Dipyridamole modulated Tc-99m sestamibi lung SPECT in small cell lung cancer.
OBJECTIVE
In this study, the authors wanted to determine whether dipyridamole-modulated MIBI (dipyridamole-MIBI) could enhance the prediction of the response to chemotherapy in patients with small cell lung cancer.


METHODS
Twenty-seven patients with biopsy-proved small cell lung cancer (25 men, 2 women; mean age, 61 +/- 7 years) underwent dipyridamole-MIBI SPECT 3 to 7 days before starting chemotherapy (80 mg/m2 etoposide and 80 mg/m2 cisplatin every 3 or 4 weeks for at least two cycles). Tomographic images before and after dipyridamole (0.84 mg/kg) were acquired 1 hour after injection of 370 (10 mCi) and 1,110 (30 mCi) MBq MIBI, respectively. The response to chemotherapy was grouped as specified as complete response (CR), partial (PR), no change (NC), or progressive disease (PD), according to the change in tumor size on chest roentgenography and CT. Patients showing CR and PR were classified as responders, and those who showed NC and PD were considered nonresponders.


RESULTS
Among the 27 patients, 22 were responders (3 CR, 19 PR) and 5 were nonresponders (3 NC, 2 PD). The tumor-to-normal lung ratio (T:NL) of responders was significantly higher than that of nonresponders. The diagnostic accuracy of the T:NL ratio to differentiate responders and nonresponders was 33.3%, with a cutoff value of 2.5, which was significantly improved to 77.8% when an increased T:NL ratio after dipyridamole was assigned to a nonresponder. Furthermore, all patients with CR showed diminished T:NL ratios after dipyridamole, and all patients with NR showed an increased T:NL ratio after dipyridamole.


CONCLUSIONS
Dipyridamole-MIBI SPECT could enhance the prediction of response to chemotherapy in patients with small cell lung cancer.
Bom
H S
HS
Department of Nuclear Medicine, Chonnam University Hospital, Kwangju, Korea. hsbom@chonnam.ac.kr
Lim
S C
SC
Kim
Y C
YC
Song
H C
HC
Min
J J
JJ
Jeong
H J
HJ
Kim
J Y
JY
Lee
J
J
Park
K O
KO
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000032:analysis; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D018288:Carcinoma, Small Cell / Q000000981:diagnostic imaging* / Q000188:drug therapy; D002945:Cisplatin / Q000008:administration & dosage; D004176:Dipyridamole; D018432:Drug Resistance, Multiple; D005047:Etoposide / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008168:Lung / Q000737:chemistry; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon