Radiation therapy in indolent primary cutaneous B cell lymphoma: a single institute experience

Success of Ultra-low Dose Radiation Therapy for Primary Cutaneous B-cell Lymphoma

OBJECTIVES

Primary cutaneous B-cell lymphoma (PCBCL) is a relatively rare disease, associated with 5-year overall survival of nearly 95% when treated with external beam radiation therapy (EBRT) alone. However, standard EBRT doses yield acute skin toxicity in more than 70% of patients and grade 3 to 4 acute skin toxicity in nearly 10% of patients. Consequently, the PCBCL treatment paradigm is shifting towards lower EBRT doses. This study evaluates our early experience with ultra-low dose EBRT (total dose of 4 Gy in 2 fractions) for PCBCL.

METHODS

Four biopsy-confirmed PCBCL lesions (1 anterior thigh and 3 chest) in 2 male patients were treated with 2 Gy×2 fraction EBRT using electrons through a clinical setup. The anterior thigh lesion was treated using a clamshell to protect the scrotum from scatter dose. Treatment was achieved using 9 MeV electrons to the 85% isodose line using no bolus, with follow-up every 4 months and potential retreatment if no visible response at 8 to 9 months.

RESULTS

All lesions demonstrated a response to EBRT by 4 months, visibly manifesting as flattening with changes in pigmentation. At the last follow-up (20, 20, 16.5, and 4 mo, respectively), all lesions had flattened with no evidence of local recurrence and no skin toxicity.

CONCLUSIONS

Treatment of PCBCL with ultra-low dose EBRT to 4 Gy total dose in 2 fractions provides durable local control with zero skin toxicity. These results are encouraging for both the success of treatment and the potential to use similarly low doses for retreatment should patients exhibit local recurrence.

Fibrin-Associated Diffuse Large B Cell Lymphoma Found on Revision Arthroplasty of the Knee

Fibrin-associated diffuse large B cell lymphoma (FA-DLBCL) is a rare Epstein-Barr viruspositive B cell lymphoma that is nonmass-forming, does not directly produce symptoms, and is incidentally discovered on histological examination of tissues excised for other reasons. Despite overlap in morphologic and immunophenotypic features with aggressive B cell neoplasms, FA-DLBCL shows an excellent clinical outcome, even with surgical excision alone. We report an extremely rare occurrence of FA-DLBCL found in association with a metallic implant on revision arthroplasty of the knee. This report also illustrates the need for an integrated multidisciplinary approach for accurate diagnosis and avoidance of overtreatment.

The role of radiation therapy in the management of cutaneous malignancies. Part II: When is radiation therapy indicated?

Radiation therapy may be performed for a variety of cutaneous malignancies, depending on patient health status, tumor clinical and histologic features, patient preference, and resource availability. Dermatologists should be able to recognize the clinical scenarios in which radiation therapy is appropriate, as this may reduce morbidity, decrease risk of disease recurrence, and improve quality of life. The second article in this 2-part continuing medical education series focuses on the most common indications for radiation therapy in the treatment of basal cell carcinoma, cutaneous squamous cell carcinoma, dermatofibrosarcoma protuberans, Merkel cell carcinoma, Kaposi sarcoma, angiosarcoma, cutaneous lymphoma, melanoma, undifferentiated pleomorphic sarcoma, and sebaceous carcinoma.

The prognostic role of age in primary cutaneous B-cell lymphoma: a proposal derived from a population-based registry

PURPOSE

A few prognostic predicting systems existed for primary cutaneous B-cell lymphoma (PCBCL). However, none of them took age into consideration. We sought to declare the prognostic role of age in PCBCL.

MATERIALS AND METHODS

A total of 4859 patients were identified in the surveillance, epidemiology and end results data, spanning 1975-2016. The association between age and survival was determined using unadjusted and adjusted proportional hazard analysis.

RESULTS

There was a uni-modal distribution of age, with most in the seventh decade (22%), followed by the sixth and eighth decades (19%). As a continuous variable, age was demonstrated to have an adverse effect on overall survival (OS, HR, 1.077, 95% CI 1.073-1.082, p = 0.000) and cancer-specific survival (CSS, HR, 1.099, 95% CI 1.092-1.106, p = 0.000) after adjusted proportional hazard analysis. Patients aged ≤ 60 years had significantly higher survival rates than those aged > 60 (5-year OS was 93% vs 64%, 10-year OS was 90% vs 45%, p = 0.000; 5-year CSS was 98% vs 80%, 10-year CSS 96% was 62%, p = 0.000). Similar survival trends were also observed in different sub-group analyses, including disease with different stages (p = 0.000), different histology subgroups (p = 0.000), and different sites (p = 0.000).

CONCLUSION

Age has an important effect on overall survival and cancer-specific survival. The addition of age to the primary site, histology, and stage improves predicting long-term outcomes in cutaneous B-cell lymphoma.

The Safety of Radiotherapy in the Treatment of Primary Cutaneous B-Cell Lymphoma: A Multidisciplinary Systematic Review

Primary cutaneous B-cell lymphomas (PCBCL) are rare types of extranodal non-Hodgkin's lymphoma. The choice of treatment usually depends on the variant of PCBCL, number, size, and location of the lesions, involved body surface area as well as patient's age and health condition. The efficacy of radiotherapy (RT) in the treatment of PCBCL has been widely reported conversely, data about the acute and late skin toxicity, patient's treatment satisfaction and quality of life are scarce. A systematic search using PubMed, Scopus, and Cochrane library was performed to identify full original articles analyzing the safety of RT in patients with PCBCL with the primary outcome to assess the acute and late skin toxicity. Secondary outcomes were complete remission, disease free survival, and overall survival. The literature search resulted in 276 articles including eight studies assessing the safety of RT for the treatment of PCBCL. Most patients (median 73%, range 11.9-99.9%) were recorded as having acute skin toxicity of grade 1-2, while acute grade 3-4 toxicity occurred in a median of 8% (range 4-23%) of patients. A median of 20% (range 4-54%) of patients had late skin toxicity of grade 1-2. No late grade 3-4 toxicity was reported. Only one study evaluated patient's satisfaction showing that the 97% of patients were satisfied with radiation therapy. This systematic review confirms the safety of RT in the treatment of PCBCL. Patients with a PCBCL should be managed in highly specialized centers in the context of a multidisciplinary team including dermatologist, hematologist, pathologist, and radiation oncologist.

De-escalated radiotherapy for indolent primary cutaneous B-cell lymphoma

OBJECTIVE

Radiotherapy (RT) has an established role in the curative treatment of indolent primary cutaneous B‑cell lymphoma (PCBCL). With the role of low-dose regimens such as 2 × 2 Gy being uncertain, we compared conventional-dose RT to a low-dose approach and investigated outcome and toxicities.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 26 patients with 44 cutaneous lesions treated at our institution between 2007 and 2017, comprising 22 marginal zone lymphoma (PCMZL) lesions and 22 follicle center lymphoma (PCFCL) lesions. Seven lesions (16%) were treated with low-dose RT (LDRT) (4 Gy) and 37 (84%) with conventional-dose RT (≥24 Gy, median 40 Gy). Median follow-up duration was 76 months.

RESULTS

The overall response rate (ORR) was 91% (complete response rate [CRR]: 75%). The 5‑year local control rate (LCR) was 88% and the 10-year LCR was 84%. The response rates were significantly higher following conventional-dose RT (ORR: 92% vs. 86%; CRR: 84% vs. 29%; P = 0.007). In terms of radiation dose, the rate of infield relapses (14% vs. 11%, P = 0.4) and the 5‑year LCR (86% vs. 90%, P = 0.4) were comparable in the LDRT and conventional-dose RT groups. During RT courses, about two-thirds of patients experienced mild toxicities, with grade I and II acute toxicity rates of 61% and 9%, respectively, with lower incidences of grade I (14% vs. 70%) and grade II (0% vs. 8%, P = 0.004) toxicities following LDRT.

CONCLUSION

This long-term analysis confirms the excellent outcome of RT in the management of PCBCL. The LDRT concept with 4 Gy was associated with a comparable LCR and reduced rates of acute toxicity. However, the response rates were significantly lower for this group and LDRT may therefore not be recommended as standard treatment.