Danis Ryan, Regidor Bernard, Bujarski Sean, Jew Scott, Goldwater Marissa-Skye, Swift Regina, Eades Benjamin Mark, Emamy-Sadr Marsiye, Del Dosso Ashley, Berenson James
Berenson Cancer Center, West Hollywood, CA, USA.
Institute for Myeloma and Bone Cancer Research, West Hollywood, CA, USA.
Case Rep Oncol. 2024 Jul 12;17(1):747-752. doi: 10.1159/000539814. eCollection 2024 Jan-Dec.
Multiple myeloma (MM) is an incurable bone marrow (BM)-based cancer involving clonal plasma cells. Most patients show elevated levels of serum monoclonal protein (sMP) and kappa or lambda serum free light chains (sFLCs) at diagnosis. However, around 1-2% of patients, termed nonsecretory, do not produce these biomarkers. As the disease progresses, more patients may become unevaluable using conventional markers, requiring invasive and expensive procedures like BM biopsies and positron emission tomography-computed tomography (PET-CT) scans for assessment and highlighting the need for alternative methods to monitor disease progression.
We present a case report of an MM patient who developed nonsecretory disease during his second line of treatment when he complained of new rib pain; progressive disease was then confirmed on a PET-CT scan. The patient showed an increase in his serum B-cell maturation antigen (sBCMA) levels whereas his conventional myeloma markers did not detect disease activity (sMP remained undetectable and involved sFLC level was normal). After starting a new treatment regimen, his rib pain disappeared, PET-CT scan improved, and sBCMA levels decreased. Upon relapse, he developed increased rib pain with a rising sBCMA level; his conventional myeloma markers did not detect disease activity. After changing to a new regimen, his rib pain improved, and this was accompanied by a decrease in his sBCMA levels.
Thus, this case exemplifies the potential for sBCMA to provide a non-invasive method for monitoring MM patients who develop nonsecretory disease.
多发性骨髓瘤（MM）是一种无法治愈的基于骨髓（BM）的癌症，涉及克隆性浆细胞。大多数患者在诊断时血清单克隆蛋白（sMP）以及κ或λ血清游离轻链（sFLC）水平升高。然而，约1%-2%的患者，即所谓的非分泌型患者，不产生这些生物标志物。随着疾病进展，更多患者可能无法使用传统标志物进行评估，这就需要像骨髓活检和正电子发射断层扫描-计算机断层扫描（PET-CT）扫描这样的侵入性且昂贵的检查来进行评估，凸显了需要替代方法来监测疾病进展。
我们报告一例MM患者的病例，该患者在二线治疗期间出现非分泌型疾病，当时他主诉新出现的肋骨疼痛；随后PET-CT扫描证实疾病进展。患者血清B细胞成熟抗原（sBCMA）水平升高，而其传统骨髓瘤标志物未检测到疾病活动（sMP仍未检测到，受累sFLC水平正常）。开始新的治疗方案后，他的肋骨疼痛消失，PET-CT扫描结果改善，sBCMA水平下降。复发时，他肋骨疼痛加剧，sBCMA水平升高；其传统骨髓瘤标志物未检测到疾病活动。更换新方案后，他的肋骨疼痛改善，同时sBCMA水平下降。
因此，该病例证明了sBCMA有可能为监测发生非分泌型疾病的MM患者提供一种非侵入性方法。
