Non-secretory plasma cell myeloma lacking light chain expression
Non-secretory myeloma is a rare subtype of plasma cell myeloma.
The initial work-up used for diagnosing non-secretory myeloma is no different than the standard multiple myeloma. The diagnosis of non-secretory myeloma relies on presence of monoclonal plasma cells established by immunophenotyping. Lack of light chain expression in non-secretory myeloma poses a diagnostic challenge.
The addition of immunohistochemical stain for heavy chain and Cyclin D1 may aid in definitive diagnosis.
A high incidence (83%) of t(11;14) (q13;q32) is present in non-secretory myeloma; which can be detected by karyotyping or fluorescence in situ hybridization (FISH).
Due to the rarity of the disease; there is no enough data to support using different treatment regimen other than the standard multiple myeloma regimen.
Monitoring patients with non-secretory myeloma is challenging; since we can us serum or urine Ig level in detecting response to therapy.
List of References:
1. Bieber AK, Martires KJ, Driscoll MS, Grant-Kels JM, Pomeranz MK1, Stein JA. Nevi and pregnancy. J Am Acad Dermatol. 2016 Oct;75(4):661-666.
2. Chan MP, Chan MM, Tahan SR. Melanocytic nevi in pregnancy: histologic features and Ki-67 proliferation index. J Cutan Pathol. 2010 Aug;37(8):843-51.
3. Caron M. Grin, M.D., Department of Dermatology, MC 6230, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030, USA. Does pregnancy alter melanocytic nevi? J Cutan Pathol. 2001 Sep;28(8):389-92.
4. Driscoll MS, Grant-Kels JM. Nevi and melanoma in pregnancy. Dermatol Clin. 2006 Apr;24(2):199-204.
5. Piana S, Tagliavini E, Ragazzi M, Zanelli M, Zalaudek I, Ciarrocchi A, Valli R. Lymph node melanocytic nevi: pathogenesis and differential diagnoses, with special reference to p16 reactivity. Pathol Res Pract. 2015 May;211(5):381-8.