TY - JOUR
T1 - In vitro chemoresistance testing in well-differentiated carcinoid tumors
AU - Lyons, John M.
AU - Abergel, Jeffrey
AU - Thomson, Jessica L.
AU - Anthony, Cathy T.
AU - Wang, Yi Zarn
AU - Anthony, Lowell B.
AU - Boudreaux, J. Philip
AU - Strauchen, James
AU - Idrees, Muhammad
AU - Warner, Richard R.P.
AU - Woltering, Eugene A.
PY - 2009/3
Y1 - 2009/3
N2 - Background: Well-differentiated, "typical" carcinoid tumors traditionally have a very poor response to chemotherapy. We hypothesized that tumor specimens from well-differentiated carcinoid tumors would be highly resistant to the effects of chemotherapy when tested against a variety of antineoplastic agents in vitro. Methods: Ninety-eight typical carcinoid specimens were surgically harvested, cultured, and tested against antineoplastics in vitro. 3H-Thymidine incorporation was used to assess the percentage of cell-growth inhibition (PCI) of tested specimens. PCI was used to determine if specimens had extreme drug resistance (EDR), intermediate drug resistance (IDR), or low drug resistance (LDR) to each reagent against which they were tested. Results: Seventy specimens generated results. Each was tested with an average of six drugs. The mean proportions of drugs classified as LDR, IDR, and EDR were 0.48 (range 0-1), 0.34 (range 0-1), and 0.18 (range 0-0.80), respectively. The mean numbers of drugs per specimen exhibiting LDR, IDR, and EDR chemoresistance were 2.7, 2.1, and 1.2, respectively. 57 of 70 specimens (81%) had LDR to at least two drugs. 5-FU had the highest frequency of low chemoresistance at 69%, followed by doxorubicin at 67%. Low in vitro resistance to chemotherapeutics was prevalent among typical carcinoids, while EDR was comparatively infrequent. Conclusions: This implies that there may be less clinical chemoresistance and more chemosensitivity among typical carcinoid tumors than clinical trials have previously revealed. These findings warrant additional investigations assessing the response of carcinoid tumors to assay-guided chemotherapy regimens.
AB - Background: Well-differentiated, "typical" carcinoid tumors traditionally have a very poor response to chemotherapy. We hypothesized that tumor specimens from well-differentiated carcinoid tumors would be highly resistant to the effects of chemotherapy when tested against a variety of antineoplastic agents in vitro. Methods: Ninety-eight typical carcinoid specimens were surgically harvested, cultured, and tested against antineoplastics in vitro. 3H-Thymidine incorporation was used to assess the percentage of cell-growth inhibition (PCI) of tested specimens. PCI was used to determine if specimens had extreme drug resistance (EDR), intermediate drug resistance (IDR), or low drug resistance (LDR) to each reagent against which they were tested. Results: Seventy specimens generated results. Each was tested with an average of six drugs. The mean proportions of drugs classified as LDR, IDR, and EDR were 0.48 (range 0-1), 0.34 (range 0-1), and 0.18 (range 0-0.80), respectively. The mean numbers of drugs per specimen exhibiting LDR, IDR, and EDR chemoresistance were 2.7, 2.1, and 1.2, respectively. 57 of 70 specimens (81%) had LDR to at least two drugs. 5-FU had the highest frequency of low chemoresistance at 69%, followed by doxorubicin at 67%. Low in vitro resistance to chemotherapeutics was prevalent among typical carcinoids, while EDR was comparatively infrequent. Conclusions: This implies that there may be less clinical chemoresistance and more chemosensitivity among typical carcinoid tumors than clinical trials have previously revealed. These findings warrant additional investigations assessing the response of carcinoid tumors to assay-guided chemotherapy regimens.
UR - http://www.scopus.com/inward/record.url?scp=60449091225&partnerID=8YFLogxK
U2 - 10.1245/s10434-008-0261-z
DO - 10.1245/s10434-008-0261-z
M3 - Article
C2 - 19130141
AN - SCOPUS:60449091225
SN - 1068-9265
VL - 16
SP - 649
EP - 655
JO - Annals of Surgical Oncology
JF - Annals of Surgical Oncology
IS - 3
ER -