title: Predicting chemotherapeutic response to small-cell lung cancer of platinum compounds by thallium-201 single-photon emission computerized tomography.
abstract: Thallium-201 single-photon emission computerized tomography (SPECT) was used to clarify the relationship between 201Tl uptake and the response in chemotherapy to platinum compounds in 21 patients with small-cell lung cancer. 201Tl-SPECT scans were obtained twice: at 15 min (early scan) and 120 min (delayed scan) after an intravenous injection of 111 MBq (3 mCi) of thallium-201 chloride. We obtained the uptake ratio from each scan and calculated the retention index:uptake ratio = region of interest uptake/contralateral normal lung uptake; retention index = (delayed ratio - early ratio)/early ratio. After 201Tl scintigraphy, 12 patients received chemotherapy consisting of platinum compounds and nine were treated with chemoradiation. Among patients receiving only chemotherapy, the retention index correlated with the responses to chemotherapy. In an in vitro study, ouabain, an inhibitor of the Na,K-ATPase pump, reduced sensitivity to cisplatin and inhibited intracellular thallium uptake in the small-cell lung cancer cell line. These studies suggest that 201Tl-SPECT is a useful indicator of response to chemotherapy with platinum compounds in small-cell lung cancer, and that Na,K-ATPase is commonly involved in transporting both thallium and platinum compounds into cancer cells.
authors.affiliation: First Department of Medicine, School of Medicine, Hokkaido University, Nishi, Sapporo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tokuchi
authors.forename: H
authors.initials: H
authors.lastname: Isobe
authors.forename: H
authors.initials: H
authors.lastname: Takekawa
authors.forename: T
authors.initials: T
authors.lastname: Hanada
authors.forename: T
authors.initials: T
authors.lastname: Ishida
authors.forename: S
authors.initials: S
authors.lastname: Ogura
authors.forename: K
authors.initials: K
authors.lastname: Itoh
authors.forename: M
authors.initials: M
authors.lastname: Furudate
authors.forename: K
authors.initials: K
authors.lastname: Saito
authors.forename: Y
authors.initials: Y
authors.lastname: Kawakami
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology / Q000627:therapeutic use*; D016190:Carboplatin / Q000494:pharmacology / Q000627:therapeutic use*; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000188:drug therapy; D002470:Cell Survival / Q000187:drug effects; D002945:Cisplatin / Q000494:pharmacology / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005047:Etoposide / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D010042:Ouabain / Q000494:pharmacology; D011379:Prognosis; D011859:Radiography; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000201:enzymology
chemical_list: D013794:Thallium Radioisotopes; D010042:Ouabain; D005047:Etoposide; D016190:Carboplatin; D000254:Sodium-Potassium-Exchanging ATPase; D002945:Cisplatin