Low-dose total skin electron beam therapy for cutaneous lymphoma : Minimal risk of acute toxicities

Pharmaceutical management of acute radiation dermatitis in the German speaking radiation oncology community

BACKGROUND

Radiation dermatitis (RD) remains the most common side effect in radiation therapy (RT) with various pharmaceutical options available for prevention and treatment. We sought to determine pharmaceutical management patterns of radiation dermatitis among radiation oncology professionals.

METHODS

We conducted a survey on RD among the German-speaking community of radiation oncologists inquiring for their opinion on preventive and therapeutic pharmaceutical approaches for acute RD.

RESULTS

244 health professionals participated. Dexpanthenol lotion is the agent most widely used both for prevention (53.0%) and treatment (76.9%) of RD, followed by urea (29.8%) for prevention and corticosteroids (46.9%) for treatment. A wide range of substances is used by participants, though the overall experience with them is rather limited. 32.5% of participants do generally not recommend any preventative treatment. 53.4% of participants recommend alternative medicine for RD management. While seldomly used, corticosteroids were considered most effective in RD therapy, followed by dexpanthenol and low-level laser therapy. A majority of participants prefers moist over dry treatment of moist desquamation and 43.8% prescribe antiseptics.

CONCLUSIONS

Pharmaceutical management of RD in the German-speaking radiation oncology community remains controversial, inconsistent, and partially not supported by evidence-based medicine. Stronger evidence level and interdisciplinary consensus is required amongst practitioners to improve these care patterns.

Pharmazeutische Behandlung der akuten Radiodermatitis in der deutschsprachigen strahlentherapeutischen Gemeinschaft: Pharmaceutical management of acute radiation dermatitis in the German speaking radiation oncology community

Hintergrund

Die Radiodermatitis (RD) ist die häufigste Nebenwirkung der Strahlentherapie (RT), wobei verschiedene pharmazeutische Optionen zur Vorbeugung/Behandlung zur Verfügung stehen. Unser Ziel war, die pharmazeutischen Behandlungsmuster für die RD unter strahlentherapeutischen Fachleuten zu ermitteln.

Methodik

Wir haben eine Umfrage zum Thema RD in der deutschsprachigen radioonkologischen Gemeinschaft durchgeführt und ihre Meinung zu präventiven und therapeutischen pharmazeutischen Therapieansätzen betreffend die akute RD erfragt.

Ergebnisse

244 Angehörige zugehöriger Gesundheitsberufe nahmen teil. Dexpanthenol‐Lotion ist das am häufigsten verwendete Mittel sowohl zur Vorbeugung (53%) als auch zur Behandlung (76,9%) der RD, gefolgt von Harnstoff (29,8%) zur Vorbeugung und Kortikosteroiden (46,9%) zur Behandlung. Die Teilnehmer verwenden eine breite Palette an Substanzen, haben aber insgesamt wenig Erfahrung mit diesen. 32,5% der Teilnehmer empfehlen generell keine präventive Behandlung. 53,4% der Teilnehmer empfehlen Alternativmedizin. Obwohl selten eingesetzt, wurden Kortikosteroide als wirksamstes Behandlungsmittel angesehen, gefolgt von Dexpanthenol und Low‐Level‐Lasertherapie. Die Mehrheit der Teilnehmer bevorzugt die feuchte gegenüber der trockenen Behandlung der feuchten Desquamation und 43,8% verschreiben Antiseptika.

Schlussfolgerungen

Die pharmazeutische Behandlung der RD in der deutschsprachigen strahlentherapeutischen Fachwelt ist nach wie vor umstritten, sowie mitunter inkonsistent und nicht durch evidenzbasierte Medizin gestützt. Ein interdisziplinärer Konsens ist erforderlich, um die bestehenden Behandlungskonzepte zu verbessern.

The evolving role of reduced-dose total skin electron beam therapy in skin malignancies: the renaissance of a rare indication

Definitive radiation therapy is an effective local treatment for several cutaneous malignancies. Patients with diffuse or generalized skin manifestations might require total skin electron beam therapy (TSEBT) as an alternative treatment to the chasing technique. In this short communication, we highlight the evolving role of TSEBT and present its role in various forms of skin malignancies.

Ultrahypofractionated Low-Dose Total Skin Electron Beam in Advanced-Stage Mycosis Fungoides and Sézary Syndrome

PURPOSE

The aim of this study was to assess the safety and efficacy of an ultrahypofractionated low-dose total skin electron beam therapy (TSEBT) regimen in patients with advanced mycosis fungoides (MF) or Sézary syndrome (SS).

METHODS AND MATERIALS

In this multicenter observational study from 5 German centers, 18 total patients with MF or SS underwent TSEBT with a total dose of 8 Gy in 2 fractions. The primary endpoint was the overall response rate.

RESULTS

Fifteen of 18 patients with stage IIB-IV MF or SS were heavily pretreated with a median of 4 prior systemic therapies. The overall response rate was 88.9% (95% confidence interval [CI], 65.3-98.6), with 3 complete responses (16.9%; 95% CI, 3.6-41.4). At a median follow-up period of 13 months, the median time to next treatment (TTNT) was 12 months (95% CI, 8.2-15.8), and the median progression-free survival was 8 months (95% CI, 2-14). A significant reduction in the modified severity-weighted assessment tool, total Skindex-29 score (Bonferroni-corrected P < .005), and all subdomains (Bonferroni-corrected P < .05) was observed after TSEBT. Half of the irradiated patients (n = 9) developed grade 2 acute and subacute toxicities. One patient had confirmed grade 3 acute toxicity. Chronic grade 1 toxicity has been observed in 33% of patients. Patients with erythroderma/SS or prior radiation therapy appear at higher risk of skin toxicities.

CONCLUSIONS

TSEBT with 8 Gy in 2 fractions achieves good disease control and symptom palliation with acceptable toxicity, greater convenience, and fewer hospital visits.

Total Skin Treatment with Helical Arc Radiotherapy

For widespread cutaneous lymphoma, such as mycosis fungoides or leukemia cutis, in patients with acute myeloid leukemia (AML) and for chronic myeloproliferative diseases, total skin irradiation is an efficient treatment modality for disease control. Total skin irradiation aims to homogeneously irradiate the skin of the entire body. However, the natural geometric shape and skin folding of the human body pose challenges to treatment. This article introduces treatment techniques and the evolution of total skin irradiation. Articles on total skin irradiation by helical tomotherapy and the advantages of total skin irradiation by helical tomotherapy are reviewed. Differences among each treatment technique and treatment advantages are compared. Adverse treatment effects and clinical care during irradiation and possible dose regimens are mentioned for future prospects of total skin irradiation.

Changes in total skin electron beam therapy modalities for mycosis fungoides: A single-centre study

BACKGROUND

Mycosis fungoides (MF) is a highly radiosensitive disease. Total skin electron beam therapy (TSEBT) is an effective option that may allow prolonged response for several months. Recently, a low-dose regimen (12 Gy) has been reported more frequently, with less complete response than for standard doses (36 Gy) but better safety. Our aim was to compare patients treated with 12-Gy and 36-40-Gy TSEBT regimens at our centre for efficacy and safety.

METHODS

This retrospective, monocentric study in Bordeaux University Hospital included all MF patients treated with 12-Gy or 36-40-Gy TSEBT between 2011 and 2020.

RESULTS

Patients presented with MF at the following stages: 15 T2, including 9 folliculotropic MF; 2 T3, including 1 folliculotropic; 8 T4, including 2 Sézary syndromes. The mean follow-up time after TSEBT was 43.5 months [range: 2-128] for the 36-40-Gy group and 25.2 months [range: 4-45] for the 12-Gy group. The 3-month overall response rate (ORR) was similar for both groups (84.6% for 36-40 Gy and 91.7% for 12 Gy), but there was a tendency to more complete response in the 36-40-Gy group (30.8% vs 8.3%, P=0.35). Progression-free survival (PFS) tended to be better in the 36-40-Gy group than in the low-dose group (15.7 months vs 5.3 months; P=0.28). Patients treated with low-dose TSEBT had a lower incidence of radiation dermatitis (16.7% vs 38.4%, P=0.42).

CONCLUSION

We confirm that TSEBT is an effective option, including at lower doses. Differences between low- and standard-dose regimens were not significant in our series. Although a low-dose regimen seemed to result in lower complete response and long-term efficacy rates in comparison with a standard dose, treatment at lower doses presents the advantage of repeatability, with fewer and weaker side effects, in the event of disease recurrence. Second-line treatments were mostly skin-directed in this group.

In vivo dosimetry for testicular and scalp shielding in total skin electron therapy using a radiophotoluminescence glass dosimeter

Mycosis fungoides (MF) is a common, low-grade non-Hodgkin's lymphoma of skin-homing T lymphocytes that can be treated via skin-directed radiotherapy. Our institution has implemented total skin electron therapy (TSET) with a 4.3 m source-to-surface distance (SSD) and 6 MeV electron beams with a beam spoiler. A 35-year-old male undergoing TSET desired to avoid radiotherapy-induced hair loss and temporary infertility; therefore, leakage dose to scalp and testicles was reduced with a special radiation shield composed of stacked lead sheets. The shields for the scalp and scrotal were of 3 mm and 6 mm, respectively. To assess leakage doses, a radiophotoluminescence glass dosimeter (RPLD) was placed at every fraction. The difference dose between the measured and prescribed dose at the calibration point was 2%. The top of the head and scrotal surface exhibited 18 cGy and 10 cGy, respectively. Thus, the dose to the scrotal surface was not beyond the testicular tolerance dose of 20 cGy. Results of semen analysis two months postradiotherapy were normal. There was no hair loss during or after radiation therapy. Therefore, the RPLD is a useful in vivo dosimeter that provides technical information on radiation shielding to allow for completion of TSET without hair loss or temporary infertility.

Low-dose total skin electron beam therapy plus oral bexarotene maintenance therapy for cutaneous T-cell lymphoma

BACKGROUND

Total skin electron beam therapy (TSEBT) combined with systemic therapy or maintenance treatment is a reasonable approach to enhance the remission rate and duration in mycosis fungoides (MF) and Sézary syndrome (SS). This study assesses the efficacy of oral bexarotene therapy after low-dose TSEBT for patients with MF and SS.

METHODS

In this prospective observational study, we recruited MF/SS patients for treatment with low-dose total skin electron beam therapy (TSEBT) with or without bexarotene therapy to describe outcomes and toxicities.

RESULTS

Forty-six subjects with MF or SS underwent TSEBT between 2016 and 2021 at our institute. Following TSEBT, 27 patients (59 %) received oral bexarotene treatment. The median follow-up was 13 months. The overall response rate (ORR) for the cohort was 85 %. The response rate was significantly higher with combined modality (CM) than TSEBT alone (96 % vs. 68 %, p = 0.03). Median progression-free survival (PFS) for the CM was 17 months versus five months following TSEBT alone (p = 0.001). One patient (4 %) in the retinoid group discontinued the bexarotene therapy because of adverse events. The administration of bexarotene therapy did not increase radiation-related toxicities.

CONCLUSIONS

Response rate and progression-free survival might be improved with TSEBT in combination with oral bexarotene compared to TSEBT alone.

Sweeping-beam technique with electrons for large treatment areas as total skin irradiation : Dosimetric and technical aspects of a modified Stanford technique

PURPOSE

Total skin electron beam therapy (TSEBT) is still a technical and therapeutic challenge today. Thus, we developed TSEBT using a sweeping-beam technique.

METHODS

For treatment delivery, a linear accelerator Versa HD (ELEKTA, Stockholm, Sweden) with high-dose-rate electrons (HDRE) was used with a dose rate of 9000 MU/min. Dosimetry quality assurance was performed by multiple measurements with film dosimetry, 2D array, and Roos chamber.

RESULTS

Clinical experience shows that treatment durations of 75 to 90 min are usual for the Stanford technique without using HDRE. With this new sweeping-beam irradiation technique, the total treatment time of a daily fraction could be reduced to 20 min while keeping over- and underdosing low. The treatment area is about 60 cm × 200 cm and the dose distribution is uniform within 2% and 5% in vertical and horizontal directions, respectively. Initially, the electron energy of 6 MeV is reduced to 3.2 MeV by 1‑cm polymethylmethacrylat (PMMA) scatter and the irradiation conditions of a source-surface distance (SSD) of 350 cm. The photon contamination drops to under 1%.

CONCLUSION

These results show that the mean dose to total skin varies between 1.3 and 1.8 Gy. The sweeping-beam technique with electrons has a homogeneous dose distribution in connection with a short treatment time.

Acute and sub-acute toxicity profile of ultra-hypofractionated low-dose total skin electron beam with two 4 Gy fractions for cutaneous T cell lymphoma

Purpose

Low-dose total skin electron beam therapy (TSEBT) over 3 weeks has proved to be a safe and effective treatment for cutaneous T cell lymphomas (CTCL). In this prospective trial, we examined the feasibility of ultra-hypofractionated low-dose TSEBT regimen in two fractions with 4 Gy combined with systemic therapy to minimize the number of visits to radiation centers.

Patients and methods

Six patients with mycosis fungoides (MF) or Sézary syndrome (SS) received TSEBT with a total radiation dose of 8 Gy in two fractions between April 2020 and June 2020. Patient and treatment characteristics, tumor burden, the impact on the quality of life using Skindex-29 questionnaires, and acute toxicities were analyzed.

Results

During TSEBT, all patients developed grade 1 toxicities while two patients developed grade 2 toxicities. One patient experienced sepsis. The most common adverse effects were erythema and edema. All grade 2 toxicities regressed after 4 weeks following TSEBT. Based on the reported symptoms measured by Skindex-29, we detected a significant reduction in total Skindex-29 score after 8 weeks of radiation (P = 0.03), particularly in the symptoms (P = 0.01) and emotional domains (P = 0.04).

Conclusion

Ultra-hypofractionated low-dose TSEBT followed by systemic therapy seems to be a safe and feasible alternative to conventional fractionated TSEBT for patients with MF/SS. The skin tumor burden and the health-related quality of life have been significantly improved within 8 weeks following radiotherapy.

Maintenance Therapy for Cutaneous T-cell Lymphoma After Total Skin Electron Irradiation: Evidence for Improved Overall Survival With Ultraviolet Therapy

BACKGROUND

Treatment of cutaneous T-cell lymphoma (CTCL) with total skin electron beam (TSEB) therapy has been associated with deep responses but short progression-free intervals. Maintenance therapy might prolong the response duration; however, limited data assessing the outcomes with maintenance therapy after TSEB are available. We evaluated the effect of maintenance therapy on the outcomes for patients with CTCL receiving TSEB therapy.

MATERIALS AND METHODS

We conducted a single-center retrospective analysis of 101 patients with CTCL who had received TSEB therapy from 1998 to 2018 at the Winship Cancer Institute of Emory University and compared the overall survival (OS) and progression-free survival (PFS) for patients had received maintenance therapy, including retinoids, interferon, ultraviolet therapy, nitrogen mustard, and extracorporeal photopheresis compared with those who had not.

RESULTS

We found that pooled maintenance therapies improved PFS (hazard ratio [HR], 0.60; P = .026) but not OS (median HR, 0.73; P = .264). The median PFS and OS was 7.2 months versus 9.6 months and 2.4 years versus 4.2 years for the no maintenance and maintenance groups, respectively. On exploratory analysis of the individual regimens, ultraviolet therapy was associated with improved OS (HR, 0.21; P = .034) and PFS (HR, 0.26; P = .002) compared with no maintenance.

CONCLUSION

Among the patients with CTCL who had received TSEB therapy, maintenance therapy improved PFS for all patients, and ultraviolet-based maintenance improved both PFS and OS in a subset of patients.

Low-Dose Hypofractionated Total Skin Electron Beam Therapy for Adult Cutaneous T-Cell Lymphoma

Purpose

Historically, the standard of care for total skin electron beam therapy (TSEBT) delivered 30 to 36 Gy over 5 to 10 weeks. Given the high risk of relapse, a majority of patients require additional treatments. Therefore, attempts to use a shortened course of TSEBT have been investigated.

Methods and Materials

We conducted a single-institution retrospective review to evaluate disease response, control, and toxicity using a low-dose, hypofractionated course of TSEBT (HTSEBT) in patients with mycosis fungoides.

Results

Forty patients received 57 courses of HTSEBT. Median dose (Gy)/fractionation was 12/3, spanning a median time of 2.4 weeks. Overall response rate of patients assessed (n = 54) was 100%. Thirty-one courses (57.4%) resulted in a complete response and 23 courses (42.6%) resulted in a partial response. Cumulative incidence of progressive skin disease at 3 months was 37.2%, at 6 months, 56.9%, and at 1 year, 81.5%. Of the 40 patients treated with a first course of HTSEBT, 31 received subsequent courses of radiotherapy. Cumulative incidence of subsequent treatment was 28.0% at 3 months, 46.8% at 6 months, and 70.0% at 1 year. Patients who underwent repeat courses of HTSEBT continued to have similar treatment responses to repeat courses without increased toxicities. Toxicities from all courses were acceptable with the exception of 1 patient, who experienced grade 4 skin toxicity (moist desquamation requiring hospitalization).

Conclusions

Low-dose HTSEBT provides good palliation in patients with cutaneous T-cell lymphoma with a satisfactory response and toxicity profile. HTSEBT allows therapy to be completed in far fewer treatments. Low-dose HTSEBT is an appropriate treatment option for patients unable to come for daily treatment. HTSEBT provides a way to decrease exposure to other patients and staff during public health emergencies such as the coronavirus disease 2019 (COVID-19) pandemic.

Low dose total skin electron beam therapy for the management of T cell cutaneous lymphomas

Mycosis fungoides (MF) represent the most common type of primary cutaneous lymphomas. Total skin electron beam (TSEB) therapy to a total skin administered dose of 36 Gy represents a very effective treatment regimen and its role in the management of MF is well established. Unfortunately, the issue in MF is that despite the proved effectiveness of radiation therapy, disease regress, and the main goal of TSEB treatment seems to be the prolongation of the overall response duration time. Taking into consideration the high radio-sensitivity of the disease, lower radiation doses have been tested with acceptable and comparable results. We prospectively analyzed low dose TSEB in 14 patients treated at ATTIKON University Hospital from 2011 to 2017. After a median duration of follow up time of 39 months we found that low dose TSEB is an effective treatment option, since therapeutic results are more than acceptable, with minimal toxicity. The fact that it can be repeated safely in the natural course of a "regressive" disease makes it more attractive than the standard full dose scheme of 36 Gy.

Total skin electron beam therapy for primary cutaneous T-cell lymphomas: clinical characteristics and outcomes in a Mexican reference center

Aim

The aim of this study was to assess treatment modalities, treatment response, toxicity profile, disease progression and outcomes in 14 patients with a confirmed diagnosis of primary cutaneous T-cell lymphoma (PCTCL) treated with total skin electron beam therapy (TSEBT).

Background

Primary cutaneous lymphomas (PCLs) are extranodal non-Hodgkin lymphomas originating in the skin without evidence of extracutaneous disease at diagnosis. Despite advances in systemic and local therapy options, the management of advanced stages remains mostly palliative.

Materials and Methods

This is a retrospective study of patients with PCTCL, diagnosed and treated in a reference center in Mexico City, analyzing treatment modalities, response to treatment, long-term outcome, and mortality.

Results

Eight males (57%) and 6 (43%) females were identified. Most patients were stage IVA (n = 5, 36%) followed by stage IB and IIB (28.5% and 21.4%, respectively). Eleven patients received the low-dose RT scheme (12 Gy), 1 patient, the intermediate-dose RT scheme (24 Gy), and 2 patients, the conventional-dose RT scheme (36 Gy). Mean follow-up time was 4.6 years. At first follow-up examination, 6-8 weeks after radiotherapy, the overall response rate (ORR) for the cohort was 85%. The median PFS for the whole cohort was 6 months.

Conclusion

This study reinforces the role of TSEBT when compared with other treatment modalities and novel agents. Low-dose TSEBT is now widely used because of the opportunity for retreatment.

Ultra-Low-Dose Radiotherapy for Palliation of Mycosis Fungoides

Introduction. Mycosis fungoides (MF) is a form of primary cutaneous T-cell lymphomas, and radiotherapy (RT) has been used to treat localized/limited lesions of MF. In this case report, the results of low-dose RT applied for palliative purpose are shared. Case Report. A 70-year-old male patient was admitted to the outpatient clinic 7 months ago with a generalized itchy rash. The result of the biopsy was reported as mycosis fungoides. Systemic treatment was not performed due to comorbid diseases. The hemibody RT was applied. 2 Gy was given per fraction, with a total dose of 6 Gy. The significant clinical relief was observed with 6 Gy RT. The patient died due to multiorgan failure 2 months later, and no recurrence was observed. Conclusion. The palliation was achieved in the advanced MF patient with fractionated 6 Gy hemibody RT for the remaining 2 months of life.

Low-dose total skin electron beam therapy: Quality of life improvement and clinical impact of maintenance and adjuvant treatment in patients with mycosis fungoides or Sezary syndrome

PURPOSE

Total skin electron beam therapy (TSEBT) has proved to be a safe and effective treatment for cutaneous T‑cell lymphomas. Here, we examined the impact of this treatment on patient quality of life and outcome.

PATIENTS AND METHODS

Forty-four patients with mycosis fungoides (MF) or Sezary syndrome (SS) received 48 TSEBT courses with a median dose of 12 Gy within the past 8 years at our institute. Patient and treatment characteristics for these cases as well as the impact of TSEBT on quality of life and duration of response were retrospectively analyzed and compared.

RESULTS

The median modified Severity-Weighted Assessment Tool score before the start of TSEBT was 44. The overall response rate was 88%, with a complete response (CR) rate of 33%. The median follow-up period was 13 months. The median duration of response (DOR) and progression-free survival (PFS) for the entire cohort were 10 months and 9 months, respectively. Patient-reported symptom burden was measured with the Dermatological Life Quality Index and Skindex-29 questionnaires. The mean symptom reductions were 6 ± 8 (P = 0.005) and 21 ± 24 (P = 0.002), respectively. In the Functional Assessment of Cancer Therapy-General Assessment, significant improvements in the emotional (P = 0.03) domains were observed after TSEBT. Patients who received maintenance or adjuvant treatments had a longer PFS (P = 0.01).

CONCLUSION

TSEBT improved disease symptoms and significantly improved emotional domains of patients' quality of life in patients with MF or SS. In addition, our results indicate that maintenance or adjuvant therapy after TSEBT may improve the PFS.

Impact of radiation dose on local control and survival in extramedullary head and neck plasmacytoma

Background

Patients with plasma-cell neoplasia usually suffer from systemic disease, although a minority (< 5%) may present with solitary involvement of bone or soft tissue (extramedullary plasmacytoma (EMP)). Radiotherapy (RT) is a state-of-the-art treatment for these tumors offering long term curation.

Methods and materials

Between January 2005 and January 2017, twenty-seven patients underwent RT at our institution. The aim of this study was to analyse the effectiveness of various RT doses for different forms of EMP.

Results

A total of 33 radiation courses were administered to 27 patients with a median age of 56 years. The median RT dose was 45 Gy (range: 12–55.8). The local control rate was 76% (93% for primary EMP vs. 61% for the secondary EMP lesions; P < 0.05). A complete response (CR) rate to local RT was achieved for 42% lesions (67% for primary EMP vs. 22% for the secondary EMP lesions; P < 0.01). The overall response rate (ORR) for the EMP lesions treated with high-dose regimens (> 45 Gy) versus low-dose regimens (≤ 45 Gy) was 87% versus 67%, respectively (P = 0.2). The median survival with high-dose RT group was significantly longer (P = 0.02). In subgroups analysis, primary EMP patients treated with high-dose RT had a non-significant higher ORR (100% vs. 80%, respectively; P = 0.3,) longer duration of LC (P = 0.3) with a longer survival (P = 0.05) than patients in low-dose group. No significant difference has been detected in secondary EMP patients treated with high-dose RT regarding ORR (60% vs. 62%, respectively; P = 1), and survival (P = 0.4).

Conclusion

RT is an efficacious treatment modality in the treatment of EMP. A radiation dose ≤45 Gy confer a comparable CR rate to high-dose regimens and appears to be an effective treatment for controlling local EMP progression. Radiation dose-escalation may be beneficial for particular subgroups of patients.

Clinical application of Total Skin Electron Beam (TSEB) therapy for the management of T cell cutaneous lymphomas. The evolving role of low dose (12 Gy) treatment schedule

BACKGROUND & PURPOSE

Although rare, cutaneous lymphomas represent a separate entity in hematologic oncology. T cell origin lymphomas are most common, with Mycosis Fungoides (MF) accounting for about 50-70% of cases. Sezary Syndrome (SS), which represents the leukemic varian of MF, accounts for 3% of Cutaneous T Cell Lymphomas (CTCL). Total Skin Electron Beam Therapy (TSEB) is included at the mainstream of treatment choices for CTCL. The scope of this study is to evaluate the effectiveness and toxicity of two treatment schedules of TSEB.

METHODS AND MATERIALS

We report our experience with TSEB in the management of MF and SS, as of 14 patients treated in our institution from 2011 to 2015. 8 patients received the 12 Gy (low dose) scheme while 6 patients were managed with 36 Gy (standard or full dose scheme) according to six dual field Stanford technique. The endpoints were overall response rate, duration of response and toxicity of treatment.

RESULTS

After a median follow up of 2.5 years we noted excellent treatment outcome, with both schemes being well tolerated and resulting in comparable response rates. The overall response rate for both treatment regimens was over 87.5%. Treatment was well tolerated with mild toxicity.

CONCLUSION

The role of TSEB in the management of MF and SS is well established. The low dose TSEB schedule of 12 Gy is an effective treatment option, since therapeutic results are more than acceptable, compliance is excellent and toxicity is minimal. Moreover, the evidence that it can be repeated safely makes it more attractive than the standard 36 Gy scheme, when a patient is referred to radiation treatment according to treatment guidelines.

Extensive Cutaneous T-Cell Lymphoma of the Feet Treated with High-Dose-Rate Brachytherapy and External Beam Radiation

Cutaneous T-cell lymphoma (CTCL) is a chronic, debilitating disease that has a severe impact on quality of life. We present a patient with multiple CTCL lesions on the bilateral feet, which impaired his ability to ambulate. His lesions on both feet were successfully treated with a total of 8 Gy in two fractions via high-dose-rate surface brachytherapy using the Freiburg Flap applicator. The deeper aspects of the bulkier lesions on the left foot were boosted with electron beam therapy. The radiation therapy was well tolerated, and the patient was able to regain his mobility after completing radiation therapy. To our knowledge, there are few reports utilizing brachytherapy in treating CTCL. Our case describes treatment of larger, more extensive CTCL lesions than previously reported.

In-vivo dosimetric analysis in total skin electron beam therapy

Background and purpose

Thermoluminescent dosimetry (TLD) is an important element of total skin electron beam therapy (TSEBT). In this study, we compare radiation dose distributions to provide data for dose variation across anatomic sites.

Materials and methods

Retrospectively collected data on 85 patients with cutaneous lymphoma or leukemia underwent TSEBT were reviewed. Patients were irradiated on two linear accelerators, in one of two positions (standing, n = 77; reclined, n = 8) and 1830 in vivo TLD measurements were obtained for various locations on 76 patients.

Results

The TLD results showed that the two TSEBT techniques were dosimetrically heterogeneous. At several sites, the dose administered correlated with height, weight, and gender. After the first TLD measurement, fourteen patients (18%) required MU modification, with a mean 10% reduction (range, −25 to +35). Individual TLD results allowed us to customize the boost treatment for each patient. For patients who were evaluated in the standing position, the most common underdosed sites were the axilla, perineum/perianal folds, and soles (each receiving 69%, 20%, and 34% of the prescribed dose, respectively). For patients evaluated in a reclining position, surface dose distribution was more heterogeneous. The sites underdosed most commonly were the axilla and perineum/perianal folds (receiving less than one third of prescribed dose). Significant variables were detected with model building.

Conclusion

TLD measurements were integral to quality assurance for TSEBT. Dose distribution at several anatomical sites correlated significantly with gender, height, and weight of the treated individual and might be predicted.

Bone marrow suppression as a complication of total skin helical tomotherapy in the treatment of mycosis fungoides

Background

Total skin electron beam therapy (TSEBT) is an effective treatment in mycosis fungoides. Total skin helical tomotherapy (TSHT) may be an alternative to TSEBT and may offer several dosimetric and treatment advantages. There are currently very few published treatment results using TSHT in place of TSEBT for treatment of mycosis fungoides.

Case presentation

Two patients with mycosis fungoides were treated at our institution using TSHT. The first patient was a 69-year-old Caucasian female with stage IVA2 (T2 N3 M0 B2) disease who was treated to a dose of 12 Gy in 8 fractions, with a bone marrow mean dose of 1.66 Gy and V10 = 0.41%. Two weeks after ending treatment the patient developed myelosuppression including grade 4 thrombocytopenia and required blood and platelet transfusions. The second patient was a 29-year-old Caucasian female with stage I (T2 N0 M0 B0) disease. This patient previously had been treated for mycosis fungoides using helical tomotherapy (HT) at a dose of 20 Gy to a localized region and experienced mild thrombocytopenia at that time. The patient then underwent retreatment 17 months later with TSHT to a dose of 12 Gy in 6 fractions with a mean bone marrow dose of 2.3 Gy and V10 = 4.28%. This patient once again experienced myelosuppression that included grade 4 thrombocytopenia. She also required blood and platelet transfusions.

Conclusions

Both patients treated with TSHT experienced severe bone marrow suppression including grade 4 thrombocytopenia. This was more severe than expected considering the relatively low overall prescription dose and despite a planning constraint placed on the bone marrow of a mean dose of < 2 Gy. These outcomes suggest that patients treated using TSHT should be closely monitored for myelosuppression and caution used even when treating to a dose of 12 Gy.

Response rates and recurrence patterns after low-dose radiotherapy with 4 Gy in patients with low-grade lymphomas

PURPOSE

Retrospective study of effectiveness, toxicity, and relapse patterns after low-dose radiotherapy (LDRT) in patients with low-grade lymphomas.

METHODS

47 patients (median age 64 years) with 50 lesions were treated with LDRT (2 × 2 Gy). In 60%, LDRT was the primary and curative treatment, in 40% offered as second-line therapy in recurrent disease. Histology included follicular (57%) and marginal zone lymphomas (43%). Patients were followed-up regularly clinically (skin) and with CT or MRI scans.

RESULTS

Median follow-up was 21 months. 84% of the lesions were extranodal disease (32% orbit, 14% salivary glands, 30% skin, and 8% others). Most lesions were ≤5 cm (90%) with a singular affection (74%). 26% of the patients received rituximab simultaneously. Overall response rate (ORR) was 90% (all lesions), 93.3% (primary treatment), and 85% (recurrence treatment); p = 0.341. 2‑year Local progression-free survival (LPFS) for all, curative, and palliative patients was 91.1%, 96.7%, and 83.8%, respectively; p = 0.522. Five relapses were detected: three infield only, and were therefore treated with LDRT or subsequent local RT of 30 Gy. Two patients showed an in- and outfield progression and were consequently treated with chemotherapy. Predictive factors for higher LPFS were tumor size ≤5 cm (p = 0.003), ≤2 previous treatments (p = 0.027), no skin involvement (p = 0.05), singular affection (p = 0.075), and simultaneous rituximab application (p = 0.148). LDRT was tolerated well, without detectable acute or long-term side effects.

CONCLUSION

Primary LDRT is an effective treatment with high ORR and long-lasting remissions in a subset of patients with low-grade lymphoma, and may therefore be a curative treatment option for patients with low tumor burden. LDRT with the CD20 antibody obinutuzumab will soon be tested in a prospective multicenter trial.

Dose optimization of total or partial skin electron irradiation by thermoluminescent dosimetry

BACKGROUND

Due to the complex surface of the human body, total or partial skin irradiation using large electron fields is challenging. The aim of the present study was to quantify the magnitude of dose optimization required after the application of standard fields.

METHODS

Total skin electron irradiation (TSEI) was applied using the Stanford technique with six dual-fields. Patients presenting with localized lesions were treated with partial skin electron irradiation (PSEI) using large electron fields, which were individually adapted. In order to verify and validate the dose distribution, in vivo dosimetry with thermoluminescent dosimeters (TLD) was performed during the first treatment fraction to detect potential dose heterogeneity and to allow for an individual dose optimization with adjustment of the monitor units (MU).

RESULTS

Between 1984 and 2017, a total of 58 patients were treated: 31 patients received TSEI using 12 treatment fields, while 27 patients underwent PSEI and were treated with 4-8 treatment fields. After evaluation of the dosimetric results, an individual dose optimization was necessary in 21 patients. Of these, 7 patients received TSEI (7/31). Monitor units (MU) needed to be corrected by a mean value of 117 MU (±105, range 18-290) uniformly for all 12 treatment fields, corresponding to a mean relative change of 12% of the prescribed MU. In comparison, the other 14 patients received PSEI (14/27) and the mean adjustment of monitor units was 282 MU (±144, range 59-500) to single or multiple fields, corresponding to a mean relative change of 22% of the prescribed MU. A second dose optimization to obtain a satisfying dose at the prescription point was need in 5 patients.

CONCLUSIONS

Thermoluminescent dosimetry allows an individual dose optimization in TSEI and PSEI to enable a reliable adjustment of the MUs to obtain the prescription dose. Especially in PSEI in vivo dosimetry is of fundamental importance.