{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T00:13:40Z","timestamp":1788135220758,"version":"build-2803163510"},"reference-count":23,"publisher":"SAGE Publications","license":[{"start":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T00:00:00Z","timestamp":1782864000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T00:00:00Z","timestamp":1782864000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Clin Med Insights Case Rep"],"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:p>Extramedullary plasmacytomas are an uncommon manifestation of multiple myeloma (MM) and may involve a wide range of soft-tissue sites. Superficial involvement of the back is particularly rare and may be mistaken for benign soft-tissue lesions. We report the case of a 59-year-old man with MM diagnosed in April 2024 who was treated with four cycles of bortezomib, cyclophosphamide, and dexamethasone (VCD), achieving remission with disappearance of serum and urine M-protein on immunofixation. In October 2025, the disease relapsed, with early progression despite treatment with daratumumab, prompting initiation of teclistamab therapy. During the course of his disease, he developed two progressively enlarging, painless indurations over the left upper and lower back. Ultrasound demonstrated well-circumscribed heterogeneous hypoechoic subcutaneous masses with internal arterial vascularity on Doppler imaging. Ultrasound-guided core biopsy revealed diffuse infiltration by monoclonal plasma cells expressing CD138 with lambda light-chain restriction, confirming secondary extramedullary plasmacytoma. This case highlights the importance of considering extramedullary plasmacytoma in the differential diagnosis of new superficial soft-tissue masses in patients with MM and underscores the complementary role of ultrasound and histopathological examination in establishing the diagnosis.<\/jats:p>","DOI":"10.1177\/11795476261485712","type":"journal-article","created":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T20:45:38Z","timestamp":1787949938000},"update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":0,"title":["Plasmacytomas in Extramedullary Manifestation of Multiple Myeloma: A Case Report"],"prefix":"10.1177","volume":"19","author":[{"given":"Jawad","family":"Hmayed","sequence":"first","affiliation":[{"name":"University of Balamand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4917-5272","authenticated-orcid":false,"given":"Doha","family":"Fadel","sequence":"additional","affiliation":[{"name":"University of Balamand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anthony","family":"Albayeh","sequence":"additional","affiliation":[{"name":"University of Balamand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chris","family":"Jreij","sequence":"additional","affiliation":[{"name":"University of Balamand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-1914-320X","authenticated-orcid":false,"given":"Karam","family":"Karam","sequence":"additional","affiliation":[{"name":"University of Balamand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lamita","family":"El Sett","sequence":"additional","affiliation":[{"name":"University of Balamand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charbel","family":"Fares","sequence":"additional","affiliation":[{"name":"University of Balamand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2026,8,28]]},"reference":[{"key":"e_1_3_5_2_2","volume-title":"The MD Anderson Manual of Medical Oncology","author":"Lin P","year":"2022","unstructured":"Lin P, Kaufman GP, Lee HC, et al. Multiple myeloma. In: Kantarjian HM, Wolff RA, Rieber AG, eds. The MD Anderson Manual of Medical Oncology. 4th ed. McGraw Hill Education; 2022. Available from. https:\/\/accessmedicine-mhmedical-com.uobezsecureaccess.idm.oclc.org\/content.aspx?bookid=3151&sectionid=264036759","edition":"4"},{"key":"e_1_3_5_3_2","doi-asserted-by":"publisher","DOI":"10.1111\/bjh.17338"},{"key":"e_1_3_5_4_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41408-022-00643-3"},{"key":"e_1_3_5_5_2","doi-asserted-by":"publisher","DOI":"10.11152\/mu-4503"},{"key":"e_1_3_5_6_2","volume-title":"StatPearls. Treasure Island (FL)","author":"Iqbal QUA","year":"2022","unstructured":"Iqbal QUA, Majid HJ. Plasmacytoma. In: StatPearls. Treasure Island (FL). StatPearls Publishing; 2022. Available from: https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK573076\/"},{"key":"e_1_3_5_7_2","first-page":"433","article-title":"Weitere Untersuchungen \u00fcber die K\u00f6rnelungen der Plasmazellen","volume":"16","author":"Schridde H","year":"1905","unstructured":"Schridde H. Weitere Untersuchungen \u00fcber die K\u00f6rnelungen der Plasmazellen. Centralblatt f\u00fcr Allgemeine Pathologie und Pathologische Anatomie. 1905;16:433-436.","journal-title":"Centralblatt f\u00fcr Allgemeine Pathologie und Pathologische Anatomie"},{"key":"e_1_3_5_8_2","doi-asserted-by":"publisher","DOI":"10.3389\/fonc.2022.1052903"},{"key":"e_1_3_5_9_2","doi-asserted-by":"publisher","DOI":"10.1002\/cam4.4816"},{"key":"e_1_3_5_10_2","doi-asserted-by":"publisher","DOI":"10.3390\/curroncol32030182"},{"key":"e_1_3_5_11_2","article-title":"Solitary plasmacytoma: Practice essentials, pathophysiology, etiology","author":"Fanning SR","year":"2024","unstructured":"Fanning SR. Solitary plasmacytoma: Practice essentials, pathophysiology, etiology. Medscape. 2024. Available from: https:\/\/emedicine.medscape.com\/article\/207233-overview","journal-title":"Medscape"},{"key":"e_1_3_5_12_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41375-019-0660-0"},{"key":"e_1_3_5_13_2","doi-asserted-by":"publisher","DOI":"10.3390\/diagnostics14161788"},{"key":"e_1_3_5_14_2","doi-asserted-by":"publisher","DOI":"10.1053\/j.sult.2020.08.019"},{"key":"e_1_3_5_15_2","doi-asserted-by":"publisher","DOI":"10.15557\/jou.2025.0015"},{"issue":"3","key":"e_1_3_5_16_2","first-page":"207","article-title":"The radiopathologic correlation of breast plasmacytoma","volume":"32","author":"Jang M","year":"2013","unstructured":"Jang M, Bae Y, Yun B, et al. The radiopathologic correlation of breast plasmacytoma. Journal of Korean Society of Medical Ultrasound. 2013;32(3):207-214. Available from: https:\/\/www.e-ultrasonography.org\/upload\/jksmu-32-3-207.pdf","journal-title":"Journal of Korean Society of Medical Ultrasound"},{"issue":"8","key":"e_1_3_5_17_2","first-page":"987","article-title":"A case of extramedullary plasmacytoma of the mesenteric lymph nodes. Rinsho Hoshasen","volume":"35","author":"Nishikawa H","year":"1990","unstructured":"Nishikawa H, Tanaka R, Nakada T, et al. A case of extramedullary plasmacytoma of the mesenteric lymph nodes. Rinsho Hoshasen. Clinical Radiography. 1990;35(8):987-990. PMID:2214230.","journal-title":"Clinical Radiography"},{"key":"e_1_3_5_18_2","doi-asserted-by":"publisher","DOI":"10.3324\/haematol.2013.094409"},{"key":"e_1_3_5_19_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.leukres.2011.09.017"},{"key":"e_1_3_5_20_2","doi-asserted-by":"publisher","DOI":"10.21147\/j.issn.1000-9604.2017.05.08"},{"key":"e_1_3_5_21_2","doi-asserted-by":"publisher","DOI":"10.1155\/2010\/307902"},{"key":"e_1_3_5_22_2","doi-asserted-by":"publisher","DOI":"10.1155\/2017\/9159035"},{"key":"e_1_3_5_23_2","doi-asserted-by":"publisher","DOI":"10.1186\/s41824-021-00100-7"},{"key":"e_1_3_5_24_2","doi-asserted-by":"publisher","DOI":"10.1002\/ccr3.5084"}],"container-title":["Clinical Medicine Insights: Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/11795476261485712","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/11795476261485712","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/11795476261485712","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,30]],"date-time":"2026-08-30T23:18:33Z","timestamp":1788131913000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/11795476261485712"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7]]},"references-count":23,"alternative-id":["10.1177\/11795476261485712"],"URL":"https:\/\/doi.org\/10.1177\/11795476261485712","relation":{},"ISSN":["1179-5476","1179-5476"],"issn-type":[{"value":"1179-5476","type":"print"},{"value":"1179-5476","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7]]},"article-number":"11795476261485712"}}