Multiple myeloma

Multiple myeloma

Epidemiology:

Multiple myeloma (MM) is a prominent hematological malignancy, accounting for approximately 1.8% of all new cancer cases in the United States, with about 34,920 diagnoses projected annually ¹. Despite advances in therapeutic approaches, including immunomodulatory agents and proteasome inhibitors, spontaneous remission (SR) remains exceedingly rare, representing less than 1% of documented cases in the context of MM ². SR occurrences in MM are often challenging to identify and report due to their low visibility in clinical practice and the subtle nature of the disease's progression, which can mask spontaneous remission events ³.

Clinical Characteristics:

To date, two cases of regression associated with multiple myeloma have been documented. These reports underscore the rarity of such observations and their occurrence in older adult patients aged between 59 and 82 years. Both cases involved primary disease originating in the bone marrow, with regression noted either systemically or at localized extramedullary sites, including complete resolution of a gastric lesion in one patient. See Table 1 for detailed case information.

Histological Characteristics:

Among the reviewed cases, the malignancy was restricted to bone marrow involvement, with regression occurring either as hematologic improvement or resolution of a localized gastric amyloid mass. These findings suggest a localized or disease-specific regression rather than systemic remission. No additional organ involvement or broader metastatic regression was reported, as only cases with clearly documented regression related to multiple myeloma were included.

Proposed Contributing Mechanisms:

Among the reported cases, the underlying mechanisms responsible for regression were not identified. The absence of proposed explanations limits insight into the biological or immunological processes that may have contributed. However, based on mechanisms described in related plasma cell disorders, immune-mediated effects, treatment-related modulation, or disease-specific cellular changes may represent plausible contributors to these uncommon regression events in multiple myeloma.

Site and Extent of Remission:

Both documented cases exhibited regression limited to the sites involved, with one showing hematologic improvement and the other complete resolution of a gastric amyloid mass. No additional organ regression or systemic remission was noted, indicating a localized response. Follow-up was limited, though one case demonstrated stability for 18 months. Overall, these findings suggest that regression in multiple myeloma, while rare, may manifest as site-specific clinical improvement rather than generalized disease reversal.

Table 1: Multiple myeloma SR Cases and Clinical Characteristics

References:

1. Al-Awadhi A, Leb L. Massive retroperitoneal hemorrhage as an initial presentation of a rare and aggressive form of multiple myeloma. Case Rep Hematol. 2016;2016:1-3. doi:10.1155/2016/8206826
2. Ria R, Vacca A, Mangialardi G, Dammacco F. Delayed complete remission in a patient with multiple myeloma. Eur J Clin Invest. 2008;38(12):966-968. doi:10.1111/j.1365-2362.2008.02049.x
3. Spontaneous sternal fracture in multiple myeloma: a case report. J Med Assoc Thai. 2023;106(8):820-823. doi:10.35755/jmedassocthai.2023.08.13882
4. Boyce NW, Holdsworth SR, Thomson NM, Atkins RC. “Long-term” survival in light-chain myeloma with dialysis therapy alone. Aust N Z J Med. 1984;14(5):676-677.
5. Bhagat G, Naiyer AJ, Green PH. Regression of a localized gastric amyloid mass in a patient treated for multiple myeloma. Gastrointest Endosc. 2009;69(4):950-951. doi:10.1016/j.gie.2008.10.050
6. Wolf et al., 1972. Remission of Macroglobulinemia Coincident with Hepatitis. Archives of Internal Medicine 120: 1972; 392-395
7. Arenas-Ruiz, J. A., Hernández-Álvarez, N., de Llano, J. P. N., Ponce-Ayala, A., & Nathal, E. (2021). Spontaneous regression of a thrombosed cerebral arteriovenous malformation in a patient with a prothrombotic state associated with multiple myeloma: A case report and literature review. Surgical neurology international, 12, 521. https://doi.org/10.25259/SNI_666_2021