Contributions
Abstract: EP1007
Type: E-Poster Presentation
Session title: Myeloma and other monoclonal gammopathies - Clinical
Background
Although protease inhibitors, immunomodulators, and hematopoietic stem cell transplantation prolong the survival of patients with multiple myeloma, the disease is still incurable. BCMA-CART treatment can make patients with relapsed and refractory multiple myeloma (RR MM) obtain Re-remission, but RR MM patients with extramedullary lesions are prone to relapse or progress again after BCMA-CART. Exploring the mechanism of relapse and progress in these patients is conducive to the selection of maintenance programs after CART to prolong survival.
Aims
The purpose of this study is to explore the disease characteristics of the disease progression of RR MM with extramedullary lesions after BCMA-CART treatment, so as to clarify the mechanism of recurrence or progression in this type of patients, and provide evidence for the selection of the maintenance plan for the patients who are in remission after the BCMA-CART treatment.
Methods
The clinical and molecular characteristics of patients with RR MM with extramedullary lesions who underwent BCMA-CART treatment in our hospital from January 2019 to December 2020 were collected, For disease remission, compare the flow cytometry and immunohistochemical changes of tumor tissue in patients with extramedullary lesions before BCMA-CART treatment and after recurrence or progression, and compare the molecular characteristics of patients with different prognosis to clarify the mechanism of disease recurrence or progression.
Results
From January 2019 to December 2020, a total of 8 patients with RR MM with extramedullary lesions were treated in our department. Of the 8 patients with extramedullary recurrence, 6 (75%) patients relapsed or progressed within 1 year after BCMA-CART treatment. The 6 patients with recurrence or progression had a curative effect assessment of 1 at 3 months after BCMA-CART treatment. 1 case (16.7%) CR, 4 cases (66.7%) PR, 1 case (16.7%) SD; 2 cases of patients who did not relapse and progressed within 1 year after BCMA-CART had CR (3 months after BCMA-CART). 100%). The recurrence or progression sites were bone marrow, cerebrospinal fluid, right psoas major and erector spinae muscles, right eyelid mass, right shoulder soft tissue and elevated serum M protein;
Before treatment, 8 patients underwent flow cytometry and immunohistochemical BCMA antigen detection of tumor tissues. The results showed that BCMA antigen expression was positive, and 4 of the 6 patients who relapsed or progressed were re-exposed to BCMA of tumor cells. Antigen detection of the first patient with bone marrow recurrence showed negative BCMA by bone marrow flow cytometry; the second patient with recurrence of right psoas major and erector spinae had negative tumor tissue flow BCMA, and immunohistochemistry showed weak BCMA positive; Three patients had new lesions on the right eyelid. The tumor tissue flow cytometry showed negative BCMA, and immunohistochemistry showed weak BCMA; the fifth patient had a progression of the right shoulder tumor, and the tissue flow cytometry showed negative BCMA, and puncture tumor immunity histochemistry was negative for BCMA.
Conclusion
In patients with RR MM with extramedullary lesions, the negative or weak expression of tumor cell surface antigens after BCMA-CART treatment may be one of the mechanisms of disease recurrence or progression; if not achieving deep remission 3 months after BCMA-CART treatment, the possibility of recurrence or progression after 1 year is high.
Key words:
RR MM with extramedullary lesions, BCMA-CART, extramedullary lesions
Keyword(s):
Abstract: EP1007
Type: E-Poster Presentation
Session title: Myeloma and other monoclonal gammopathies - Clinical
Background
Although protease inhibitors, immunomodulators, and hematopoietic stem cell transplantation prolong the survival of patients with multiple myeloma, the disease is still incurable. BCMA-CART treatment can make patients with relapsed and refractory multiple myeloma (RR MM) obtain Re-remission, but RR MM patients with extramedullary lesions are prone to relapse or progress again after BCMA-CART. Exploring the mechanism of relapse and progress in these patients is conducive to the selection of maintenance programs after CART to prolong survival.
Aims
The purpose of this study is to explore the disease characteristics of the disease progression of RR MM with extramedullary lesions after BCMA-CART treatment, so as to clarify the mechanism of recurrence or progression in this type of patients, and provide evidence for the selection of the maintenance plan for the patients who are in remission after the BCMA-CART treatment.
Methods
The clinical and molecular characteristics of patients with RR MM with extramedullary lesions who underwent BCMA-CART treatment in our hospital from January 2019 to December 2020 were collected, For disease remission, compare the flow cytometry and immunohistochemical changes of tumor tissue in patients with extramedullary lesions before BCMA-CART treatment and after recurrence or progression, and compare the molecular characteristics of patients with different prognosis to clarify the mechanism of disease recurrence or progression.
Results
From January 2019 to December 2020, a total of 8 patients with RR MM with extramedullary lesions were treated in our department. Of the 8 patients with extramedullary recurrence, 6 (75%) patients relapsed or progressed within 1 year after BCMA-CART treatment. The 6 patients with recurrence or progression had a curative effect assessment of 1 at 3 months after BCMA-CART treatment. 1 case (16.7%) CR, 4 cases (66.7%) PR, 1 case (16.7%) SD; 2 cases of patients who did not relapse and progressed within 1 year after BCMA-CART had CR (3 months after BCMA-CART). 100%). The recurrence or progression sites were bone marrow, cerebrospinal fluid, right psoas major and erector spinae muscles, right eyelid mass, right shoulder soft tissue and elevated serum M protein;
Before treatment, 8 patients underwent flow cytometry and immunohistochemical BCMA antigen detection of tumor tissues. The results showed that BCMA antigen expression was positive, and 4 of the 6 patients who relapsed or progressed were re-exposed to BCMA of tumor cells. Antigen detection of the first patient with bone marrow recurrence showed negative BCMA by bone marrow flow cytometry; the second patient with recurrence of right psoas major and erector spinae had negative tumor tissue flow BCMA, and immunohistochemistry showed weak BCMA positive; Three patients had new lesions on the right eyelid. The tumor tissue flow cytometry showed negative BCMA, and immunohistochemistry showed weak BCMA; the fifth patient had a progression of the right shoulder tumor, and the tissue flow cytometry showed negative BCMA, and puncture tumor immunity histochemistry was negative for BCMA.
Conclusion
In patients with RR MM with extramedullary lesions, the negative or weak expression of tumor cell surface antigens after BCMA-CART treatment may be one of the mechanisms of disease recurrence or progression; if not achieving deep remission 3 months after BCMA-CART treatment, the possibility of recurrence or progression after 1 year is high.
Key words:
RR MM with extramedullary lesions, BCMA-CART, extramedullary lesions
Keyword(s):