Prospective phase I trial of conservative management of low rectal lesions.

The purpose of this study was to assess and function and to compare the morbidity of local excision and postoperative radiotherapy for rectal adenocarcinoma with the morbidity of abdominoperineal resection. A posterior parasacral approach was used for local excision. All patients had negative margins, and all but one were continent after completion of radiotherapy. Seven patients (29%) had either a wound infection or a fistula in the local excision group. No local failures occurred, although follow-up was only 13 months. Thirteen (50%) of the 26 patients who underwent an abdominoperineal resection developed at least one complication. Combined treatment that spares the rectal sphincters may be preferable in selected patients with low rectal cancer, if long-term disease-free survival is maintained.

Drug and radiation sensitivity measurements of successful primary monolayer culturing of human tumor cells using cell-adhesive matrix and supplemented medium.

The limitations of the agar suspension culture method for primary culturing of human tumor cells prompted development of a monolayer system optimized for cell adhesion and growth. This method grew 83% of fresh human tumor cell biopsy specimens, cultured and not contaminated, from a heterogeneous group of 396 tumors including lung cancer (93 of 114, 82%); melanoma (54 of 72, 75%); sarcoma (46 of 59, 78%); breast cancer (35 of 39, 90%); ovarian cancer (16 of 21, 76%); and a miscellaneous group consisting of gastrointestinal, genitourinary, mesothelioma, and unknown primaries (78 of 91, 86%). Cell growth was characterized morphologically with Papanicolaoustained coverslip cultures and cytogenetically with Giemsastained metaphase spreads. Morphological features such as nuclear pleomorphism, chromatin condensation, basophilic cytoplasm, and melanin pigmentation were routinely seen. Aneuploid metaphases were seen in 90% of evaluable cultures, with 15 of 28 showing 70% or more aneuploid metaphases. Colony-forming efficiency ranged between 0.01 and 1% of viable tumor cells, with a median efficiency of 0.2%. This culture system uses a low inoculum of 25,000 viable cells per well which permitted chemosensitivity testing of nine drugs at four doses in duplicate from 2.2 X 10(6) viable tumor cells and radiation sensitivity testing at five doses in quadruplicate from 0.6 X 10(6) cells. Cultures were analyzed for survival by computerized image analysis of crystal violet-stained cells. Drug sensitivity studies showed variability in sensitivity and in survival curve shape with exponential cell killing for cisplatin, Adriamycin, and etoposide, and shouldered survival curves for 5-fluorouracil frequently seen. Radiation sensitivity studies also showed variability in both sensitivity and survival curve shape. Many cultures showed exponential cell killing, although others had shouldered survival curves. This method for growing cells from primary human biopsy specimens is more efficient than the agar culture method, enables easier and better biological analysis of the actual cells grown, and permits improved characterization of drug and radiation survival curves.

Activity of 2-fluoro-Ara AMP against gynecologic tumors in the soft agar assay.

To characterize in vitro activity of 2-fluoro-Ara AMP and its relation to the activities of cisplatin and doxorubicin, 28 specimens from patients wit gynecologic tumors (predominantly ovarian) were tested in a soft agar assay. Twenty-six of 28 (93%) grew when the medium was supplemented with four hormones (epidermal growth factor, hydrocortisone, estradiol-17, and insulin). Normal bone marrow cells were utilized as a biologic control to define in vitro concentrations of the three drugs. Tumors were exposed continuously to three different concentrations of each drug. 2-fluoro-Ara AMP was tested against 26 tumors, cisplatin against 24, and doxorubicin against 14. In vitro sensitivity was defined as greater than or equal to 50% colony inhibition at a drug concentration within the bone marrow inhibitory range. Seven of 26 (27%) tumor specimens were sensitive to 2-fluoro-Ara AMP. Among these, four tumors were derived from previously treated patients. However, in the 2-fluoro-Ara AMP concentration range (0.26 micrograms/ml to 0.78 micrograms/ml) tested, five of eight (62.5%) tumors from untreated patients achieved IC50 compared to only seven of 18 (39%) tumors from treated patients. Five of six (83%) specimens demonstrated cross-sensitivity between cisplatin and 2-fluoro-Ara AMP. Seventeen of 18 (94%) specimens demonstrated cross-resistance between cisplatin and 2-fluoro-Ara AMP, and 13 of 13 (100%) specimens demonstrated cross-resistance between 2-fluoro-Ara AMP and doxorubicin. A higher proportion of tumors from previously untreated patients achieved greater than or equal to 50% colony inhibition when exposed to 2-fluoro-Ara-AMP or cisplatin than did those from previously treated patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential cytotoxic activity of chemotherapy agents on colony-forming cells from human tumors and normal bone marrow in vitro.

We have compared the in vitro differential killing efficacy of doxorubicin, 5-fluorouracil, cis-platinum, etoposide, and bleomycin on human tumor cells in a new adhesive tumor cell culture system (ATCCS), and on normal bone marrow granulocyte-macrophage colony-forming units (GM-CFUC) in culture. All of the above chemotherapy agents were tested with continuous exposure against tumor cells and GM-CFUC. In addition, bleomycin was also tested with a short (60 min) exposure against GM-CFUC. In order to determine chemosensitivity against all five drugs, 48 tumor specimens from patients with heterogeneous tumor types were tested in the ATCCS. Each drug was tested at three different concentrations corresponding to their lethal doses against GM-CFUC. Our results show that all five drugs exhibited a dose-response relationship against tumor cells and GM-CFUC. Bleomycin also showed a pronounced GM-CFUC-sparing quality with 60-min exposure even at very high concentrations (86% survival of GM-CFUC at 10 micrograms/ml and 48% at 50 micrograms/ml). In addition, it has a high tumor response rate with continuous exposure at low concentrations (67% at GM-CFUC LD5 and 91% at LD40). These data suggest that the comparison of differential cytotoxicity of chemotherapy drugs between tumor cells and bone marrow cells may serve as a model to select agents suitable for in vitro chemotherapy of bone marrow for the purpose of autologous bone marrow transplantation. In particular, bleomycin appears very attractive and deserves further investigation.