Total skin electron beam irradiation in scleromyxoedema

Scleromyxedema treatment: a systematic review and update

IMPORTANCE

Scleromyxedema is a chronic disease with high morbidity and mortality and no definitive therapeutic guidelines.

OBJECTIVE

To review all available data on the efficacy and the safety of the available treatments of scleromyxedema and suggest a possible therapeutic approach.

EVIDENCE REVIEW

We performed a systematic literature review in Pubmed/Medline, Embase, and Cochrane collaboration databases, searching for all articles since 1990 on the treatments of scleromyxedema, with no limits on participant age, gender, or nationality.

FINDINGS

Ninety-seven studies were included in this systematic review, of which one prospective, two retrospective, 70 case reports/case series, and 24 letters/correspondence/clinical image. Intravenous immunoglobulin (IVIG) was the most used first-line therapy based on its efficacy and its generally well-tolerated nature; most patients require continued treatment to remain in remission. Thalidomide and systemic glucocorticoids were mostly considered as second-line therapies and were given alone or in association with IVIG. Patients with severe or refractory disease were treated with autologous bone marrow transplantation, melphalan, or bortezomib with dexamethasone.

CONCLUSIONS AND RELEVANCE

Consideration of patient comorbidities, disease distribution, clinician experience, and treatment accessibility is mandatory in every therapeutic approach of scleromyxedema.

Scleromyxedematous Changes in a Patient With Long-Standing Mycosis Fungoides Who Progressed to Sézary Syndrome

Mycosis fungoides (MF) variants with different clinicopathologic and immunohistochemical features have been well-delineated. We report a case of scleromyxedematous changes arising in a patient with long-standing MF who progressed to Sézary syndrome (SS) shortly afterward. Total-skin electron-beam radiation therapy resulted in an excellent response, controlling both the MF/SS and the scleromyxedematous lesions; however, the patient died few months later. Although mucin deposition has been described in association with MF/SS (mainly follicular mucinosis in folliculotropic MF), there are limited reports in the literature on dermal mucinosis and scleromyxedematous changes in MF/SS. The mechanism of this association and its prognostic implications requires further investigation.

Dosimetric comparison of 4 MeV and 6 MeV electron beams for total skin irradiation

BACKGROUND

In this study, dosimetric aspects of TSEI consisting of a 4 MeV beam with no spoiler were investigated in comparison to a nominal 6 MeV beam with spoiler, and the potential for clinical applications was evaluated.

METHODS

The TSEI technique is based on the Stanford technique, which utilizes a beam configuration of six-dual fields. MOSFETs were used to measure the optimal gantry angle, profile uniformity, and absolute dose at the calibration point. The depth dose curve of the central axis was measured in the treatment plane using EBT2 film. Photon contamination was measured as the dose at 5 cm depth in a solid water phantom relative to the maximum dose using a parallel plate ion chamber. A MOSFET dosimeter placed on the surface of a humanoid phantom, and EBT2 films inserted into a humanoid phantom were used to verify the TSEI commissioning.

RESULTS

Dosimetric aspects of the 4 MeV TSEI beam, such as profile uniformity (±10%) and relative photon contamination (<0.001%), were comparable to those of a 6 MeV TSEI beam. The relative depth dose of the 4 MeV electrons was 81.4% at the surface and 100% at 0.4 cm. For the 6 MeV electrons, the relative depth dose was 93.4% at the surface and 100% from 0.2 cm to 0.4 cm. The calculated B-factor of the 4 MeV TSEI beam was 1.55, and 1.53 for the 6 MeV TSEI. 80% of the prescribed dose was obtained at 0.22 cm depth for the 4 MeV TSEI beam and 0.53 cm for the 6 MeV TSEI beam in the humanoid phantom measurement.

CONCLUSIONS

The suggested 4 MeV beam for TSEI could be applied to shallow depth skin diseases and to electron boost as second treatment course.

A technique for pediatric total skin electron irradiation

BACKGROUND

Total skin electron irradiation (TSEI) is a special radiotherapy technique which has generally been used for treating adult patients with mycosis fungoides. Recently, two infants presented with leukemia cutis isolated to the skin requiring TSEI. This work discusses the commissioning and quality assurance (QA) methods for implementing a modified Stanford technique using a rotating harness system to position sedated pediatric patients treated with electrons to the total skin.

METHODS AND RESULTS

Commissioning of pediatric TSEI consisted of absolute calibration, measurement of dosimetric parameters, and subsequent verification in a pediatric patient sized cylindrical phantom using radiographic film and optically stimulated luminance (OSL) dosimeters. The depth of dose penetration under TSEI treatment condition was evaluated using radiographic film sandwiched in the phantom and demonstrated a 2 cm penetration depth with the maximum dose located at the phantom surface. Dosimetry measurements on the cylindrical phantom and in-vivo measurements from the patients suggested that, the factor relating the skin and calibration point doses (i.e., the B-factor) was larger for the pediatric TSEI treatments as compared to adult TSEI treatments. Custom made equipment, including a rotating plate and harness, was fabricated and added to a standard total body irradiation stand and tested to facilitate patient setup under sedated condition. A pediatric TSEI QA program, consisting of daily output, energy, flatness, and symmetry measurements as well as in-vivo dosimetry verification for the first cycle was developed. With a long interval between pediatric TSEI cases, absolute dosimetry was also repeated as part of the QA program. In-vivo dosimetry for the first two infants showed that a dose of ± 10% of the prescription dose can be achieved over the entire patient body.

CONCLUSION

Though pediatric leukemia cutis and the subsequent need for TSEI are rare, the ability to commission the technique on a modified TBI stand is appealing for clinical implementation and has been successfully used for the treatment of two pediatric patients at our institution.

A conceptual design of rotating board technique for delivering total skin electron therapy

PURPOSE

This study presents a novel technique in which a uniform radiation dose to the whole body, soles, and scalp vertex can be achieved in one electron beam treatment fraction.

METHODS

The patient was treated at a machine with a home-made rotating board. The patients were treated in two groups in the prone and supine positions by leaning onto an inner rotational board in the prone and supine positions. Each group can further be separated into two subgroups using tilting and rotational positions for treatment.

RESULTS

One of the beams was directed 15.5 degrees upward and 15.5 degrees downward from the horizontal axis to provide a field size of as large as 200 cm in height and 140 cm in width. An incline angle of 31.5 degrees anteriorly (forward) or posteriorly (backward) of the outer frame at an angle rotated 60 degrees clockwise or counterclockwise to the inner frame was found to be most appropriate. The output for the rotating board total skin electron therapy (RB-TSET) was 0.046 cGy/MU at ISD of 350 cm. The beam characteristics of the RB-TSET depth dose curves were R50 = 2.48 cm, dmax = 0.7 cm, E0 = 5.78 MeV, and Rp = 3.4 cm.

CONCLUSIONS

The RB-TSET technique presented in this study is able to deliver a uniform radiation dose to the patient's skin surface, the scalp vertex, and soles of the feet all at one time, eliminating the trouble of having to further irradiate these two regions separately when using the Stanford six field technique.

Treatment of scleromyxoedema with hydroxychloroquine

BACKGROUND

Scleromyxoedema is a rare disease of unknown aetiology that is characterized by deposition of mucin and sclerotic induration of the skin; it is associated with paraproteinaemia. Patients suffer from progressive disability due to immobilization and cosmetic disfigurement. Treatment of scleromyxoedema is a therapeutic challenge. The antimalarial hydroxychloroquine has a rapid and reliable effect in reticular erythematous mucinosis.

PATIENTS AND METHODS

Four consecutive patients (two women, two men; median age: 50 years) with scleromyxoedema, three of them with IgG lambda paraprotein, were treated with hydroxychloroquine. Treatment was initiated with 600 mg p.o. for 10 days, followed by 400 mg for at least 4 weeks, and 200 mg thereafter.

RESULTS

Complete remission of skin manifestations was achieved in one patient, whereas three patients achieved a partial remission of 61+, 5 and 25 months' duration. Notably, three patients felt increased mobility and reduced firmness of skin during the first week of treatment, which was reflected in a rapid reduction in dermal thickness. In one patient, dysphagia was reverted as evidenced by normalization of oesophageal clearance. Paraproteinaemia was not influenced at all. Side effects included one case of electroretinogram abnormalities after 19 months of therapy and one case of leucopenia after 3 months.

CONCLUSION

Hydroxychloroquine is an effective form of therapy for scleromyxoedema, leading to rapid and prolonged alleviation of symptoms.