Abstract
Metastatic calcification is characterized by abnormal deposition of calcium in extraosseous tissues resulting from disruption of calcium-phosphorus homeostasis. It occurs without tissue damage and is usually seen in normal organs. It is most commonly observed in patients with chronic renal failure, paraneoplastic hypercalcemia, and vitamin D intoxication. Metabolic superscan is characterized by diffusely increased skeletal activity with suppressed renal visualization, often without soft-tissue involvement. This pattern reflects altered radiotracer biodistribution secondary to severe metabolic bone turnover. We report a case of multiple myeloma in which diffuse 99mTc-MDP uptake was observed in the stomach on a metabolic superscan.
Keywords: Multiple myeloma, metabolic superscan, gastric uptake, hypercalcemia, methylene diphosphonate, bone scan
,


In the present case, diffuse gastric 99mTc-MDP uptake was observed in association with severe hypercalcemia and a metabolic superscan pattern in a patient with newly diagnosed multiple myeloma. Radionuclide bone scans are not routinely recommended in multiple myeloma since the disease usually progresses with osteolytic lesions (). The disease is characterized by systemic amyloid deposits or hypercalcemia; cases of extraosseous tracer uptake have rarely been reported, including gastric uptake (,,,). Kanoh et al. () performed gastric biopsies in a patient with myeloma who demonstrated amyloid deposits, and hypothesized that this was the cause of the observed activity. In our case, amyloid staining of the gastric mucosa was negative. Cases showing gastric uptake have been reported in the literature; however, the unique feature of our case was diffuse gastric involvement occurring concomitantly with a metabolic superscan, which has not been observed in other cases (,).
Footnotes
Ethics
Informed Consent: Written informed consent for the anonymized publication of clinical data and images was obtained from the patient prior to the initiation of the study.
Authorship Contributions
Surgical and Medical Practices: G.B.B., Ö.Ş., G.B., H.A., F.T., Concept: G.B.B., G.B., E.B., Design: G.B.B., H.A., E.B., Data Collection or Processing: G.B.B., H.A., E.B., Analysis or Interpretation: Ö.Ş., H.A., Literature Search: G.B.B., F.T., Writing: G.B.B., Ö.Ş., F.T., E.B.
Conflict of Interest: No conflicts of interest were declared by the authors.
Financial Disclosure: The authors declare that this study has received no financial support.
References
Wang Y, Xu Q, Li Y, Su Y, Wang L, Wang X, Ge J, Jing H, Guo Y, Chen Y, Li X, Zhuang JL, Tan J, Wang X, Zhong L, Luo J, Zhao P, Fan S, Ren J, Yang H, Mei H, Sun C, Li C, Sun X, Lu X, Gao G, Zhou Z, Pan Y, Sun Y, Hong Z, Liu Z, Ma Y, Wang Y, Sun W, Hou J, Mi J, Chen W, Huang X, Li B, Fu R, Shi J, Ran X, Zhou F, He A, Mao M, Cai Z, Li N, Xu M, Yan X, Yang W, An G, Gong L, Sun L, Li Z, Liu T, He Y, Yin J, Liu Y, Liu W, Bao L. Expert consensus on a multidisciplinary approach for the management of multiple myeloma-related bone disease. Cancer Pathog Ther. 2024;18:280-292.
Mir KB, Fatima S, Batool S, Marwat N, Faheem M, Ammar A. Extraosseous soft tissue uptake in multiple myeloma. J Pak Med Assoc. 2022;72:1454-1455.
Sood A, Seam RK, Sethi S, Gupta M. Diffuse hepatic and splenic Tc-99m MDP tracer uptake in case of multiple myeloma. Indian J Nucl Med. 2010;25:70-72.
Sasaki T, Okizaki A, Takahashi K, Mineta M, Nagasawa K, Fujimoto Y, Kohda K, Aburano T. Absent skeletal uptake of (99m)Tc-hydroxymethylene diphosphonate in the presence of AL-type amyloidosis associated with multiple myeloma. Jpn J Radiol. 2011;29:595-597.
Valdez VA, Jacobstein JG, Perlmutter S, Brusman H. Metastatic calcification in lungs and stomach demonstrated on bone scan in multiple myeloma. Clin Nucl Med. 1979;4:120-121.
Kanoh T, Uchino H, Yamamoto I, Torizuka K. Soft-tissue uptake of technetium-99m MDP in multiple myeloma. Clin Nucl Med. 1986;11:878-879.
Foley K, Mrcp PF. Marked gastric uptake of Tc-99m methylene diphosphonate (MDP) in a patient with myeloma and hypercalcemia. Radiol Case Rep. 2015;7:659.
Hirose Y, Tachibana J, Sugai S, Konda S, Hayabe T, Konishi F. Metastatic calcification in the stomach demonstrated by a bone scan in Bence Jones lambda myeloma. Jpn J Med. 1987;26:72-75.


