Is Locally Advanced Head-Neck Cancer One More Candidate for Accelerated Hypofractionation?

Neoplasia-related and treatment-induced lymphopenia: impact on the outcome of chemoradiotherapy in laryngeal cancer

INTRODUCTION

The role of the immune system in the efficacy of radiotherapy (RT) has been well established. We examined the role of neoplasia-related and treatment-induced lymphopenia in the outcome of RT or chemoradiotherapy (CRT) in squamous cell laryngeal cancer.

MATERIALS AND METHODS

We retrospectively analyzed a series of 135 laryngeal carcinomas treated with radical or postoperative RT/CRT. Six lymphocyte-related variables were defined and examined: i. lymphocyte counts (LCs) before a brief course of induction chemotherapy, ii. pre-RT LCs, iii. post-RT LCs, iv. pre-RT neutrophil/lymphocyte ratio (N/L), v. pre-RT monocyte/lymphocyte ratio (M/L), and vi. pre-RT platelet/lymphocyte ratio (Pt/L).

RESULTS

RT and CRT resulted in a significant decrease of LCs at the end of therapy, and this was significantly more prominent in patients treated with radical intent and neck irradiation (median LC nadir 810/μl vs. 1250/μl; p = .0003). Induction chemotherapy did not intensify the lymphotoxic effect of RT. LCs lower than the 33rd percentile before RT (<1718/μl) and after RT (<720/μl) were significantly linked to poor locoregional progression-free survival (LRFS; p = .02 and p = .08, respectively) and disease-specific overall survival (OS; p = .02 and p = .03, respectively). This was also confirmed multivariate analysis (LRFS: p = .006/HR = 2.41 and p = .08/HR = 1.76, respectively; OS: p = .001/HR = 3.06 and p = .02/HR = 2.07, respectively). High pre-RT N/L, M/L, and Pt/L ratios were also of ominous prognostic relevance.

CONCLUSIONS

Both neoplasia-related and RT-induced lymphopenia define the outcome of RT in terms of locoregional failure, incidence of metastasis, and, finally, disease-specific survival of patients with laryngeal cancer. Restoration of pre-RT lymphopenia and protection of peripheral lymphocytes during RT emerge as critical issues that demand therapeutic interventions to maximize the efficacy of RT/CRT in patients with laryngeal cancer.

Is anti-PD-1 immunotherapy a means for post-irradiation tumor clearance in head and neck cancer?

Chemo-radiotherapy is the standard treatment for locally advanced head-neck cancer (LA-HNC). However, about 30% of tumors do not respond or even progress shortly after the completion of radiotherapy. We investigated whether anti-PD1 immunotherapy can eradicate the irradiated tumor and reverse the ominous prognosis of these patients. We retrospectively analyzed a small series of 9 patients with LA-HNC who did not respond (6/9) or showed local disease progression (3/9) during chemo-radiotherapy and were treated with nivolumab anti-PD1 immunotherapy. Immunotherapy started 1.5 months after the end of radiotherapy. Out of 9 patients, 3 (33.3%) had a complete response and 3 (33.3%) partial response at 6 months after the onset of immunotherapy. Two patients are alive with no evidence of disease at 36 months. One more patient with partial response and without disease progression survived 16 months after therapy when he died from intercurrent disease. Immunotherapy showed an excellent tolerance profile. One patient developed an extensive skin rash on the 16th cycle. Anti-PD-1 immunotherapy after radiotherapy can lead to clearance of the remnant tumor and ameliorate the prognosis of patients. Randomized trials are necessary to establish post-irradiation immunotherapy as a standard of care in this ill-fated subgroup of HNC patients.

Precision medicine for risk prediction of oral complications of cancer therapy–The example of oral mucositis in patients receiving radiation therapy for cancers of the head and neck

Oral complications of cancer therapy are common, markedly symptomatic, negatively impact patients' quality of life, and add significantly to the cost of care. Patients' risk of treatment-related toxicities is not uniform; most patients suffer at least one side effect, while others tolerate treatment without any. Understanding those factors which impact risk provides opportunities to customize cancer treatment plans to optimize tumor kill and minimize regimen-related toxicities. Oral mucositis (OM) is an iconic example of a clinically significant and common complication of head and neck radiotherapy. Individuals' OM risk is governed by the cumulative impact of factors related to treatment, the tumor, and the patient. In addition to OM risk prediction, a second opportunity to apply precision medicine will evolve as viable treatment options become available. Patients vary widely in how well or poorly they respond to specific treatments. What works well in one individual, might fail in another. Prospective determination of the likelihood of a patient's response or non-response is based on a range of biological interactions. Coupled with risk determination, the application of precision medicine will allow caregivers, patients, and payers to integrate risk/benefit to optimize the probability that the best treatment is be given to the most appropriate patients.

Prognostic and Predictive Relevance of Tumor-Infiltrating Lymphocytes in Squamous Cell Head-Neck Cancer Patients Treated with Radical Radiotherapy/Chemo-Radiotherapy

Microenvironmental conditions control the entrance and thriving of cytotoxic lymphocytes in tumors, allowing or preventing immune-mediated cancer cell death. We investigated the role of tumor-infiltrating lymphocyte (TIL) density in the outcome of radiotherapy in a series of squamous cell head−neck tumors (HNSCC). Moreover, we assessed the link between markers of hypoxia and TIL density. One-hundred twenty-one patients with HNSCC treated prospectively with radical radiotherapy/chemo-radiotherapy were analyzed. The assessment of TIL density was performed on hematoxylin and eosin biopsy sections before radiotherapy. TIL density ranged from 0.8 to 150 lymphocytes per ×40 optical field (median 27.5). Using the median value, patients were grouped into two categories of low and high TIL density. Early T-stage tumors had a significantly higher TIL density (p < 0.003), but we found no association with N-stage. Overexpression of HIF1α, HIF2α, and CA9 was significantly linked with poor infiltration by TILs (p < 0.03). A significant association of high TIL density with better disease-specific overall survival and improved locoregional relapse-free survival was noted (p = 0.008 and 0.02, respectively), which was also confirmed in multivariate analysis. It is concluded that HNSCC phenotypes that allow for the intratumoral accumulation of lymphocytes have a better outcome following radical radiotherapy/chemo-radiotherapy. Intratumoral-activated HIF- and CA9-related pathways characterize immunologically cold tumors and may be used as targets for therapeutic interventions.