{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T04:27:05Z","timestamp":1772252825091,"version":"3.50.1"},"reference-count":5,"publisher":"Wiley","issue":"12","license":[{"start":{"date-parts":[[2025,12,1]],"date-time":"2025-12-01T00:00:00Z","timestamp":1764547200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Respirology Case Reports"],"published-print":{"date-parts":[[2025,12]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>Tarlatamab, a DLL3\u2010targeting bispecific T\u2010cell engager, is an emerging option for previously treated small\u2010cell lung cancer (SCLC). Pseudoprogression with tarlatamab is poorly defined and can mimic drug\u2010induced pneumonitis. A 77\u2010year\u2010old man with extensive\u2010stage SCLC developed fever and hypoxia by Day 3 after the first 1\u2010mg dose, with rapid tumour enlargement and diffuse left\u2010lung infiltrates. High\u2010dose methylprednisolone and tocilizumab produced prompt clinical and radiographic improvement; follow\u2010up imaging showed resolution of infiltrates and tumour regression below baseline, consistent with pseudoprogression. This case suggests a reversible, lung\u2010predominant immune reaction with acute peritumoral infiltration likely driven by T cells. We propose the provisional term \u2018Immune Cell\u2010Associated Respiratory Syndrome (ICARS)\u2019. We speculate that baseline carcinomatous lymphangitis may predispose to ICARS. Recognising ICARS may prevent misdiagnosis and avoid premature discontinuation of effective therapy.<\/jats:p>","DOI":"10.1002\/rcr2.70425","type":"journal-article","created":{"date-parts":[[2025,12,2]],"date-time":"2025-12-02T03:21:18Z","timestamp":1764645678000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Early Pseudoprogression Mimicking Pneumonitis After Tarlatamab Therapy: A Case Suggestive of Immune Cell\u2010Associated Respiratory Syndrome (\n                    <scp>ICARS<\/scp>\n                    )"],"prefix":"10.1002","volume":"13","author":[{"given":"Natsumi","family":"Kushima","sequence":"first","affiliation":[{"name":"Department of Respiratory Medicine Fukuoka University Hospital  Fukuoka Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2212-0631","authenticated-orcid":false,"given":"Toyoshi","family":"Yanagihara","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine Fukuoka University Hospital  Fukuoka Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Takato","family":"Ikeda","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine Fukuoka University Hospital  Fukuoka Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Noriyuki","family":"Ebi","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine Fukuoka University Hospital  Fukuoka Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hiroyuki","family":"Inoue","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine Fukuoka University Hospital  Fukuoka Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1209-1272","authenticated-orcid":false,"given":"Masaki","family":"Fujita","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine Fukuoka University Hospital  Fukuoka Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2025,12]]},"reference":[{"key":"e_1_2_10_2_1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa2307980"},{"key":"e_1_2_10_3_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.intimp.2018.03.018"},{"key":"e_1_2_10_4_1","doi-asserted-by":"publisher","DOI":"10.1002\/rcr2.70319"},{"key":"e_1_2_10_5_1","doi-asserted-by":"publisher","DOI":"10.3324\/haematol.2023.284436"},{"key":"e_1_2_10_6_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41577\u2010021\u201000547\u20106"}],"container-title":["Respirology Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/rcr2.70425","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,28]],"date-time":"2025-12-28T19:24:42Z","timestamp":1766949882000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/rcr2.70425"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12]]},"references-count":5,"journal-issue":{"issue":"12","published-print":{"date-parts":[[2025,12]]}},"alternative-id":["10.1002\/rcr2.70425"],"URL":"https:\/\/doi.org\/10.1002\/rcr2.70425","archive":["Portico"],"relation":{},"ISSN":["2051-3380","2051-3380"],"issn-type":[{"value":"2051-3380","type":"print"},{"value":"2051-3380","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,12]]},"assertion":[{"value":"2025-11-05","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-11-11","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-12-01","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70425"}}