Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2022

Exploring treatment options for primary cutaneous CD4+ small/ medium T-cell lymphoproliferative disorder (PCSMLPD) – with particular focus on ultra-low dose radiotherapy (#240)

Jennifer Ward 1 , H. Miles Prince 2 3 , Chris McCormack 4 5 , Stephen Lade 6 , Odette Buelens 2 , Carrie van der Wayden 2 , Friyana Bhabha 4 , Belinda Campbell 1 3 7
  1. Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
  2. Department of Haematology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
  3. The Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia
  4. Department of Surgical Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
  5. The Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia
  6. Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
  7. Department of Clinical Pathology, The University of Melbourne, Parkville, Victoria, Australia

Introduction

Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder (PCSMLPD) typically manifests as an indolent head/neck papule, frequently creating cosmetic concerns for patients. Optimal management is uncertain. Herein, we audit patient outcomes following 3 more commonly used management strategies: radiotherapy (RT), surgery and watchful-waiting. We also investigate the efficacy of ultra-low dose RT, which has not been previously studied in patients with PCSMLPD.

 

Methods

Eligibility required diagnosis of PCSMLPD, between 2007-2022, confirmed on central pathological review. RT responses were assessed: complete response (CR), less than CR, progressive disease (PD). Surgical excisions were classified: complete excision (CE) or incomplete excision (IE) using microscopic margins. Freedom from relapse (FFR) was compared between modalities.

 

Results

Of 41 eligible patients, 19 received RT first-line, 17 underwent excision (3 received adjuvant RT), and 5 chose watchful-waiting. Median follow-up was 37 (range, 6-167) months.

 

Overall, 24 patients received RT:  19 definitive first-line, 3 adjuvant first-line, 2 second-line. RT dose was 4Gy in 2 fractions in 10 (42%) patients, 20-40Gy in 14 (58%). Following RT, 100% achieved CR at 6 months, with no relapses. No toxicities were reported following 4Gy. 

 

Patients receiving surgery first-line (n=14, 3 with positive margins) had CE and IE rates of 65% and 35%, respectively. 4 (23.5%) patients experienced relapse (2 local, 2 distant) at median 12 (range, 6-36) months post-excision.

 

4 of 5 patients managed with watchful-waiting experienced partial resolution post-biopsy; no complete resolution observed.

 

3-year FFR was 100% for RT-alone vs 61% for surgery (p=0.12).

 

Conclusion

RT is a successful, non-invasive option for PCSMLPD with 100% CR rate, no relapses, and numerically superior FFR compared to surgery, in this cohort. Low-dose RT for PCSMLPD (4Gy in 2 fractions) offers durable control, no acute toxicities and convenient 2-day treatment time. For patients without cosmetic concerns, watchful-waiting is a reasonable management strategy.