Stereotactic body radiotherapy plus cetuximab for previously irradiated un-resectable head and neck cancer

Evidence-based clinical recommendations for hypofractionated radiotherapy: exploring efficacy and safety - Part 1. Brain and head and neck

Advances in radiotherapy (RT) techniques, including intensity-modulated RT and image-guided RT, have allowed hypofractionation, increasing the fraction size over the conventional dose of 1.8-2.0 Gy. Hypofractionation offers advantages such as shorter treatment times, improved compliance, and under specific conditions, particularly in tumors with a low α/β ratio, higher efficacy. It was initially explored for use in RT for prostate cancer and adjuvant RT for breast cancer, and its application has been extended to various other malignancies. Hypofractionated RT (HFRT) may also be effective in patients who are unable to undergo conventional treatment owing to poor performance status, comorbidities, or old age. The treatment of brain tumors with HFRT is relatively common because brain stereotactic radiosurgery has been performed for over two decades. However, re-irradiation of recurrent lesions and treatment of elderly or frail patients are areas under investigation. HFRT for head and neck cancer has not been widely used because of concerns regarding late toxicity. Thus, we aimed to provide a comprehensive summary of the current evidence for HFRT for brain tumors and head and neck cancer and to offer practical recommendations to clinicians faced with the challenge of choosing new treatment options.

Reirradiation of head and neck squamous cell carcinomas: a pragmatic approach-part I: prognostic factors and indications to treatment

INTRODUCTION

Reirradiation (reRT) of locally recurrent/second primary tumors of the head and neck region is a potentially curative treatment for patients not candidate to salvage surgery. Aim of the present study is to summarize available literature on both prognostic factors and indications to curative reRT in this clinical setting.

MATERIALS AND METHODS

A narrative review of the literature was performed on two topics: (1) patients' selection according to prognostic factors and (2) dosimetric feasibility of reRT. Postoperative reRT and palliative intent treatments were out of the scope of this work.

RESULTS

Patient-tumor and treatment-related prognostic factors were analyzed, together with dosimetric parameters concerning target volume and organs at risk. Based on available evidence, a stepwise approach has been proposed aiming to provide a useful tool to identify suitable candidates for curative reRT in clinical practice. This was then applied to two clinical cases, proposed at the end of this work.

CONCLUSION

A second course of RT in head and neck recurrence/second primary tumors is a personalized approach that can be offered to selected patients only in centers with expertise and dedicated equipment following a multidisciplinary team discussion.

Advancements of radiotherapy for recurrent head and neck cancer in modern era

Head and neck cancer is a kind of cancer which can be eradicated from radical radiation therapy. However, with best efforts, nearly 40% patients will experience locoregional recurrence. Locoregional recurrence is the main cause of cancer-related death in head and neck cancers, so local treatments play a key role in improving progression free survival. In the last decades, radiation techniques have been tremendously developed, highly conformal radiation techniques such as intensity-modulated radiotherapy, stereotactic body radiation therapy, brachytherapy and proton or heavy ion radiation therapy have their unique radiobiological advances. Although reirradiation is widely used in clinical practice, but little is known when comparing the different techniques. In this review, we will provide a comprehensive overview of the role of reirradiation in recurrent head and neck cancers including radiation techniques, patient selection, overall clinical benefits, and toxicities.

The immunogenic radiation and new players in immunotherapy and targeted therapy for head and neck cancer

Although treatment modalities for head and neck cancer have evolved considerably over the past decades, survival rates have plateaued. The treatment options remained limited to definitive surgery, surgery followed by fractionated radiotherapy with optional chemotherapy, and a definitive combination of fractionated radiotherapy and chemotherapy. Lately, immunotherapy has been introduced as the fourth modality of treatment, mainly administered as a single checkpoint inhibitor for recurrent or metastatic disease. While other regimens and combinations of immunotherapy and targeted therapy are being tested in clinical trials, adapting the appropriate regimens to patients and predicting their outcomes have yet to reach the clinical setting. Radiotherapy is mainly regarded as a means to target cancer cells while minimizing the unwanted peripheral effect. Radiotherapy regimens and fractionation are designed to serve this purpose, while the systemic effect of radiation on the immune response is rarely considered a factor while designing treatment. To bridge this gap, this review will highlight the effect of radiotherapy on the tumor microenvironment locally, and the immune response systemically. We will review the methodology to identify potential targets for therapy in the tumor microenvironment and the scientific basis for combining targeted therapy and radiotherapy. We will describe a current experience in preclinical models to test these combinations and propose how challenges in this realm may be faced. We will review new players in targeted therapy and their utilization to drive immunogenic response against head and neck cancer. We will outline the factors contributing to head and neck cancer heterogeneity and their effect on the response to radiotherapy. We will review in-silico methods to decipher intertumoral and intratumoral heterogeneity and how these algorithms can predict treatment outcomes. We propose that (a) the sequence of surgery, radiotherapy, chemotherapy, and targeted therapy should be designed not only to annul cancer directly, but to prime the immune response. (b) Fractionation of radiotherapy and the extent of the irradiated field should facilitate systemic immunity to develop. (c) New players in targeted therapy should be evaluated in translational studies toward clinical trials. (d) Head and neck cancer treatment should be personalized according to patients and tumor-specific factors.

Reirradiation of head and neck squamous cell carcinomas: a pragmatic approach, part II: radiation technique and fractionations

INTRODUCTION

Reirradiation (reRT) of local recurrent/second primary tumors of the head and neck represents a potential curative treatment for patients not candidate to a salvage surgery. Aim of the present study is to summarize literature data on modern radiation techniques and fractionations used in this setting of patients.

MATERIALS AND METHODS

A narrative review of the literature was conducted on three topics: (1) target volume delineation (2) reRT dose and techniques and (3) ongoing studies. Patients treated with postoperative reRT and palliative intent were not considered for the current analysis.

RESULTS

Recommendations on the target volume contouring have been reported. 3D-Conformal Radiotherapy, Intensity Modulated Radiotherapy, Stereotactic body Radiotherapy Intraoperative Radiotherapy, Brachytherapy and Charged Particles have been analyzed in terms of indication and fractionation in the field of reRT. Ongoing studies on the topic have been reported for IMRT and Charged Particles. Moreover, according to literature data a stepwise approach has been proposed aiming to provide a useful tool to select patients candidate to a curative reRT in daily clinical practice. Two clinical cases were also provided for its application.

CONCLUSION

Different radiation techniques and fractionations can be used for a second course of radiotherapy in patients with recurrent/second primary tumor of head and neck region. Tumor characteristics as well as radiobiological considerations should be take into account to define the best reRT approach.

Salvage Post-Operative Stereotatic Ablative Radiotherapy for Re-Current Squamous Cell Carcinoma of Head and Neck

Background and Objectives: Patients with recurrent squamous cell carcinoma of the head and neck (rHNC) face an aggressive disease. Surgical resection is the gold standard treatment. Immediate adjuvant post-operative stereotactic ablative radiotherapy (PO-SABR) for rHNC is debatable. Materials and Methods: We retrospectively identified patients who were treated with PO-SABR at the AC Camargo Cancer Center, Brazil. Results: Eleven patients were treated between 2018 and 2021. The median time between salvage surgery and PO-SABR was 31 days (range, 25–42) and the median PO-SABR total dose was 40 Gy (range, 30–48 Gy). The 2-and 4-year actuarial DFS were 62.3% and 41.6%, while the 2-and 4-year OS probabilities were 80.0% and 53.3%, respectively. Eight (72.7%) patients were alive and six (54.5%) were without disease at the last follow-up. Two (18.1%) patients had local failure in the PO-SABR field. Three (27.3%) patients had distant metastasis, diagnosed in a median time of 9 months (range, 4–13) after completion of PO-SABR. On univariate analysis, predictive factors related to worse OS were: interval between previous radiotherapy and PO-SABR ≤ 24 months (p = 0.033) and location of the salvage target in the oral cavity (p = 0.013). The total dose of PO-SABR given in more than three fractions was marginally statistically significant, favoring the OS (p = 0.051). Conclusions: Our results encourage the use of a more aggressive approach in selected patients with rHNC by combining salvage surgery with immediate PO-SABRT, but this association needs to be further explored.

The functional significance and cross-talk of non-coding RNAs in triple negative and quadruple negative breast cancer

One of the leading causes of cancer-related deaths worldwide is breast cancer, among which triple-negative breast cancer (TNBC) is the most malignant and lethal subtype. This cancer accounts for 10-20% of all breast cancer deaths. Proliferation, tumorigenesis, and prognosis of TNBC are affected when the androgen receptor (AR) is not expressed, and it is classified as quadruple negative breast cancer (QNBC). Non-coding RNAs, such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), play a significant role in tumorigenesis by virtue of their oncogenic and tumor-suppressive properties. To regulate tumorigenesis, miRNAs interact with their target mRNAs and modulate their expression, whereas lncRNAs can either act alone or interact with miRNAs or other molecules through various signaling pathways. Conversely, circRNAs regulate tumorigenesis by acting as miRNA sponges predominantly. Recently, non-coding RNAs were studied comprehensively for their roles in tumor proliferation, progression, and metastasis. As a result of existing studies and research progress, non-coding RNAs have been implicated in TNBC, necessitating their use as biomarkers for future diagnostic applications. In this review, the non-coding RNAs are explicitly implicated in the regulation of breast cancer, and their cross-talk between TNBC and QNBC is also discussed.