**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Ellen Lewis, Tom Baker Cancer Centre

**Main Body of the Abstract**
Background: Treatment of amyloidosis is dependent on isolating the sub-type. Often, targeted biopsies are needed for sub-type confirmation, but the sensitivity of the chosen tissue biopsy site can vary. Transverse carpel ligament and tenosynovial biopsies from the wrist have recently become a high-yield site for obtaining an ATTR diagnosis; however, less is known for AL amyloidosis. We present a case of dual amyloidosis diagnosed via wrist biopsies.
Case Report: An 88-year-old male presented in 2023 with heart failure (NYHA class III; ECOG 3), NTProBNP 30000ng/ml, and PYP scan suggestive of ATTR amyloidosis (HCC ratio of 1.98; Grade 2). Fat pad biopsy negative. Too unwell for cardiac biopsy, wrist biopsies were obtained showing both ATTR and AL amyloidosis. Tafamidis was chosen to treat his ATTR amyloid and treatment for his AL amyloid included weekly Rituximab x4 weeks targetting B-cell clone followed by CyBorD-Daratumumab for light-chain reduction. After 1-month of Tafamidis and 1dose of Rituximab, he as hospitalized for deconditioning and Tafamidids was discontinued per his request. He tolerated the final doses of Rituximab and 1 cycle of CyBorD-Daratumumab. He attained a PR after the first cycle and, given his age, CyBorD was discontinued in favor of Daratumumab monotherapy. To date, he has attained a VGPR. He has improved functionally by walking 1-2km per day.
Conclusion: This is the first case of dual amyloidosis diagnosed in Canada and the first case of AL amyloidosis diagnosed via wrist biopsies at our Centre. Future research is needed on the approach to dual amyloiud treatment.



**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Ellen Lewis, Tom Baker Cancer Centre

**Main Body of the Abstract**
**Background:** Treatment of amyloidosis is dependent on isolating the sub-type. Often, targeted biopsies are needed for sub-type confirmation, but the sensitivity of the chosen tissue biopsy site can vary. Transverse carpel ligament and tenosynovial biopsies from the wrist have recently become a high-yield site for obtaining an ATTR diagnosis; however, less is known for AL amyloidosis. We present a case of dual amyloidosis diagnosed via wrist biopsies.
**Case Report:** An 88-year-old male presented in 2023 with heart failure (NYHA class III; ECOG 3), NTProBNP 30000ng/ml, and PYP scan suggestive of ATTR amyloidosis (HCC ratio of 1.98; Grade 2). Fat pad biopsy negative. Too unwell for cardiac biopsy, wrist biopsies were obtained showing both ATTR and AL amyloidosis. Tafamidis was chosen to treat his ATTR amyloid and treatment for his AL amyloid included weekly Rituximab x4 weeks targetting B-cell clone followed by CyBorD-Daratumumab for light-chain reduction. After 1-month of Tafamidis and 1dose of Rituximab, he as hospitalized for deconditioning and Tafamidids was discontinued per his request. He tolerated the final doses of Rituximab and 1 cycle of CyBorD-Daratumumab. He attained a PR after the first cycle and, given his age, CyBorD was discontinued in favor of Daratumumab monotherapy. To date, he has attained a VGPR. He has improved functionally by walking 1-2km per day.
**Conclusion:** This is the first case of dual amyloidosis diagnosed in Canada and the first case of AL amyloidosis diagnosed via wrist biopsies at our Centre. Future research is needed on the approach to dual amyloiud treatment.



Dual Amyloidosis Found on Transverse Carpel Ligament Biopsy: A Case Report  PC22 (#427)

We invite you to attend the XIX International Symposium on Amyloidosis to be held in Rochester, MN.

This symposium is organized as a hybrid meeting (with the focus on in-person) held from Sunday, May 26 through Thursday, May 30, 2024.

Together with the ISA Board and members of Mayo Clinic, a very attractive scientific hybrid program is being planned. The program will cover a variety of types of systemic amyloidosis: ATTR (hereditary and wild-type), AL (light-chain), AA and less frequent forms. There will be key lectures, specific symposia including those company sponsored, oral presentations and poster sessions of accepted abstracts.

COURSE DESCRIPTION
This program will provide a comprehensive review of state-of-the-art education in systemic amyloidosis: basic science, pathophysiology, diagnosis, current and emerging treatments. Scientific presentations will include competitive oral and poster abstracts. The rapid evolution of scientific discovery and expanding treatment options has created tremendous interest in the field and this meeting will fill and important gap in educating scientists and clinicians.