Impact of Radiation Therapy Modalities on Loco-regional Control in Inflammatory Breast Cancer.

PURPOSE: In inflammatory breast cancer, radiation therapy intensification is considered a standard of care by some teams, although the level of evidence remains low. We sought to analyze the impact of radiation therapy modalities on the risk of loco-regional and distant relapse. METHODS AND MATERIALS: This retrospective multicenter study included patients with localized inflammatory breast cancer treated between 2010 and 2017. Standard postmastectomy radiation therapy consisted of daily fractions to a total dose of 50 Gy equivalent without a boost or bolus, while intensified radiation therapy referred to the use of a boost or bolus. The cumulative incidence curves of locoregional and distant recurrence were displayed using the competing risk method. RESULTS: Of the 241 included patients, 165 were treated with standard and 76 with intensified radiation therapy. There was significantly more nodal involvement in the intensified group. With a median follow-up of 40 months postradiation therapy, there was no difference between standard versus intensified radiation therapy regarding the cumulative incidence of locoregional (P = .68) or distant recurrence (P = .29). At 5 years, the risks of locoregional and distant recurrence were 12.1% (95% CI, 7.5; 17.7) and 29.4% (95% CI, 21.8; 37.3) for patients treated with standard radiation therapy and 10.4% (95% CI, 4.4; 19.3) and 21.4% (95% CI, 12.6; 31.9) for those treated with intensified radiation therapy. In multivariate analyses, triple-negative subtype and absence of complete pathologic response were associated with a higher risk of loco-regional recurrence. Radiation therapy intensification had no significant impact on locoregional and distant recurrence. For patients with a non-complete pathologic response (n = 172, 71.7%), no significant differences were observed between the 2 groups for loco-regional (P = .80) and distant (P = .39) recurrence. Severe toxicity rates were similar in both groups. CONCLUSIONS: Contrary to other important series, this large retrospective multicentric study did not show a locoregional or distant control benefit of intensified radiation therapy. Pooled prospective studies and meta-analyses of intensified radiation therapy are warranted to endorse this approach.

The Sentinel Lymph Node in Treatment Planning: A Narrative Review of Lymph-Flow-Guided Radiotherapy.

The sentinel lymph node technique is minimally invasive and used routinely by surgeons, reducing the need for morbid extensive lymph node dissections, which is a significant advantage for cancer staging and treatment decisions. The sentinel lymph node could also help radiation oncologists to identify tumor drainage for each of their patients, leading to a more personalized radiotherapy, instead of a probabilistic irradiation based on delineation atlases. The aim is both to avoid recurrence in unexpected areas and to limit the volume of irradiated healthy tissues. The aim of our study is to evaluate the impact of sentinel lymph node mapping for radiation oncologists. This concept, relying on sentinel lymph node mapping for treatment planning, is known as lymph-flow-guided radiotherapy. We present an up-to-date narrative literature review showing the potential applications of the sentinel lymph node technique for radiotherapy, as well as the limits that need to be addressed before its routine usage.

Phase 1 Study of the Combination of Escalated Total Marrow Irradiation Using Helical Tomotherapy and Fixed High-Dose Melphalan (140 mg/m²) Followed by Autologous Stem Cell Transplantation at First Relapse in Multiple Myeloma.

PURPOSE: A second intensification is an option at first relapse in multiple myeloma (MM) after more than 36 months of initial remission. Many conditioning regimens have been tested, with or without total body irradiation (TBI). Recently, it was found that TBI could be replaced by total marrow irradiation (TMI) using helical tomotherapy, with promising results. METHODS AND MATERIALS: This study was a prospective multicenter phase 1 trial that aimed to determine the maximum tolerated dose (MTD) of TMI administered in association with melphalan 140 mg/m², followed by autologous stem cell transplantation as consolidation at first relapse in MM. Four dose levels were explored: 8 Gy, 10 Gy, 12 Gy, and 14 Gy. The dose-limiting toxicity (DLT) was defined as grade 4 neutropenia >15 days, grade 4 thrombopenia >28 days, and all other grade 4 nonhematologic toxic effects except nausea, vomiting, alopecia, mucositis, and reaction to autologous stem cell infusion. RESULTS: Thirteen patients were included; only 1 DLT at the third escalated dose level (12 Gy) was observed, whereas 1 patient was treated at 14 Gy with no adverse events. The MTD was not reached. The rate of acute toxicity was low: 38% of grade 3-4 diarrhea, mucositis, or unexplained fever. Regarding the lungs, the mean dose administered was systematically less than 8 Gy. After a median follow-up of 55 months, 70% of participants were alive. Of these 13 patients, 38.5% were in very good partial response and 30.8% were in complete response. Three of them were progression-free. Six patients were long survivors, still alive after 55 months of follow-up. CONCLUSIONS: Total marrow irradiation provides good results with a good tolerance profile at first relapse in MM and makes it possible to increase the dose delivered to the planning target volume while sparing organs at risk. This technique could be discussed for all regimens before auto- or allo-stem cell rescue when TBI is required.

Extramedullary hematopoiesis causing spinal cord compression in polycythemia vera: A case report and literature review.

Extramedullary hematopoiesis (EMH) is a rare cause of spinal cord compression defined as finding hematopoietic elements outside the physiological location in the bone marrow. We report the case of a 70-year-old man with JAK 2 positive myeloproliferative syndrome type polycythemia vera (PV), initially treated with hydroxyurea. Two years after diagnosis, he presented progression with biological and clinical evolution associating hyperleukocytosis and hepatosplenomegaly with no evidence of acute myeloid leukemia. Treatment with hydroxyurea and ruxolitinib was introduced. Six months later, clinical symptoms suggesting spinal cord compression from the T2 region appeared. Medullary MRI revealed a multistage spinal cord injury from T2 to S1, while brain CT excluded any intracranial location. The biopsy diagnosed extramedullary hematopoiesis with no CD34 + blast cell, corresponding polycythemia vera. Given the lack of consensus and after a review of the literature, irradiation was planned to treat a volume from T1 to S2 with a dose of 18 Gy in 10 sessions of 1.8 Gy. At the end of the radiotherapy, the patient started to recover his motor and sensory functions. Six months later, he walked without assistance and had no significant acute toxicity. Using radiotherapy to treat spinal cord compression caused by EMH is justified with excellent early response and no major side effects. We present here this case and the systematic review of the literature on this matter.

Different Prognostic Values of Tumour and Nodal Response to Neoadjuvant Chemotherapy Depending on Subtypes of Inflammatory Breast Cancer, a 317 Patient-Study.

Inflammatory breast cancer (IBC) is a rare entity with a poor prognosis. We analysed the survival outcomes of patients with nonmetastatic IBC and the prognostic value of tumour or nodal responses to assess their individual prognostic impact across IBC subtypes. This retrospective multicentre study included patients diagnosed with IBC between 2010 and 2017 to account for advances in neoadjuvant systemic therapies and modern radiotherapy at seven oncology centres in France. Three hundred and seventeen patients were included and analysed. After a median follow-up of 52 months, the 5-year DFS was lower for triple-negative (TN) (50.1% vs. 63.6%; p < 0.0001). After multivariate analyses, incomplete nodal response was the only significant prognostic factor in the triple-negative group (HR:6.06). The poor prognosis of TN-IBC was reversed in the case of nodal response after neoadjuvant chemotherapy. Breast response does not appear to be a decisive prognostic factor in patients with TN-IBC compared to lymph node response. Despite improvements in neoadjuvant treatments, IBC remains associated with a poor prognosis. In TN-IBC patients, lack of pathological complete node response was associated with poorer survival than any other group. Treatment intensification strategies are worth investigating.

Cytokine release syndrome and tumor lysis syndrome in a multiple myeloma patient treated with palliative radiotherapy: A case report and review of the literature.

We present the case of a 53-year-old woman treated with analgesic radiotherapy for a multiple myeloma bone lesion of the forearm. After a first fraction of 5 Gray (Gy), she presented with an acute respiratory syndrome with fever a few hours after the treatment. The same symptoms occurred after the second fraction 3 days later. The patient recovered quickly thanks to intravenous hydration and suspension of the radiotherapy. Biological tests revealed a tumor lysis syndrome. We concluded that the clinical symptoms could be defined as cytokine release syndrome. This is the second time in the literature that cytokine release syndrome has been described following radiotherapy. First, we synthesize TLS and radiotherapy to determine how radiotherapy could be a trigger associated with other well-known factors. Furthermore, we discuss radiotherapy and cytokine release syndrome. SUMMARY: We present the case of a woman treated with analgesic radiotherapy for a multiple myeloma bone lesion. Following the first and the second treatment fraction, the patient presented with an acute respiratory syndrome with fever and biological tests revealed a tumor lysis syndrome. We concluded that the clinical symptoms could be defined as cytokine release syndrome. Furthermore, we discuss how radiotherapy could be a trigger of cytokine release syndrome and tumor lysis syndrome in association with chemotherapy drugs.

Drug Intensification in Future Postoperative Radiotherapy Practice in Biochemically-Relapsing Prostate Cancer Patients.

Although salvage prostate bed radiotherapy is highly effective in biochemically-relapsing prostate cancer patients following prostatectomy, relapses remain frequent and improvements are needed. Randomized phase 3 trials have shown the benefit of adding androgen-depriving therapy to irradiation, but not all patients benefit from this combination. Preclinical studies have shown that novel agents targeting the androgen receptor, DNA repair, PI3K/AKT/mTOR pathways, or the hypoxic microenvironment may help increase the response to prostate bed irradiation while minimizing potential side effects. This perspective review focuses on the most relevant molecules that may have an impact when combined with salvage radiotherapy, and underlines the strategies that need to be developed to increase the efficacy of salvage post-prostatectomy radiotherapy in prostate cancer patients.