Long-term immune dysfunction after radiotherapy to the head and neck area

The Role of Lymphocyte Recovery Index in Prognosis Prediction for Locally Advanced Cervical Cancer With Radiation-Induced Lymphopenia

BACKGROUND

In patients with locally advanced cervical cancer (LACC) undergoing concurrent chemoradiotherapy (CCRT), the high incidence of radiation-induced lymphopenia significantly affects prognosis. There are significant variations in lymphocyte count (ALC) recovery patterns among patients, and their impact on prognosis remains unclear. This study aims to quantify the lymphocyte recovery patterns by the lymphocyte recovery index (LRI) and evaluate its prognostic value.

METHODS

This study reviewed patients with LACC who had ALCs available within 6 months post-CCRT. Lymphopenia was graded using CTCAE 5.0, and lymphocyte recovery patterns were quantified using LRI (the ratio of ALCs at 6 months post-treatment to baseline ALCs). Cox regression analysis was conducted to assess the correlation between LRI, other clinical factors, and survival. The dose-volume of bone marrow (BM) following pelvic radiotherapy was collected, and measurements of spleen standardized uptake value (SUV) and spleen-to-liver SUVmax ratio (SLR) were obtained from pre-treatment 18F-FDG PET/CT. Logistic regression analysis was used to identify independent risk factors for LRI.

RESULTS

A total of 180 patients were included retrospectively. During CCRT, 53 patients (29.4%) experienced G4 lymphopenia. The median LRI was 53.4% (range 13.2%-159.4%). Multivariable analysis revealed that LRI, G4 lymphopenia, and FIGO stage were associated with progression-free survival (PFS) and overall survival (OS). Subgroup analysis revealed that the degree of lymphopenia (G4 and G1-3) did not affect the correlation between LRI and PFS (P: 0.001 and 0.011) or OS (P: 0.003 and 0.043). Regarding FIGO stage, the impact of LRI on PFS (p < 0.001) and OS (p < 0.001) was primarily observed in patients with FIGO stage > II. Logistic analysis identified BM-V10 > 96.0% and SLR > 0.90 as independent risk factors for LRI.

CONCLUSION

In patients with LACC after CCRT, the LRI is associated with prognosis. Splenic metabolism and BM irradiation are associated with lymphocyte recovery.

Hypofractionated radiotherapy with simultaneous integrated boost for localized prostate cancer patients: effects on immune system and prediction of toxicity

Background

The other side of radiotherapy (RT), in addition to the cytotoxic effect, is the ability to modulate the immune system in terms of activation or suppression, also depending on the dose and fractionation delivered. This immune RT effect can be detected both locally in the irradiated tumor site and in the peripheral blood. The aim of this study was to assess the consequence of pelvic irradiation on peripheral immune cells and cytokine secretions in localized prostate cancer (PC) patients undergoing pelvic irradiation with a simultaneous moderately hypofractionated prostate/prostate bed boost by Volumetric Modulated Arc Therapy (VMAT). Furthermore, we analyzed whether there was a correlation between these peripheral immune parameters and acute and late genitourinary (GU) and gastrointestinal (GI) toxicity.

Methods

Thirty-eight PC patients were treated with pelvis irradiation (dose per fraction 1.8 Gy) and simultaneous hypofractionated (median dose per fraction: 2.7 Gy) prostate/prostate bed boost. A longitudinal analysis was performed for 12 months on peripheral blood to assess changes in 9 different lymphocyte subpopulations by flow cytometry and 10 circulating cytokines by Multiplex Luminex assay and ELISA.

Results

Our analysis revealed that basal IFN-γ serum values were significantly lower in the definitive (curative intent for patients with prostate) patient group respect to the post-operative one. All the lymphocyte subsets and IFN-α, IFN-β and Il-2 peripheral concentrations displayed significant variations between the different time points considered. The immune cell population that suffers the greatest RT toxicity in the blood was B lymphocyte. We found an interesting correlation between basal TGF-β1 and late GU toxicity. In particular, TGF-β1 concentrations before RT were significantly higher in patients that experienced grade 2-3 of late GU toxicity, respect to grade 0-1. Exploring possible correlations between some clinical/biological findings and radiation planning parameters, we found no statistical significance.

Conclusions

Our study analyzed, in the context of hypofractionated radiotherapy in prostate cancer, different parameters of the peripheral immune system. We have highlighted longitudinally the peripheral behavior of the different lymphocyte subpopulations and of a group of 10 cytokines during the first year after RT. One of the analyzed cytokines, such as TGF-β1, has proven to be promising predictive factor of severe late GU toxicity.

Clinical characteristics and outcomes of persistent bacteremia in patients with head and neck cancer in a tertiary care hospital

Introduction

Compared to other cancers, research on bloodstream infection in head and neck cancer is scarce, lacking comparative studies on persistent versus transient bacteremia outcomes.

Methods

This retrospective survey examined patients with head and neck cancer undergoing blood culture at our center from June 2009 to May 2023. Blood culture-positive cases suspected of infection were divided into persistent bacteremia and transient bacteremia groups. We investigated their clinical, epidemiological, and microbiological features, including risk factors for persistent bacteremia and mortality. The primary outcome was 90-day mortality.

Results

In this 97-patient cohort, 14 (14%) cases were assigned to the persistent bacteremia group. Catheter-related bloodstream infections were the leading cause of infection in both groups, consistently contributing to a high proportion of overall bloodstream infections. The mortality rate was generally higher in the persistent bacteremia group than in the transient bacteremia group (odds ratio [OR], 2.6; 95% confidence interval [CI], 0.6-11.1), particularly in the non-clearance subgroup (OR, 9; 95% CI, 0.5-155.2). Pyogenic spondylitis was a key risk factor for persistent bacteremia, while hypoalbuminemia increased mortality.

Conclusion

In patients with bacteremia and head and neck cancer, persistent bacteremia was associated with higher mortality than was transient bacteremia. Adittionally, bacteremia clearance in persistent bacteremia is thus crucial for prognostic improvement.

Circulating Hsp70 Levels and the Immunophenotype of Peripheral Blood Lymphocytes as Potential Biomarkers for Advanced Lung Cancer and Therapy Failure after Surgery

Lung cancer remains a devastating disease with a poor clinical outcome. A biomarker signature which could distinguish lung cancer from metastatic disease and detect therapeutic failure would significantly improve patient management and allow for individualized, risk-adjusted therapeutic decisions. In this study, circulating Hsp70 levels were measured using ELISA, and the immunophenotype of the peripheral blood lymphocytes were measured using multiparameter flow cytometry, to identify a predictive biomarker signature for lung cancer patients pre- and post-operatively, in patients with lung metastases and in patients with COPD as an inflammatory lung disease. The lowest Hsp70 concentrations were found in the healthy controls followed by the patients with advanced COPD. Hsp70 levels sequentially increased with an advancing tumor stage and metastatic disease. In the early-recurrence patients, Hsp70 levels started to increase within the first three months after surgery, but remained unaltered in the recurrence-free patients. An early recurrence was associated with a significant drop in B cells and an increase in Tregs, whereas the recurrence-free patients had elevated T and NK cell levels. We conclude that circulating Hsp70 concentrations might have the potential to distinguish lung cancer from metastatic disease, and might be able to predict an advanced tumor stage and early recurrence in lung cancer patients. Further studies with larger patient cohorts and longer follow-up periods are needed to validate Hsp70 and immunophenotypic profiles as predictive biomarker signatures.

Effect of lymphoid volume irradiation on radiation-induced lymphopenia in head and neck cancers

PURPOSE

Radiotherapy induces significant and prolonged lymphopenia in head and neck cancer patients with poorer outcomes and reduced survival. Irradiated volumes may be correlated with lymphopenia with a potential impact on immunotherapy efficacy. We assessed associations between volumes treated with radiotherapy and the nadir of the lymphocyte count in patients with head and neck cancer.

MATERIALS AND METHODS

We conducted a monocentric retrospective study in patients with head and neck cancer treated with radiation. Univariate analysis used regression analysis to model nadir lymphocyte count and radiotherapy volumes; multivariate analysis then modelled factors associated with nadir lymphocyte count.

RESULTS

Of the 77 included patients, 97% presented lymphopenia during radiotherapy with an average nadir of 431 cells/mm³ at a median of 40 days after the beginning of treatment. The volume of high-risk radiotherapy and gross tumour volume were correlated with nadir lymphocyte count with a Spearman coefficient of -0.267 (P=0.019) and -0.387 (P=0.001), respectively. After multivariate linear regression, high-risk radiotherapy was significantly associated with nadir lymphocyte count with a regression coefficient of -0.32 (per cubic centimetre) [95% CI=-0.60; -0.03] (P=0.028).

CONCLUSION

High-risk radiotherapy was significantly associated with nadir lymphocyte count in patients with head and neck cancer treated with radiation. Sparing lymphoid volumes from irradiation by elective nodal irradiation or proton therapy may limit lymphopenia and needs to be investigated in combination with immunotherapy.

Decoding the influence of the immune system and immunotherapy targets on carcinomas: A hidden prism in oral cancer therapy

In recent decades, understanding tumorigenesis and the complex interaction between the host and the immune system has been the pillar for significant advances in anticancer therapy. Conventional anticancer therapy (e.g., cut, burn, and cytotoxic drugs) involves multiple targeting of tumor cells. However, the tumor tissue microenvironment can present a dysregulated, stimulating, or subverted immune response which, in turn, reveals pro-tumor activities favoring tumor expansion and progression. Recently, new potential targets have been identified based on immunomodulatory therapies, which are crafted to re-establish the host anti-tumoral immune response. Clinicians should fully understand the intricate interactions between carcinogens, the tumor milieu, the immune system, and traditional anticancer therapies in order to progress and to overcome the refractory/recurrent challenges and morbidity of the disease. Thus, in this article, we highlight the complex milieu of the oral cancer immune response, pointing out potential therapeutic immunotargets for oral squamous cell carcinomas. The impact of traditional anticancer therapy on the immune system is also outlined.

Impact of lymphopenia on efficacy of nivolumab in head and neck cancer patients

INTRODUCTION

Lymphopenia has been correlated with poorer survival in patients with metastatic cancers treated with anti-PD-1 immunotherapy. Treatments such as chemotherapy, surgery or radiotherapy can induce lymphopenia. Radiation-induced lymphopenia is common and prolonged in head and neck cancer (HNSCC) patients. We evaluated the impact of lymphopenia, on efficacy of anti PD-1 nivolumab immunotherapy in HNSCC patients.

METHODS

a multicenter retrospective study included consecutive patients treated with nivolumab for recurrent/metastatic (R/M) HNSCC between January 2017 and June 2019. Lymphopenia was defined as lymphocyte counts below 1000 cells/mm³ upon initiation of nivolumab. Logistical regression was performed on factors associated with lymphopenia and ROC analyses assessed association between lymphopenia and survival.

RESULTS

median age was 65. Of the 100 included patients, 60% had been treated by surgery, 67% had had first-line chemotherapy, and 89% loco-regional radiotherapy, 65% had concurrent chemotherapy with radiotherapy. Lymphopenia occurred in 56 (56%) patients upon initiation of nivolumab, with 29 (29%) patients having radiation-related lymphopenia. Prior locoregional radiotherapy was the only factor associated with lymphopenia upon initiation of nivolumab by logistical regression (OR 0.144 [0.029-0.706], p - 0.017). Lymphopenia upon initiation of nivolumab did not affect progression-free survival (PFS) (p - 0.815), overall survival (OS) (p - 0.783) or disease control rate (DCR) (p - 0.125). Locoregional symptomatology (HR - 2.37 [1.24-4.54], p - 0.009), metastatic symptomatology (HR - 4.74 [2.21-10.15], and persistent lymphopenia under nivolumab (HR 3.96 [1.19-13.17] p - 0.034) were associated with poorer OS in multivariate analysis.

CONCLUSIONS

Lymphopenia upon initiation of nivolumab was not associated with poorer survival in R/M HNSCC patients, but persistence of lymphopenia during immunotherapy might be a prognostic marker of patient survival.

Evaluation of Candidiasis in Upper-Aerodigestive Squamous Cell Carcinoma Patients—A Clinico-Mycological Aspect

Candida is a commensal yeast. It can be infective when the host’s defense mechanism is weakened, as in the case of squamous cell carcinoma patients. We aimed to evaluate the prevalence and clinical mycological manifestation of candidiasis in 150 cancer cases comprised of preoperative and post-operative (with or without radiotherapy) upper aerodigestive squamous cell carcinoma. A total of 150 patients suffering from squamous cell carcinoma of the Upper Aero-Digestive Tract (UADT) were divided into preoperative (n = 48), post-operative without radiotherapy (n = 29) and post-operative with radiotherapy (n = 73). Samples were collected using cotton swabs and cultured. Candida species were identified according to color pigmentation on Candida Differential Agar (CDA) plate. The clinico-mycological association of patients was evaluated by the chi-square test, and 98 out of 150 patients showed the presence of various Candida species. The major species isolated was Candida albicans (53%), followed by Candida tropicalis (16%). There was a significant statistical difference between patients who showed mycological associations and patients who did not have any such association (p = 0.0008). The prevalence of oral candidiasis was found to be 65.33% among total cases of upper aero-digestive squamous cell carcinoma. Chronic erythematous cases of candidiasis were mainly seen in preoperative squamous cell carcinoma cases, whereas the acute erythematous type of candidiasis was mainly seen in post-operative cases who received radiotherapy. The clinicomycological assessment can help to correlate the signs and symptoms with the presence of candidiasis in upper aerodigestive squamous cell carcinoma patients. Meticulous testing and examination can help in the early detection of candidiasis. Future studies are needed to develop advance scientific preventive strategies for high-risk cases.

A Rational Approach to Unilateral Neck RT for Head and Neck Cancers in the Era of Immunotherapy

Radiotherapy plays an important role in the definitive and adjuvant treatment of head and neck squamous cell carcinoma (HNSCC). However, standard courses of radiation therapy may contribute to the depletion of circulating lymphocytes and potentially attenuate optimal tumor antigen presentation that may be detrimental to the efficacy of novel immunotherapeutic agents. This review explores the advantages of restricting radiation to the primary tumor/tumor bed and ipsilateral elective neck as it pertains to the evolving field of immunotherapy.

Bloodstream infections in head and neck cancer patients after curative-intent radiotherapy: a population-based study from the Danish Head and Neck Cancer Group database

BACKGROUND

Patients with head and neck squamous cell carcinoma (HNSCC) undergoing radiotherapy (RT) or chemoradiation (CRT) may become immunocompromised. In this population-based study, we aimed to investigate the risk factors, microbiological aetiologies, prognosis and impact on early non-cancer mortality of bloodstream infections (BSIs) after RT/CRT.

METHODS

Patients with HNSCC of the pharynx, larynx and oral cavity treated with curative-intent RT/CRT in Denmark between 2010 and 2017 and subsequent BSI episodes occurring within 18 months of RT/CRT initiation were identified in national registries.

RESULTS

We included 5674 patients and observed 238 BSIs. Increasing age, stage and performance status were significantly associated with an elevated BSI risk, while sex, smoking and high-grade mucositis were not. Human papillomavirus-positive oropharyngeal cancer patients had a decreased risk. Staphylococcus aureus accounted for 34% of episodes occurring during the first 3 months. The 30-day post-BSI mortality rate was 26% (95% confidence interval: 19-32) and BSIs were involved in 10% of early non-cancer deaths.

CONCLUSION

The risk of BSI development is associated with several patient- and disease-related factors and BSIs contribute considerably to early non-cancer mortality. Empiric antibiotic treatment regimens should prioritise coverage for S. aureus when treating suspected systemic infection in this population.

Radiotherapy in the Era of Immunotherapy With a Focus on Non-Small-Cell Lung Cancer: Time to Revisit Ancient Dogmas?

Radiation-induced immune effects have been extensively deciphered over the last few years, leading to the concept of the dual immune effect of radiotherapy with both immunostimulatory and immunosuppressive effects. This explains why radiotherapy alone is not able to drive a strong anti-tumor immune response in most cases, hence underlining the rationale for combining both radiotherapy and immunotherapy. This association has generated considerable interest and hundreds of trials are currently ongoing to assess such an association in oncology. However, while some trials have provided unprecedented results or shown much promise, many hopes have been dashed. Questions remain, therefore, as to how to optimize the combination of these treatment modalities. This narrative review aims at revisiting the old, well-established concepts of radiotherapy relating to dose, fractionation, target volumes and organs at risk in the era of immunotherapy. We then propose potential innovative approaches to be further assessed when considering a radio-immunotherapy association, especially in the field of non-small-cell lung cancer (NSCLC). We finally propose a framework to optimize the association, with pragmatic approaches depending on the stage of the disease.

Influence of Preoperative Radiation Therapy on the Occurrence of Pharyngocutaneous Fistula After Total Laryngectomy

Introduction

Chemo-radiotherapy (CRT) has increasingly been employed for the treatment of laryngeal cancer at T3 or higher rather than total laryngectomy (TL), in order to preserve the larynx. However, TL is still frequently performed in patients with advanced laryngeal cancer, especially T4 disease. When CRT is performed for advanced cancer, there is a certain rate of residual disease or relapse, and TL is conducted as salvage surgery for those patients, but TL following CRT is associated with a high incidence of postoperative complications.

Objective

The purpose of this study was to investigate the influence of preoperative radiation therapy on the occurrence of postoperative complications of TL, particularly pharyngocutaneous fistula (PCF).

Methods

We retrospectively investigated 142 patients who underwent TL for laryngeal cancer whether postoperative complications were related to a history of radiation therapy or neck dissection. Detailed investigation of the 32 patients who underwent radiation therapy was also conducted.

Results

PCF was significantly higher after radiation therapy. Neck dissection was not related. As the time from radiation therapy to TL decreased, the incidence rate of postoperative PCF increased and the time to closure became significantly longer. Preoperative laboratory tests did not show a significant difference in Hb and Alb, but the lymphocyte count was significantly lower in patients with PCF.

Recurrent HNSCC Harbor an Immunosuppressive Tumor Immune Microenvironment Suggesting Successful Tumor Immune Evasion

PURPOSE

Recurrent tumors (RT) of head and neck squamous cell carcinoma (HNSCC) occur in up to 60%, with poor therapeutic response and detrimental prognosis. We hypothesized that HNSCC RTs successfully evade antitumor immune response and aimed to reveal tumor immune microenvironment (TIME) changes of primary tumors (PT) and corresponding RTs.

EXPERIMENTAL DESIGN

Tumor-infiltrating leukocytes (TIL) of 300 PTs and 108 RTs from two large independent and clinically well-characterized HNSCC cohorts [discovery cohort (DC), validation cohort (VD)] were compared by IHC. mRNA expression analysis of 730 immune-related genes was performed for 18 PTs and RTs after adjuvant chemoradiotherapy (CRT). The effect of chemotherapy and radiation resistance was assessed with an in vitro spheroid/immunocyte coculture model.

RESULTS

TIME analysis revealed overall decrease of TILs with significant loss of CD8⁺ T cells (DC P = 0.045/VC P < 0.0001) and B lymphocytes (DC P = 0.036/VC P < 0.0001) in RTs compared with PTs in both cohorts. Decrease predominantly occurred in RTs after CRT. Gene expression analysis confirmed loss of TILs (P = 0.0004) and B lymphocytes (P < 0.0001) and showed relative increase of neutrophils (P = 0.018), macrophages (P < 0.0001), dendritic cells (P = 0.0002), and mast cells (P = 0.0057) as well as lower overall expression of immune-related genes (P = 0.018) in RTs after CRT. Genes involved in B-lymphocyte functions and number of tertiary lymphoid structures showed the strongest decrease. SPP1 and MAPK1 were upregulated in vivo and in vitro, indicating their potential suitability as therapeutic targets in CRT resistance.

CONCLUSIONS

HNSCC RTs have an immunosuppressive TIME, which is particularly apparent after adjuvant CRT and might substantially contribute to poor therapeutic response and prognosis.

[Mechanisms of radiation-induced lymphopenia and therapeutic impact]

Radiation induced lymphopenia is frequent and can be severe and durable. Although lymphocytes have long been known as highly radiosensitive cells, it is poorly characterized. Radiation-induced lymphopenia seems to affect lymphocyte subpopulations differently and seems to be influenced by radiation modalities. The depth and duration of lymphopenia depend on the location of the irradiation and the volumes of treatment. Importantly, radiation-induced lymphopenia has been associated with poorer prognosis in several tumor types. The knowledge about radiation-induced lymphopenia might lead to a rethinking of the modalities of radiotherapy and new approaches to restore lymphocytes counts.

Concurrent Definitive Immunoradiotherapy for Patients with Stage III-IV Head and Neck Cancer and Cisplatin Contraindication

PURPOSE

Although cisplatin plus radiotherapy is a standard treatment of locally advanced head and neck squamous cell carcinoma (LA-HNSCC), cisplatin contraindication is common. Radiation elicits and promotes tumor-directed immune stimulation, which may potentiate anti-PD-1 therapy. We provide the first efficacy report of combined pembrolizumab and definitive radiotherapy in LA-HNSCC.

PATIENTS AND METHODS

This single-arm, multi-institution, phase II study (NCT02609503) enrolled 29 cisplatin-ineligible patients. Patients received radiotherapy concurrently with three cycles of pembrolizumab 200 mg every 3 weeks followed by three adjuvant cycles. The primary endpoint was a progression-free survival (PFS) of ≥16 months. Correlative studies included peripheral blood flow cytometry and Luminex cytokine profiling.

RESULTS

Reasons for cisplatin ineligibility included otopathy (69.0%), nephropathy (20.7%), and neuropathy (6.9%). With median follow-up of 21 months, estimated 24-month PFS and overall survival rates were 71% (95% confidence interval, 49%-84%) and 75% (51%-88%). The primary PFS endpoint has exceeded the hypothesis and its median has not been reached. Toxicities were typical of radiotherapy; however, high rates of grade 3/4 lymphopenia (58.6%) were observed. Flow cytometry revealed a relative decline in CD4 T cells and B cells, but not CD8 T cells. Upon treatment, frequencies of transitional B cells and tissue-like memory B cells increased, while resting memory B cells decreased. Patients with progression had greater percentages of baseline naïve B cells and fewer marginal zone B cells.

CONCLUSIONS

Pembrolizumab and radiotherapy is efficacious in LA-HNSCC and should be evaluated in a randomized trial. The observed changes in B-cell markers deserve further study both as potential biomarkers and as therapeutic targets.

Care of immunocompromised patients with head and neck cancer during the COVID-19 pandemic: Two challenging and informative clinical cases

Background and Methods

There is an added level of complexity in the management of head and neck cancer patients with underlying immunosuppressive disorders during the COVID‐19 pandemic. Head and neck oncologists are tasked with balancing the dual risks of cancer progression in the setting of impaired tumor immunity and increased susceptibility to life‐threatening complications from exposure to viral infection for patients and providers. Through two cases of immunocompromised patients with newly diagnosed head and neck malignancies, we aim to provide guidance to clinicians struggling with how to best counsel and manage this unique subset of patients under these difficult circumstances.

Results

After careful consideration of the options, we took different approaches in the care of these two patients.

Conclusions

Ultimately, there is no uniform set of rules to apply to this heterogeneous group of immunocompromised patients. We provide some general principles to help guide patient management during the current pandemic.

Radiation-induced lymphopenia correlates with survival in nasopharyngeal carcinoma: impact of treatment modality and the baseline lymphocyte count

Background and purpose

We evaluated the relationship between patient-, tumor-, and treatment-related features and radiation-induced lymphopenia (RIL) and evaluated the correlation between RIL and survival outcome in NPC patients to help improve the treatment strategy.

Methods

This retrospective study included 374 patients with stage II-IVa NPC who had been treated with definitive RT and were enrolled from 2004 to 2015; The associations between the G3–4 RIL (absolute lymphocyte count, ALC <  0.5 × 10⁹ cells/L) during RT and patient-, tumor-, and treatment-related factors were assessed using Cox regression analyses. The correlation between ALC nadir and survival was examined using a Kaplan-Meier analysis, compared with the log-rank test, and confirmed by a Cox proportional hazards analysis.

Results

In the multivariate analysis, lower baseline ALC and intensity modulated radiation therapy (IMRT) (vs. 2 dimensional-conformal radiation therapy,2D-CRT) were identified as 2 independent factors that were associated with G3–4 RIL. In the multivariate survival analysis, patients with G3–4 ALC nadir had longer local recurrence-free survival durations (LRFS) (vs. G0–2 nadir, HR = 0.548, P = 0.005) and longer progression-free survival durations (PFS) (vs. G0–2 nadir, HR = 0.676, P = 0.022), while patients with G4 ALC nadir had a shorter distant-metastasis-free survival duration (DMFS) (vs. G0–2 nadir, hazard ratio [HR] = 2.567, P = 0.037).

Conclusions

In the study, lymphopenia during RT were affected by baseline ALC and RT modality independently. Moreover, G3–4 ALC nadir was independently linked with longer PFS and LRFS durations, while G4 ALC nadir was independently linked with a shorter DMFS duration.

A Phase 1 Trial Assessing the Safety and Tolerability of a Therapeutic DNA Vaccination Against HPV16 and HPV18 E6/E7 Oncogenes After Chemoradiation for Cervical Cancer

PURPOSE

This study assessed the safety and tolerability of therapeutic immunization against the human papillomavirus (HPV) viral oncoproteins E6 and E7 in patients with cervical cancer after chemoradiation.

METHODS AND MATERIALS

MEDI0457 (INO-3112) is a DNA-based vaccine targeting E6 and E7 of HPV-16/18 that is coinjected with an IL-12 plasmid followed by electroporation with the CELLECTRA 5P device. At 2 to 4 weeks after chemoradiation, patients with newly diagnosed stage IB1-IVA (cohort 1) or persistent/recurrent (cohort 2) cervical cancers were treated with 4 immunizations of MEDI0457 every 4 weeks. The primary endpoints were incidence of adverse events and injection site reactions. Immune responses against HPV antigens were measured by ELISpot for interferon-γ (IFNγ), enzyme-linked immunosorbent assay for antibody responses and multiplexed immunofluorescence for immune cells in cervical biopsy specimens.

RESULTS

Ten patients (cohort 1, n = 7; cohort 2, n = 3) with HPV16 (n = 7) or HPV18 (n = 3) cervical cancers received MEDI0457 after chemoradiation. Treatment-related adverse events were all grade 1, primarily related to the injection site. Eight of 10 patients had detectable cellular or humoral immune responses against HPV antigens after chemoradiation and vaccination: 6 of 10 patients generated anti-HPV antibody responses and 6 of 10 patients generated IFNγ-producing T cell responses. At the completion of chemoradiation and vaccination, cervical biopsy specimens had detectable CD8⁺ T cells and decreased PD-1⁺CD8⁺, PD-L1⁺CD8⁺, and PD-L1⁺CD68⁺ subpopulations. All patients cleared detectable HPV DNA in cervical biopsies by completion of chemoradiation and vaccination.

CONCLUSIONS

Adjuvant MEDI0457 is safe and well tolerated after chemoradiation for locally advanced or recurrent cervical cancers, supporting further investigation into combining tumor-specific vaccines with radiation therapy.

Palliative radiotherapy in advanced cancer patients treated with immune-checkpoint inhibitors: The PRACTICE study

In the present study, the influence of purely palliative radiotherapy (pRT) on the outcomes of patients with advanced cancer undergoing immune checkpoint blockade was evaluated. Patients were stratified into three groups: Patients who had received pRT within 6 months prior to the initiation of immunotherapy (previous pRT); patients who received pRT during immunotherapy (concurrent pRT); and patients who did not receive RT prior to or during immunotherapy (no RT group), and these groups were compared. The median overall survival (mOS), median progression free survival (mPFS) and median time-to-treatment failure (mTTF) for the previous pRT group were significantly shorter compared with the no RT group (mOS, 3.6 vs. 12.1 months, respectively, P=0.0095; mPFS 1.8 vs. 5.4 months, respectively, P=0.0016; mTTF 1.8 vs. 5.7 months, respectively, P=0.0035). The concurrent pRT group had a longer mTTF compared with the previous pRT group and similar outcomes to the no RT group. In the previous pRT group, 26.9% of the patients experienced immune-related adverse events compared with 40.1% of patients in the no RT group. Despite the use of pRT during immunotherapy being considered safe, the results of the present study suggest that pRT has a negative effect on immune balance.

Lymphocyte Count Kinetics, Factors Associated with the End-of-Radiation-Therapy Lymphocyte Count, and Risk of Infection in Patients with Solid Malignant Tumors Treated with Curative-Intent Radiation Therapy

PURPOSE

Lymphopenia has been associated with poor outcomes in patients with cancer. We sought to describe the lymphocyte kinetics in patients who received radiation therapy; to identify factors associated with the end-of-radiation-therapy (EoRT) lymphocyte count; and to determine the association of radiation therapy-induced lymphopenia with subsequent infection.

METHODS AND MATERIALS

Patients with solid malignant tumors treated at the Department of Oncology at Rigshospitalet, University of Copenhagen, Denmark, were included if they had received their first external beam radiation therapy with curative intent from January 2005 to December 2016 and had pretreatment and EoRT lymphocyte counts measured. Factors associated with the EoRT lymphocyte count were identified using regression analyses. The risk of subsequent infection was estimated using Cox proportional hazards regression.

RESULTS

We included 3920 patients. More patients had lymphopenia (<1000 cells/μL) at EoRT than at pretreatment (67.1% vs 14.9%; P < .001). Patients who received schemes with higher intensities (equivalent dose in 2-Gy fractions [EQD2] >65 Gy) in shorter time (<25 days) had a higher predicted EoRT lymphocyte count than patients who received schemes delivering EQD2 of 50 to 65 Gy in 25 to 45 days (1439 cells/μL, 95% confidence interval [1293-1585] vs 784 [754-814]). Radiation to multiple sites and concomitant chemotherapy use, particularly platinum compounds versus none, were associated with a lower EoRT lymphocyte count (698 [655-742] vs 852 [833-870]; and 612 [565-659] vs 937 [909-964], respectively). Patients with EoRT lymphopenia grade ≥3 (<500 cells/μL) had a higher risk of infection in the 3 months after radiation therapy (hazard ratio, 2.15 [95% confidence interval, 1.53-3.02]; P < .001), compared with patients with an EoRT lymphocyte count >1000 cells/μL.

CONCLUSIONS

The lymphocyte count declined during radiation therapy. Short duration schemes (<25 days), despite high total radiation dose (EQD2 >65 Gy), were associated with a higher EoRT lymphocyte count, whereas radiation to multiple sites and concomitant chemotherapy were associated with a lower count. EoRT lymphopenia was associated with an increased risk of infection.

Radiation-related Lymphopenia after Pelvic Nodal Irradiation for Prostate Cancer

Purpose

Given the uncertainty with regard to the effectiveness of pelvic nodal irradiation (PNI) for prostate cancer, we aimed to determine whether patients with prostate cancer who are treated with PNI are at a higher risk of developing radiation-related lymphopenia (RRL).

Methods and materials

The electronic charts of 886 consecutive patients treated with radiation therapy for prostate cancer between 2006 and 2018 at our institution were retrospectively analyzed. Qualifying patients were those with total lymphocyte counts within 1 year before and 3 to 24 months after the start of radiation therapy. Lymphopenia was the primary outcome, and overall survival and biochemical progression-free survival were secondary outcomes.

Results

Thirty-six patients with and 95 patients without PNI qualified for inclusion. In the PNI cohort, 61.1% of patients developed RRL (median follow-up total lymphocyte count < 1000 cells/μL) versus 26.3% of non-PNI patients (P < .001). On univariate analysis, initial prostate-specific antigen level, baseline lymphopenia, treatment modality, PNI status, increased planned target volume, and androgen deprivation therapy administration were all significant predictors of RRL (P < .05). On multivariate analysis, PNI status was a significant predictor of RRL (hazard ratio [HR], 3.42; 95% confidence interval [CI], 1.22-9.61; P < .001), as were initial prostate-specific antigen values (HR, 1.05; 95% CI, 1.00-1.11; P = .006) and baseline lymphopenia (HR, 8.32; 95% CI, 2.19-31.6; P = .007). RRL was not predictive for biochemical progression-free survival, distant metastasis, or overall survival on multivariate analysis, but the number of events was likely insufficient for these analyses.

Conclusions

The higher risk of RRL among patients with PNI comports with other papers that show that increased treatment volumes are associated with higher rates of RRL. Mounting evidence for the adverse effects of RRL on clinical outcomes supports the significance of our findings and suggests that further studies are needed on RRL as a potential harm of PNI that may affect the interpretation of results from clinical trials of PNI.

Post-operative radiation effects on lymphopenia, neutrophil to lymphocyte ratio, and clinical outcomes in palatine tonsil cancers

OBJECTIVE

To evaluate radiation-induced lymphopenia associated with unilateral vs. bilateral neck radiation and to test post-treatment neutrophil to lymphocyte ratio (NLR) as a prognostic clinical biomarker.

METHODS

This was a single academic center retrospective review of palatine tonsil squamous cell cancer patients treated with post-operative intensity modulated radiation therapy (IMRT) from 1997 to 2013. Absolute lymphocyte count (ALC) and NLR were evaluated during and after radiation for up to a year. Correlations of lab values with loco-regional control (LRC), freedom from distant metastases (FFDM), and overall survival (OS) were assessed.

RESULTS

Ninety-nine patients with median follow up 5.8 years had ALC recorded at least at baseline and within one year of starting RT. Acute grade 3-4 lymphopenia (<10 weeks from RT start) occurred in 79% of bilateral neck RT patients (n = 70) and 58% of unilateral neck RT patients (n = 29), p = 0.03. There was no significant difference in late grade 3-4 (p = 0.12) lymphopenia. In a multivariable Cox regression model, acute NLR > 11.875 correlated with worse OS (HR = 4.4, 95% CI 1.2-16). Late NLR > 6.875 independently correlated with significantly worse FFDM (HR = 16, 95% CI 1.9-137) and OS (HR = 12, 95% CI 3.0-48).

CONCLUSIONS

Unilateral neck radiation may prevent acute iatrogenic immunosuppression. In exploratory analyses, elevated post-treatment NLR was associated with risk for distant metastases and death.

Incidence of radiographically occult nodal metastases in HPV+ oropharyngeal carcinoma: Implications for reducing elective nodal coverage

PURPOSE

Initial deescalation studies for human papilloma virus (HPV)-positive driven oropharyngeal squamous cell carcinomas (HPV+ OPSCC) altered radiation therapy dose or the systemic agent used. Newer trials examine the disease control achieved with a reduced elective nodal field. We examined patterns of nodal involvement in patients with HPV+ OPSCC with a focus on implications for radiation field design for treatment deescalation.

METHODS AND MATERIALS

Records of patients with HPV+ OPSCC with preoperative imaging (computed tomography or fludeoxyglucose positron emission tomography/computed tomography) who underwent neck dissection without neoadjuvant therapy from 2010 to 2017 were retrospectively reviewed. The number and location of clinically positive lymph nodes on preoperative imaging were compared with those documented on pathology. These data were then used to establish the probability of missing nodal disease in 3 modified radiation field designs.

RESULTS

One hundred patients were included. The median time between imaging and surgery was 22 days. The most common clinical N stage was cN2a (35%), whereas the most common pathologic N stage was pN2b (45%). The median number of radiographically and pathologically involved nodes was 1 (range, 0-6) and 2 (range, 0-11), respectively. Forty-three percent of patients had more pathologically involved nodes than predicted on imaging, whereas 21% had pathologic involvement at an additional nodal level not predicted on imaging. Of the 21 patients with additional pathologically involved nodal levels, 14 had involvement of a directly adjacent station, 4 were patients with a cN0 hemineck with pathologically positive level II disease, and 3 had pathologic involvement of level 2 echelons removed from that predicted on imaging.

CONCLUSION

Our study suggests that radiation fields encompassing only clinically involved nodes or levels has an unacceptably high likelihood of missing subclinical disease. Alternatively, treating the first uninvolved echelon nodes in addition would cover pathologic sites of disease in 97% of patients. This approach merits further study in prospective trials.

Effect of surgery and radiotherapy on complete blood count, lymphocyte subsets and inflammatory response in patients with advanced oral cancer

Background

The immune system has a known role in the aetiology, progression and final treatment outcome of oral squamous cell cancers. The aim of this study was to evaluate the influence of radical surgery and radiotherapy on advanced oral squamous cell carcinoma blood counts, lymphocyte subsets and levels of acute inflammatory response markers.

Methods

Blood samples were obtained from 56 patients 5 days before and 10 days after surgery, 30 days and 1 year after radiotherapy. The whole blood count, lymphocyte subsets and inflammatory response markers (C-reactive protein, erythrocyte sedimentation rate, leukocyte count, expression of index CD64 and index CD163 on neutrophils and monocytes) were measured, statistically analysed and correlated with clinical treatment outcomes.

Results

The post-operative period was characterised by the onset of anaemia, thrombocytosis, lymphopenia with reduced B lymphocyte, T helper cell and NK cell counts, and a rise in acute phase reactants. Immediately after radiotherapy, the anaemia improved, the lymphopenia worsened, and thrombocyte levels returned to pre-treatment values. There was a drop in counts across the T and B cell lines, including a reduction in B lymphocytes, naïve and memory T cells with reduced CD4+ and CD8+ counts and a decreased CD4/CD8 ratio. One year after radiotherapy all the lymphocyte subsets remained depressed, the only exception being NK cells, whose levels returned to pre-treatment values.

Conclusions

We concluded that surgery resulted in a stronger acute phase response than radiotherapy, while radiotherapy caused a long-lasting reduction in lymphocyte counts. There was no correlation between any of the pre-treatment parameters and the clinical outcome.

Chemoradiotherapy-induced upregulation of PD-1 antagonizes immunity to HPV-related oropharyngeal cancer

While viral antigens in human papillomavirus (HPV)-related oropharyngeal cancer (HPVOPC) are attractive targets for immunotherapy, the effects of existing standard-of-care therapies on immune responses to HPV are poorly understood. We serially sampled blood from patients with stage III-IV oropharyngeal cancer undergoing concomitant chemoradiotherapy with or without induction chemotherapy. Circulating immunocytes including CD4(+) and CD8(+) T cells, regulatory T cells (Treg), and myeloid-derived suppressor cells (MDSC) were profiled by flow cytometry. Antigen-specific T-cell responses were measured in response to HPV16 E6 and E7 peptide pools. The role of PD-1 signaling in treatment-related immunosuppression was functionally defined by performing HPV-specific T-cell assays in the presence of blocking antibody. While HPV-specific T-cell responses were present in 13 of 18 patients before treatment, 10 of 13 patients lost these responses within 3 months after chemoradiotherapy. Chemoradiotherapy decreased circulating T cells and markedly elevated MDSCs. PD-1 expression on CD4(+) T cells increased by nearly 2.5-fold after chemoradiotherapy, and ex vivo culture with PD-1-blocking antibody enhanced HPV-specific T-cell responses in 8 of 18 samples tested. Chemoradiotherapy suppresses circulating immune responses in patients with HPVOPC by unfavorably altering effector:suppressor immunocyte ratios and upregulating PD-1 expression on CD4(+) T cells. These data strongly support testing of PD-1-blocking agents in combination with standard-of-care chemoradiotherapy for HPVOPC.

Association between severe treatment-related lymphopenia and progression-free survival in patients with newly diagnosed squamous cell head and neck cancer

BACKGROUND

Severe treatment-related lymphopenia occurs commonly in many cancers and is associated with early tumor progression. Data are lacking as to whether this occurs in squamous cell head and neck cancer.

METHODS

Serial total lymphocyte counts were retrospectively reviewed in patients with newly diagnosed squamous head and neck cancer undergoing chemoradiation and associated with treatment outcomes.

RESULTS

The median baseline total lymphocyte count in 56 patients was 1660 cells/mm(3) , which fell by 73% to 445 cells/mm(3) 2 months after initiating chemoradiation (p < .0001). Human papillomavirus negative (HPV-) patients with a total lymphocyte count <500 cells/mm(3) at 2 months had significantly earlier disease progression than those with higher total lymphocyte counts (hazard ratio [HR], 5.75; p = .045).

CONCLUSION

Baseline total lymphocyte counts were normal, but at 2 months approximately 60% of patients had severe treatment-related lymphopenia regardless of HPV status. Severe treatment-related lymphopenia in HPV- patients is independently associated with earlier disease progression. Prospective studies are needed to confirm these findings, which suggest that immune preservation is important in this cancer.

Efficacy of Varunadi Ghritha (polyherbal compound) in treated head and neck cancer cases as a biological response modifier

BACKGROUND

Persistent immune suppression is reported in Head and Neck Cancers (HNC) even after treatment and a higher recurrence rate was observed in patients with poor CD3 count. Loco regional recurrences and second primary tumours are the common forms of failure in head and neck cancers. Several agents have been tried to overcome this problem without much benefit. In Ayurveda, several plant based products have been reported to have anti-tumour and immunomodulatory properties.

AIM

To test the role of Varunadi Ghritha, as an immunomodulator in apparently healthy, treated and controlled HNC patients and to evaluate its effectiveness in preventing locoregional relapses and development of second primary tumours.

MATERIALS AND METHODS

Total 78 patients of treated head and neck cancers were randomly selected for intervention and control group. Patients in the intervention group (n = 38) received Varunadi Ghritha, 5gms twice daily for one year and followed up to two years. Patients in the control group (n = 40) were followed up at regular intervals. Immune parameters were assessed in the peripheral blood at base line and at the end of administration of the study compound.

RESULTS

In the intervention group, mean percentage increase in CD3, CD19 and CD16 positive cells were significantly higher after the administration of the study compound compared to the control group indicating an immunomodulatory effect of the study compound. A non-significant improvement in disease control was observed in patients with advanced stage of disease in the intervention group.

CONCLUSION

Administration of Varunadi Ghritha resulted in an increase in T cell counts in patients with treated HNC.

[Radiotherapeutical chromosomal aberrations in laryngeal cancer patients]

INTRODUCTION

The authors present the results of cytogenetic analysis of 21 patients with laryngeal carcinomas diagnosed and treated in the period 1995-2000 at the Institute of Otorhinolaryngology and Maxillofacial Surgery, Clinical Center of Serbia and Clinical Center of Novi Sad.

MATERIAL AND METHODS

The patients were specially monitored and the material was analyzed at the Institute of Human Genetics of the School of Medicine in Belgrade as well as in the Laboratory for Radiological Protection of the Institute of Occupational and Radiological Health "Dr Dragomir Karajovic" in Belgrade.

RESULTS

The incidence of chromosomal aberrations and incidence of exchange of material between sister chromatids were observed in the preparation of the metaphasic lymphocyte chromosomes of the peripheral blood obtained in the culture. Structural aberrations were found on the chromosomes in the form of breakups, rings, translocations and dicentrics as early as after a single exposure of patients to tumor radiation dose of 2 Gy in the field sized 5x7. Out of the total number of 35 cultivated blood samples obtained from 13 patients, 21 were successfully cultivated and they were proved to contain chromosomal aberrations. Some of the peripheral blood samples failed to show cell growth in vitro due to the lethal cell damages in vivo.

DISCUSSION

We have concluded that the number of structural aberrations cannot be used as a biological measure of the absorbed ionizing radiation dose. The presence of aberrations per se is indicative of the mutagenic effect of the ionizing radiation, which was also confirmed in our series on the original model by cultivation of the peripheral blood lymphocytes in the culture of the cells of the volunteer donors upon in vitro radiation. Using the method of bromdeoxyuridylreductase, the increased incidence of SCE as a mutagenic effect was registered.

CONCLUSION

It has been concluded that the increase of absorbed radiation dose in vitro leads to prolonged duration of cell cycle in the same conditions, which proves cytostatic effect of radiation. Further fundamental studies are required for clinical implementation of the findings.

Significant impairment in immune recovery after cancer treatment

BACKGROUND

Although immunosuppression from cancer adjuvant therapy has been documented, how these suppressed immune responses recover to baseline values after completion of cancer adjuvant therapy has not been studied systematically.

OBJECTIVES

The objective of this study was to examine the probability of immune recovery after cancer adjuvant therapy and the potential impact of cancer adjuvant therapy type and cancer stage on immune recovery in patients with newly diagnosed breast cancer.

METHODS

In a repeated-measures design, immune responses were measured four times in 80 patients with early-stage breast cancer: before and at 2, 6, and 12 months from the beginning of cancer adjuvant therapy. Natural killer cell activity, lymphokine-activated killer cell activity, lymphocyte proliferation, CD subsets (CD4, CD8, and CD56), and cytokines (interferon-gamma, interleukin [IL]-2, IL-4, IL-6, and IL-1alpha) were selected for their relevance to breast cancer. Immune recovery was defined by the level of immune response reaching to and above baseline levels. Data were analyzed using a multivariate generalized linear mixed-model approach.

RESULTS

Delayed immune recovery to pretreatment baseline levels continued to the 12-month time point in all parameters. The percentages of immune recovery ranged from 6% to 76% of the patients, varying among immune parameters. Overall, immune recovery was poorer for interferon-gamma, IL-2, IL-4, lymphocyte proliferation, and natural killer cell activity than was for CD subsets and IL-6. The type of cancer adjuvant therapy, not cancer stage, showed selective influence on immune recovery. Chemotherapy or chemotherapy and radiotherapy combination significantly delayed IL-2 recovery, whereas radiotherapy significantly delayed IL-4 recovery.

DISCUSSION

Immune recovery after breast cancer adjuvant therapy is delayed significantly for an extended time period in numerous immune parameters. The type of cancer adjuvant therapy has selective influence on immune recovery. Future investigations are warranted to elucidate the time course of immune recovery, clinical significance of poor immune recovery, and factors influencing immune recovery to develop potential interventions.

Primary CNS lymphoma as second malignancy in a case of carcinoma larynx treated with chemoradiation

A 66-year-old male was diagnosed as carcinoma larynx in the year April 2004. He was treated with concurrent chemoradiation and remained disease free for three consecutive years. After 3 years he suddenly complained of giddiness and seizures. Magnetic Resonance Imaging of brain showed features of primary CNS lymphoma (PCNSL) which was confirmed by histopathology test. To the best of our knowledge PCNSL as second malignancy in a case of carcinoma of head and neck has not been reported till date. The PCNSL in this patient may have resulted from depressed immunity due to previous radiotherapy. Whatever may be the predisposing cause, this case is most probably the first reported case of PCNSL in a patient of squamous cell carcinoma of larynx.

Differential responses of cellular immunity in patients undergoing neoadjuvant therapy followed by surgery for carcinoma of the oesophagus

BACKGROUND

To compare immune responses following neoadjuvant chemoradiation therapy in combination with hyperthermia plus surgery to those induced by surgery alone in patients with oesophageal cancer.

METHODS

Thirty-two patients with histopathologically proven oesophageal cancer, scheduled for potentially curative transhiatal or transthoracic oesophagectomy with (neo, n = 20) or without (control, n = 12) neoadjuvant thermochemoradiation therapy (ThCR) were included. Peripheral blood samples were obtained before ThCR, after 2 weeks of ThCR, 1 day before surgery, on postoperative days 1, 3, 7, and 6 weeks after surgery, for white blood cell counts, lymphocyte subsets and T helper type 1 (Th1) and type 2 (Th2) lymphocyte responses.

RESULTS

Neo patients showed a significant decrease in granulocytes and lymphocyte subsets, and T cell cytokines after 2 weeks of ThCR. Only CD8+ (cytotoxic) T cells recovered after ThCR to reach normal levels prior to surgery. In contrast, CD4+ T (helper) cells, and NK- and B cells in neo patients did not recover prior to surgery (all P < 0.05). Oesophagectomy induced a significant increase in granulocytes and a decrease in lymphocytes (and subsets). Only those subsets that had not recovered after ThCR (CD4+ T cells, NK and B cells but not CD8+ T cells), were significantly lower (all P < 0.05) during the entire postoperative study period. Postoperatively, the stimulated cytokine production capacity of Th1 and Th2 cells, corrected for number of T cells, was not significantly different between the groups.

CONCLUSION

Neoadjuvant thermochemoradiation for oesophageal cancer caused significant disturbances of host cellular immunity with reduced T, NK and B cell counts, and differential recovery of cytotoxic and helper T cells leading to prolonged T cell imbalance that extends beyond the time of surgery. The functional and anti-tumour consequences of this immunodisturbance need further investigation, as recovery of T helper cytokine production towards surgery was less impaired than T helper cell counts.

Combining a recombinant cancer vaccine with standard definitive radiotherapy in patients with localized prostate cancer

PURPOSE

Many patients with clinically localized prostate cancer develop biochemical failure despite excellent local therapy perhaps due to occult metastatic disease. One potential solution is the utilization of a well-tolerated systemic therapy (e.g., vaccine) in concert with local therapy.

EXPERIMENTAL DESIGN

We present a randomized phase II clinical trial designed to determine if a poxviral vaccine encoding prostate-specific antigen (PSA) can induce a PSA-specific T-cell response when combined with radiotherapy in patients with clinically localized prostate cancer. Thirty patients were randomized in a 2:1 ratio into vaccine plus radiotherapy or radiotherapy-only arms. Those patients in the combination arm received a "priming" vaccine with recombinant vaccinia (rV) PSA plus r V containing the T-cell costimulatory molecule B7.1 (rV-B7.1) followed by monthly booster vaccines with recombinant fowlpox PSA. The vaccines were given with local granulocyte-macrophage colony-stimulating factor and low-dose systemic interleukin-2. Standard external beam radiation therapy was given between the fourth and the sixth vaccinations.

RESULTS

Seventeen of 19 patients in the combination arm completed all eight vaccinations and 13 of these 17 patients had increases in PSA-specific T cells of at least 3-fold versus no detectable increases in the radiotherapy-only arm (P < 0.0005). There was also evidence of de novo generation of T cells to well-described prostate-associated antigens not found in the vaccine, providing indirect evidence of immune-mediated tumor killing. The vaccine was well tolerated.

CONCLUSION

This vaccine regimen can be safely given in patients undergoing radiation therapy for localized prostate cancer, with the majority of patients generating a PSA-specific cellular immune response to vaccine.

DNA fusion gene vaccines against cancer: from the laboratory to the clinic

Vaccination against target antigens expressed by cancer cells has now become a realistic goal. DNA vaccines provide a direct link between identification of genetic markers in tumors and vaccine formulation. Simplicity of manufacture facilitates construction of vaccines against disease subsets or even for individual patients. To engage an immune system that exists to fight pathogens, we have developed fusion gene vaccines encoding tumor antigens fused to pathogen-derived sequences. This strategy activates high levels of T-cell help, the key to induction and maintenance of effective immunity. We have dissected the immunogenic tetanus toxin to obtain specific sequences able to activate antibody, CD4+, or CD8+ T cells to attack selected fused tumor antigens. Principles established in preclinical models are now being tested in patients. So far, objective immune responses against idiotypic antigen of neoplastic B cells have been observed in patients with B-cell malignancies and in normal transplant donors. These responses provide a platform for testing physical methods to improve DNA delivery and strategies to boost responses. For cancer, demands are high, because vaccines have to activate powerful immunity against weak antigens, often in a setting of immune damage or tolerance. Vaccination strategies against cancer and against microbes are sharing knowledge and technology for mutual benefit.

Phase II trial of gemcitabine concurrent with radiation for locally advanced squamous cell carcinoma of the head and neck

BACKGROUND

Concurrent chemoradiation is the current standard of treatment for patients with advanced unresectable head and neck squamous cell carcinoma (HNSCC). Due to the potent radiosensitizing properties of gemcitabine, we decided to assess its efficacy and toxicity with concurrent radiation in patients with advanced HNSCC.

PATIENTS AND METHODS

From January 1997 to December 2001, 27 patients with locally advanced HNSCC (stage III, 37%; stage IV, 63%) were enrolled. All received a course of radiotherapy (70 Gy over 7 weeks) concurrent with weekly infusions of gemcitabine at 100 mg/m2 or 50 mg/m2.

RESULTS

All patients were assessable for toxicity and 26 for response. Severe mucositis (grade 3-4) was observed in 74% of patients (grade 4, 41%). Severe hematological toxicity was uncommon. Mild and moderate xerostomy was the most common late toxicity in 23 patients (85%). The median radiation dose delivered was 70 Gy (40-80 Gy), 25 patients (93%) received > or = 80% of the intended dose. Gemcitabine dose intensity was > or = 80% in only 13 (48%) patients. The rate of complete and partial responses were 61% and 27%, respectively, for an overall response rate of 88%. At a median follow-up of 13 months (range 6-62), the actuarial 3-year progression-free survival (PFS) and overall survival (OS) were 37% and 33%, respectively. The only variable associated with prolonged survival (P = 0.0001) was the degree of response. No difference was observed in response or toxicity with either gemcitabine 50 or 100 mg/m2.

CONCLUSIONS

The concurrent use of radiotherapy and gemcitabine is effective but produces manageable severe mucositis in a high percentage of patients.