNs + and has the potential for more accurate staging and could possibly give prognostic advantages regarding regional recurrence for all OSCC patients, especially among those with advanced disease. The precise localization of the SNs + also suggests that a more individualized ND approach might be possible in the future even for patients with advanced OSCC.

Tumour-draining lymph nodes in head and neck cancer are characterized by accumulation of CTLA-4 and PD-1 expressing Treg cells.

INTRODUCTION: High Tregs infiltration within the tumour microenvironment (TME) of various cancers shows a positive correlation with poor prognosis. Despite the fact that tumour draining lymph nodes (TDLNs) are recognized as key organs playing a crucial role in response to immunotherapy and modulating anti-cancer immunity, the distribution of Tregs and their role in TDLNs remain uncertain thus far. The purpose of this project is to investigate the density of Tregs in TDLNs and non-TDLNs and their expression of immune checkpoint molecules - PD-1 and CTLA-4. METHODS: Samples including TDLNs, non-TDLNs and metastatic lymph nodes (LNs) from 23 patients with oral squamous cell carcinoma (OSCC) were analyzed by multicolour flow cytometry with a focus on Tregs population and expression of CTLA-4 and PD-1. RESULTS: TDLNs and metastatic LNs were characterized by a significantly higher infiltration of Tregs defined as CD4+FoxP3+CD25highCD127low cells and significantly higher expression of CTLA-4 and PD-1 on Tregs compared with non-TDLNs. Tregs in TDLNs and metastatic LNs co-expressed CTLA-4 and PD-1 abundantly. High expression of these immune check-point molecules correlated with positive N-stage but not with T-stage. CONCLUSION: TDLNs and metastatic LNs are characterized by a high accumulation of Tregs expressing high levels of CTLA-4 and PD-1. High infiltration of Tregs can be a potential driver of an immunosuppressive milieu in TDLNs that can, in turn, favour cancer progression. High accumulation of Tregs expressing CTLA-4 and PD-1 in TDLNs is associated with lymph node involvement, but not with the size of the primary tumour.

CD4+ and CD8+ T cells in sentinel nodes exhibit distinct pattern of PD-1, CD69, and HLA-DR expression compared to tumor tissue in oral squamous cell carcinoma.

Anticancer immunotherapies have revolutionized cancer management, yet the effect of systemic anti-programmed cell death protein 1 (PD-1) treatment is predominantly studied in tumor-infiltrating lymphocytes (TILs). Its impact on PD-1 expressing cells in tumor-draining lymph nodes (TDLNs) is not well understood and yet to be explored. Thus, further research aiming for better understanding of the PD-1 pathway not only in tumor tissue but also in TDLNs is warranted. In this study, we investigated the expression of PD-1, CD69, and HLA-DR on CD4+ and CD8+ T cells by flow cytometry analysis of peripheral blood mononuclear cells (PBMCs), TDLNs, and tumor samples from patients with oral squamous cell carcinoma (OSCC). Our data showed that both helper and cytotoxic T lymphocytes in OSCC tissue were highly activated and expressed high level of PD-1 (over 70% positivity). Lymphocytes in TDLNs and peripheral blood expressed significantly lower levels of PD-1 and other activation markers compared to TILs. Moreover, we demonstrated that a significant fraction of PD-1 negative TILs expressed high levels of human leukocyte antigen - DR isotype and CD69. In contrast, PD-1 negative cells in TDLNs and PBMCs scarcely expressed the aforementioned activation markers. Furthermore, we proved that patients with a high percentage of CD3+ PD-1+ cells in tumor-draining lymph nodes had significantly lower disease-free and overall survival rates (log-rank test P = .0272 and P = .0276, respectively). Taken together, we proved that flow cytometry of lymph nodes in OSCC is feasible and may be used to investigate whether PD-1 levels in TDLNs correspond with survival and potentially with response to anti-PD-1 therapy. Such knowledge may ultimately help guide anti-PD-1 treatment.

Human papillomavirus and infiltration of CD8- and Foxp3-positive immune cells in sinonasal inverted papillomas.

Background: Sinonasal inverted papilloma (IP) is a benign tumor with a high risk of local recurrence and a potential to malignify and Human papillomavirus (HPV) has been suggested an etiological factor. p16INK4a (p16) overexpression is considered a surrogate marker for HPV, but whether p16 and HPV correlate to IP is uncertain. Besides, a prognostic role of tumor infiltrating lymphocytes (TILs) are observed in many tumors, however their role in IP is sparsely studied. Aims/objectives: We hence analyzed IPs for the presence and the prognostic role of HPV and p16 overexpression together with CD8+ and FoxP3+ TILs in a population-based study. Material and methods: 98 IP patients diagnosed 2001-2010 were identified from the Swedish Cancer Registry and analyzed for HPV by PCR and p16, CD8 and FoxP3 was by immunohistochemistry. Results: In total, 12.2% of the IPs were HPV-positive (nine HPV-11, two HPV-6 and one HPV-45). Patients with HPV-positive lesions were younger (p = .003) and tended to present with more dysplasia. No correlation was observed between TILs and prognosis. Conclusions and significance: Our data suggests that patients with HPV-positive IPs present with different clinical characteristics, suggesting possibly different disease entities. Moreover, recurrences may occur >5 years, which should be considered in the follow-up.

Incidence of IP and risk of malignant transformation in the Swedish population 1960-2010.

The true incidence of inverted papilloma (IP) is not yet known. From hospital-based studies, its incidence has been estimated to approximately 0.5/100,000 person years. Earlier hospital case studies have shown that IP can undergo a malignant transformation in 1-53 %. The frequency of its malignant transformation on a population basis is unknown. To our knowledge, no standardised incidence ratio (SIR) has been reported for malignancies among IPs. This study aims to investigate these incidences on a population basis. Using the data from the Swedish Cancer Registry (SCR), we have identified patients with IP and patients with Squamous Cell Carcinoma (SCC) diagnosed between 1960 and 2010 in Sweden. Incidence of IP and incidence of SCC among patients with IP and SIR were analyzed. Eight hundred and fourteen patients with IP were identified. The incidence of IPs reported to the SCR increased from 1960 to 2010. In this cohort, SCC was overrepresented, as compared with the general population. The incidence of IP in the Swedish population seems to have increased.

Sinonasal malignancies in Sweden 1960-2010; a nationwide study of the Swedish population.

INTRODUCTION: Sinonasal malignancies (SNM) are rare and the prognosis is generally poor. Recently, a change in incidence for SNM has been reported. In this study, we investigated population-based trends for SNM in Sweden. METHODS: We identified 3,221 patients from the Swedish National Cancer Registry diagnosed with primary malignancies arising from the nasal cavity, paranasal sinuses, or both, during the period 1960 through 2010. Incidence, gender and age, anatomical sites and relative survival were investigated. RESULTS: The incidence for SNM decreased except for sinonasal malignant melanoma (SNMM) and adenoid cystic cancer (even though a very small group) during the study period. More than 50 % of the malignancies involved the nasal cavity. The five-year relative survival was highest for adenoid cystic cancer followed by adenocarcinoma. SNMM and undifferentiated carcinoma had the poorest prognosis. CONCLUSION: We found that the incidence for SNM has decreased during the study period 1960 through 2010, except for SNMM that has increased.