Concurrent adjuvant radiotherapy and interferon-α2b for resected high risk stage III melanoma – a retrospective single centre study

Interaction between Radiation Therapy and Targeted Therapies in HER2-Positive Breast Cancer: Literature Review, Levels of Evidence for Safety and Recommendations for Optimal Treatment Sequence

Purpose: Over the past twenty years, anti-HER2 targeted therapies have proven to be a revolution in the management of human epidermal growth receptor 2 (HER2)-positive breast cancers. Anti-HER2 therapies administered alone or in combination with chemotherapy have been specifically studied. Unfortunately, the safety of anti-HER2 therapies in combination with radiation remains largely unknown. Thus, we propose a literature review of the risks and safety of combining radiotherapy with anti-HER2 therapies. We will focus on the benefit/risk rationale and try to understand the risk of toxicity in early-stage and advanced breast cancer. Methods: Research was carried out on the following databases: PubMed, EMBASE, ClinicalTrial.gov, Medline, and Web of Science for the terms "radiotherapy", "radiation therapy", "radiosurgery", "local ablative therapy", and "stereotactic", combined with "trastuzumab", "pertuzumab", "trastuzumab emtansine", "TDM-1", "T-Dxd", "trastuzumab deruxtecan", "tucatinib", "lapatinib", "immune checkpoint inhibitors", "atezolizumab", "pembrolizumab", "nivolumab", "E75 vaccine", "interferon", "anti-IL-2", "anti-IL 12", and "ADC". Results: Association of radiation and monoclonal antibodies such as trastuzumab and pertuzumab (with limited data) seems to be safe, with no excess risk of toxicity. Preliminary data with radiation and of antibody-drug conjugate of trastuzumab combined cytotoxic (trastuzumab emtansine, trastuzumab deruxtecan), given the underlying mechanism of action, suggest that one must be particularly cautious with the association. The safety of the combination of a tyrosine kinase inhibitor (lapatinib, tucatinib) and radiation remains under-studied. The available evidence suggests that checkpoint inhibitors can be safely administrated with radiation. Conclusions: HER2-targeting monoclonal antibodies and checkpoint inhibitors can be combined with radiation, apparently with no excess toxicities. Caution is required when associating radiation with TKI and antibody drugs, considering the limited evidence.

Combining Radiation Therapy With Interferons: Back to the Future

Radiation therapy has been linked to the induction of an intratumoral type I interferon (IFN) response, which positively affects the response to treatment. This has spiked the interest to combine radiation therapy with IFN-based treatment. Interestingly, this combination treatment has been considered previously, since preclinical studies demonstrated a radiosensitizing effect of interferons. As a result, multiple clinical trials have been performed combining radiation therapy with interferons in different tumor types. Although potential benefit has been suggested, the outcomes of the trials are diverse and challenging to interpret. In addition, increased grade ≥3 toxicity frequently resulted in a negative recommendation regarding the combination therapy. The latter appears premature because many studies were small and several aspects of the combination treatment have not yet been sufficiently explored to justify such a definite conclusion. This review summarizes the available literature on this combination therapy, with a focus on IFN-α and IFN-β. Based on preclinical studies and clinical trials, we evaluated the potential opportunities and describe the current challenges. In addition, we identify several issues that should be addressed to fully exploit the potential benefit of this combinatorial treatment approach.

Ipilimumab may increase the severity of cutenaous toxicity related to radiotherapy

Ipilimumab, monoclonal antibody against cytotoxic T-lymphocyte antigen-4 and, radiotherapy are commonly used to treat unresectable and metastatic melanoma. As a result of upregulation of immune system with ipilimumab, many immune-related adverse effects, such as dermatitis, colitis, hepatitis, and hypophysitis, have been previously reported in literature. Typically, these effects are treated with high-dose steroids and mostly heal up. Here, we report a case who was receiving radiotherapy due to metastatic malignant melanoma with atypical generalized rash, which was enlarged with concurrent ipilimumab treatment.

Role for radiation therapy in melanoma

Although melanoma is generally considered a relative radioresistant tumor, radiation therapy (RT) remains a valid and effective treatment option in definitive, adjuvant, and palliative settings. Definitive RT is generally only used in inoperable patients. Despite a high-quality clinical trial showing adjuvant RT following lymphadenectomy in node-positive melanoma patients prevents local and regional recurrence, the role of adjuvant RT in the treatment of melanoma remains controversial and is underused. RT is highly effective in providing symptom palliation for metastatic melanoma. RT combined with new systemic options, such as immunotherapy, holds promise and is being actively evaluated.

The role of radiation therapy in melanoma

Although melanoma was historically thought to be radiation resistant, there are limited data to support the use of adjuvant radiation therapy for certain situations at increased risk for locoregional recurrence. High-risk primary tumor features include thickness, ulceration, certain anatomic locations, satellitosis, desmoplastic/neurotropic features, and head and neck mucosal and anorectal melanoma. Lentigo maligna can be effectively treated with either adjuvant or definitive radiation therapy. Some retrospective and prospective randomized studies support the use of adjuvant radiation to improve regional control after lymph node dissection for high-risk nodal metastatic disease. Consensus on the optimal radiation doses and fractionation is lacking.

Combinations of radiation therapy and immunotherapy for melanoma: a review of clinical outcomes

Radiation therapy has long played a role in the management of melanoma. Recent advances have also demonstrated the efficacy of immunotherapy in the treatment of melanoma. Preclinical data suggest a biologic interaction between radiation therapy and immunotherapy. Several clinical studies corroborate these findings. This review will summarize the outcomes of studies reporting on patients with melanoma treated with a combination of radiation therapy and immunotherapy. Vaccine therapies often use irradiated melanoma cells, and may be enhanced by radiation therapy. The cytokines interferon-α and interleukin-2 have been combined with radiation therapy in several small studies, with some evidence suggesting increased toxicity and/or efficacy. Ipilimumab, a monoclonal antibody which blocks cytotoxic T-lymphocyte antigen-4, has been combined with radiation therapy in several notable case studies and series. Finally, pilot studies of adoptive cell transfer have suggested that radiation therapy may improve the efficacy of treatment. The review will demonstrate that the combination of radiation therapy and immunotherapy has been reported in several notable case studies, series and clinical trials. These clinical results suggest interaction and the need for further study.

Concurrent radiotherapy and ipilimumab immunotherapy for patients with melanoma

Ipilimumab and radiotherapy are commonly used to treat unresectable and metastatic melanoma. Results from preclinical studies and case reports suggest a biologic interaction between these two treatments. To understand the clinical implications of the interaction, we carried out a retrospective study reviewing records of patients treated with ipilimumab and radiotherapy for melanoma at our institution between 2005 and 2011. The review included details of treatment, response, adverse events (AE), and overall survival (OS). Twenty-nine patients underwent 33 courses of non-brain radiotherapy between their first and last dose of ipilimumab. Immune-related AEs (ir-AEs) were observed in 43% of patients receiving ipilimumab at 10 mg/kg and in 22% of patients receiving 3 mg/kg; the frequency of ir-AEs was not significantly different compared with previous studies of ipilimumab alone. Radiotherapy-related AEs were significantly more common in patients receiving higher doses of radiation. Palliation of symptoms was reported by 77% of patients after radiotherapy. Median OS was 9 and 39 months in patients receiving radiotherapy during induction and maintenance with ipilimumab, respectively. In this retrospective study, concurrent ipilimumab and radiotherapy was neither associated with higher than expected rates of AEs nor did it abrogate palliative effects of radiotherapy or survival benefits of ipilimumab. Further studies to prospectively explore the efficacy of this therapeutic combination are warranted.

An update on pegylated IFN-α2b for the adjuvant treatment of melanoma

For patients with localized melanoma, excision of the primary tumor, including lymphadenectomy for nodal metastases, is standard treatment. However, patients with large primary tumors (stage IIB and IIC) or stage III melanoma have a relatively poor prognosis owing to the high risk of recurrence. High-dose IFN-α2b and pegylated IFN-α2b (PEG-IFN-α2b) are the only approved options for adjuvant therapy of stage III melanoma, but the lack of comparative data has led to considerable confusion in choosing between these options. In this article, current evidence regarding the pharmacokinetics, efficacy, safety and tolerability of adjuvant PEG-IFN-α2b in patients with melanoma is reviewed, with frequent reference to and comparisons with data using IFN-α2b. Particular focus is given to the pharmacokinetic differences between IFN-α2b and PEG-IFN-α2b and their implications for the treatment of high-risk patients. In addition, emerging evidence suggests that PEG-IFN-α2b therapy may provide clinically significant overall survival benefit for selected high-risk patients.

The Florida Melanoma Trial I: A Prospective Multicenter Phase I/II Trial of Postoperative Hypofractionated Adjuvant Radiotherapy with Concurrent Interferon-Alfa-2b in the Treatment of Advanced Stage III Melanoma with Long-Term Toxicity Follow-Up

Radiotherapy (RT) and interferon-alfa-2b (IFN α-2b) have individually been used for adjuvant therapy stage III melanoma with high-risk pathologic features. We hypothesized that concurrent adjuvant RT and IFN α-2b may decrease the risk of regional recurrence following surgery with acceptable toxicity. A prospective multicenter phase I/II study was conducted to evaluate hypofractionated RT with concurrent IFN. Induction IFN α-2b, 20 MU/m2/d, was administered IV ×5 consecutive days every week for 4 weeks. Next, RT 30 Gy in 5 fractions was given with concurrent IFN α-2b, 10 MU/m2 SQ 3 times per week on days alternating with RT. Subsequent maintenance therapy consisted of adjuvant IFN α-2b, 10 MU/m2 SQ 3 times per week to a total of 1 year. To fully evaluate patterns of failure, long-term follow-up was conducted for up to 10 years. A total of 29 consenting patients were enrolled between August 1997 and March 2000. The maximum (worst) grade of acute nonhematologic toxicity during concurrent RT/IFN α-2b (and up to 2 weeks post RT) was grade 3 skin toxicity noted in 2 patients (9%). Late effects were limited. Probability of regional control was 78% (95% CI: 55%–90%) at 12 months. The median follow-up (range) was 80 (51–106) months among ten survivors (43%). The median overall survival was 34.5 months while the median failure-free survival was 19.9 months. Postoperative concurrent hypofractionated RT with IFN α-2b for advanced stage III melanoma appears to be associated with acceptable toxicity and may provide reasonable in-field control in patients at high risk of regional failure.

Outcomes for lymph node-positive cutaneous melanoma over two decades

BACKGROUND

Our aim was to demonstrate that, despite advances in treatment and surveillance of node-positive cutaneous melanoma, rates of overall survival (OS) and melanoma-specific survival (MSS) have not changed over the last two decades.

METHODS

We used the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute to identify patients with node-positive cutaneous melanoma. Patients were categorized by treatment era; the first era encompassed patients diagnosed from 1988 to 1999 and the second era 2000 to 2006. Multivariate Cox proportional hazards models compared rates of OS and MSS between treatment eras while controlling for known prognostic factors. We reported risks of death as hazard ratios (HR) with 95% confidence intervals (CI) and set significance at P≤0.05.

RESULTS

Entrance criteria were met by 6,868 patients, 1,631 (23.8%) treated in era I and 5,237 (76.3%) treated in era II. On multivariate analysis, era II patients did not demonstrate a significantly different risk of death from any cause (HR 0.89, CI 0.79-1.01; P<0.08), but they did have a lower risk of melanoma-specific mortality (HR 0.81, CI 0.71-0.93; P=0.003) relative to their era I counterparts.

CONCLUSIONS

Over nearly two decades, MSS but not OS has improved for AJCC stage III melanoma patients. Stage migration is likely responsible for any improvement in MSS among patients in the most recently diagnosed era.

Future of radiation therapy for malignant melanoma in an era of newer, more effective biological agents

The incidence of melanoma is rising. The primary initial treatment for melanoma continues to be wide local excision of the primary tumor and affected lymph nodes. Exceptions to wide local excision include cases where surgical excision may be cosmetically disfiguring or associated with increased morbidity and mortality. The role of definitive or adjuvant radiotherapy has largely been relegated to palliative measures because melanoma has been viewed as a prototypical radiotherapy-resistant cancer. However, the emerging clinical and radiobiological data summarized here suggests that many types of effective radiation therapy, such as radiosurgery for melanoma brain metastases, plaque brachytherapy for uveal melanoma, intensity modulated radiotherapy for melanoma of the head and neck, and adjuvant radiotherapy for selected high-risk, node-positive patients can improve outcomes. Similarly, although certain chemotherapeutic agents and biologics have shown limited responses, long-term control for unresectable tumors or disseminated metastatic disease has been rather disappointing. Recently, several powerful new biologics and treatment combinations have yielded new hope for this patient group. The recent identification of several clinically linked melanoma gene mutations involved in mitogen-activated protein kinase (MAPK) pathway such as BRAF, NRAS, and cKIT has breathed new life into the drive to develop more effective therapies. Some of these new therapeutic approaches relate to DNA damage repair inhibitors, cellular immune system activation, and pharmacological cell cycle checkpoint manipulation. Others relate to the investigation of more effective targeting and dosing schedules for underutilized therapeutics, such as radiotherapy. This paper summarizes some of these new findings and attempts to give some context to the renaissance in melanoma therapeutics and the potential role for multimodality regimens, which include certain types of radiotherapy as aids to locoregional control in sensitive tissues.

Role of radiation therapy in cutaneous melanoma

Cutaneous melanoma is a disease that often has an aggressive and unpredictable course. It was historically thought to be a radioresistant neoplasm; however, substantial radiobiologic and clinical evidence has emerged to refute this notion. Improved local control has been demonstrated with the use of adjuvant radiation therapy delivered to the primary site or regional lymphatics in patients with high-risk clinical or pathologic features. Despite improved local control, high-risk cutaneous melanoma often spreads systemically, leading to poor survival. In the setting of systemic progression, radiation therapy can frequently palliate symptomatic sites of metastatic disease.

Toxicity of combined treatment of adjuvant irradiation and interferon alpha2b in high-risk melanoma patients

Surgically resected stage III melanoma patients commonly receive adjuvant therapy with interferon (IFN) alpha2b. For those patients with high-risk features of draining node recurrence, radiation therapy can also be considered as a treatment option. The purpose of this retrospective study was to assess the efficacy and radiation-related toxicity of this combined therapy. Eighteen patients receiving adjuvant IFNalpha2b therapy during radiation therapy, or within 1 month of its completion, were reviewed retrospectively and analysed for outcome. Radiation was delivered at 600 cGy dose per fraction, in 16 out of 18 patients, twice a week, and at 200 cGy dose per fraction in two patients five times a week. Total radiation dose and number of fractions were as follows: 30 Gy/5 fr (n=8), 36 Gy/6 fr (n=8) and 50 Gy/25 fr (n=2). The percentage of disease-free patients, with no local recurrence, at 3 years was 88%. In 10 patients, IFNalpha2b was administered concurrently with radiotherapy; in three, within 30 days before or after radiation; and in five, more than 30 days after radiation. All the patients experienced acute skin reactions, grade I on the Radiation Therapy Oncology Group (RTOG) scale. Late radiation-related toxicity was seen in one patient with grade III (RTOG) skin reaction and two with grade IV (RTOG) radiation-induced myelitis. Concurrent use of adjuvant radiotherapy and IFNalpha2b might enhance radiation-induced toxicity, and special care should be taken when the spinal cord is included in the radiation field.