Monoclonal Gammopathy of Undetermined Significance with Metastatic Carcinoma – A Rare Presentation

Document Type: Case Reports


1 Dept. of Pathology, Pondicherry Institute of Medical Sciences, Pondicherry, India

2 Dept. of Biochemistry, Pondicherry Institute of Medical Sciences, Pondicherry, India

3 Dept. of Gastroenterology, Pondicherry Institute of Medical Sciences, Pondicherry, India


The presence of a low level of M protein in the peripheral blood <3gm/dl which is below the required cut off for the diagnosis of plasma cell myeloma is known as monoclonal gammopathy of undetermined significance (MGUS). Elevated levels of serum M protein and detection of M band on serum protein electrophoresis (SPE) can occur in chronic diseases not related to B cell disorders and not always diagnostic for B cell dyscrasias. It can also be seen in non hematological malignancies as seen in our case. We present a case of MGUS in a 59yr male patient, previously diagnosed and surgically treated for carcinoma prostate and colon. Serum electrophoresis revealed an M Band – monoclonal protein of 1.9 gm/dl. Urine for Bence Jones proteins was negative and his skeletal X-rays did not reveal lytic lesions.  Bone marrow aspiration revealed metastatic carcinoma. Plasma cells formed 1% of the bone marrow differential count.


  1. Kyle RA. Monoclonal gammopathy of undetermined significance. Natural history in 241 cases. Am J Med 1978 May;64(5):814-26.
  2. Swerdlow S, Campo E, Harris N, Jaffe E, Pileri S, Stein H. WHO Classification of  Tumors of Haematopoietic and Lymphoid Tissues. 4 ed. Lyon: IARC; 2008.
  3. Bida JP, Kyle RA, Therneau TM, Melton LJ, III, Plevak MF, Larson DR, et al. Disease associations with monoclonal gammopathy of undetermined significance: a population-based study of 17,398 patients. Mayo Clin Proc 2009 Aug;84(8):685-93.
  4. Kyle RA, Therneau TM, Rajkumar SV, Larson DR, Plevak MF, Melton LJ, III. Long-term follow-up of 241 patients with monoclonal gammopathy of undetermined significance: the original Mayo Clinic series 25 years later. Mayo Clin Proc 2004 Jul;79(7):859-66.
  5. Kyle RA, Rajkumar SV. Monoclonal gammopathy of undetermined significance. Br J Haematol 2006 Sep;134(6):573-89.
  6. Anagnostopoulos A, Galani E, Gika D, Sotou D, Evangelopoulou A, Dimopoulos MA. Monoclonal gammopathy of undetermined significance (MGUS) in patients with solid tumors: effects of chemotherapy on the monoclonal protein. Ann Hematol 2004 Oct;83(10):658-60.
  7. Gregersen H, Mellemkjaer L, Salling IJ, Sorensen HT, Olsen JH, Pedersen JO, et al. Cancer risk in patients with monoclonal gammopathy of undetermined significance. Am J Hematol 2000 Jan;63(1):1-6.
  8. Chen HP, Carroll JA. Monoclonal gammopathy in carcinoma of the colon. Am J Clin Pathol 1980 Apr;73(4):607-10.
  9. Chopra G, Gupta P, Mishra D. Evaluation of Suspected Monoclonal Gammopathies: Experience in a Tertiary Care Hospital. MJAFI 2006 Jun;(62):134-7.
  10. Bird J, Behrens J, Westin J, Turesson I, Drayson M, Beetham R, et al. UK Myeloma Forum (UKMF) and Nordic Myeloma Study Group (NMSG): guidelines for the investigation of newly detected M-proteins and the management of monoclonal gammopathy of undetermined significance (MGUS). Br J Haematol 2009 Oct;147(1):22-42.
  11. Hardiman KL, Horn S, Manoharan A, Phadke K, Gibson J, McGuigan L, et al. Rheumatic autoantibodies in the sera of patients with paraproteins. Clin Exp Rheumatol 1994 Jul;12(4):363-8.
  12. Idilman R, Colantoni A, De MN, Alkan S, Nand S, Van Thiel DH. Lymphoproliferative disorders in chronic hepatitis C. J Viral Hepat 2004 Jul;11(4):302-9.
  13. Malik AA, Ganti AK, Potti A, Levitt R, Hanley JF. Role of Helicobacter pylori infection in the incidence and clinical course of monoclonal gammopathy of undetermined significance. Am J Gastroenterol 2002 Jun;97(6):1371-4.
  14. Zent CS, Wilson CS, Tricot G, Jagannath S, Siegel D, Desikan KR, et al. Oligoclonal protein bands and Ig isotype switching in multiple myeloma treated with high-dose therapy and hematopoietic cell transplantation. Blood 1998 May 1;91(9):3518-23.
  15. Caforio AL, Gambino A, Belloni FA, Piaserico S, Scarpa E, Feltrin G, et al. Monoclonal gammopathy in heart transplantation: risk factor analysis and relevance of immunosuppressive load. Transplant Proc 2001 Feb;33(1-2):1583-4.
  16. Radl J, Valentijn RM, Haaijman JJ, Paul LC. Monoclonal gammapathies in patients undergoing immunosuppressive treatment after renal transplantation. Clin Immunol Immunopathol 1985 Oct;37(1):98-102.
  17. Renoult E, Bertrand F, Kessler M. Monoclonal gammopathies in HBsAg-positive patients with renal transplants. N Engl J Med 1988 May 5;318(18):1205.