Droplet-embedded Culture Drug Sensitivity Test Research Articles

Complete Response of a Patient with Advanced Primary Splenic Histiocytic Sarcoma by Treatment with Chemotherapeutic Drugs Selected Using the Collagen Gel Droplet-embedded Culture Drug Sensitivity Test

A 69-year-old man presented with multiple nodules on the spleen and liver that had been detected by computed tomography (CT). A liver tumor biopsy was performed, and the patient was diagnosed to have histiocytic sarcoma (HS). Splenectomy was performed, and the chemosensitivity of the spleen tumor was measured using the collagen gel droplet-embedded culture drug sensitivity test (CD-DST). Hepatic arterial infusion chemotherapy was administered, based on the results of the CD-DST. The patient achieved complete remission (CR) after this therapy and remained alive without recurrence at the final follow-up. This is the first known case of CR in response to chemotherapy for advanced splenic HS.

Success Rate of Collagen Gel Droplet-embedded Culture Drug Sensitivity Test in Colorectal Cancer: Are Antibiotics a Prerequisite for Specimen Irrigation?

The collagen gel droplet-embedded culture drug sensitivity test (CD-DST) is one of the best chemosensitivity tests owing to its high success rate. However, CD-DST is often a culture method, and contamination is a serious problem, especially in the case of colorectal cancer, which is contaminated by enteric bacteria. It has been reported that the success rate of CD-DST is 64.0% in the case of colorectal cancer. Therefore, the sampling and washing of specimens before culture are extremely important. By washing specimens carefully with normal saline containing antibiotics, we achieved a success rate of 85.3% in the case of colorectal cancer. To improve the success rate, we started specimen irrigation with a large amount of normal saline in January 2007. As a result, a success rate exceeding 90% was acquired. For the success of CD-DST for colorectal cancer, it is important to irrigate specimens many times with a large amount of normal saline.

Intrathoracic chemo-thermotherapy with radiofrequency waves after extrapleural pneumonectomy for malignant pleural mesothelioma

Although multimodal treatment is advocated for malignant pleural mesothelioma (MPM), a standard therapeutic regimen has not been established. This study evaluated the outcome of our aggressive treatment including extrapleural pneumonectomy (EPP) and postoperative intrathoracic chemo-thermotherapy (PICT). Moreover, we assessed the association between the clinical effect and an in vitro chemosensitivity test. Eleven patients with MPM underwent treatment including EPP followed by PICT using 8 MHz radiofrequency waves. In vitro chemosensitivity was examined using the collagen gel droplet embedded culture drug-sensitivity test (CD-DST). Complete resection was performed in nine patients. More than two courses of PICT with sufficient heating were completely performed in seven patients. There was no perioperative mortality. Grade 3 or 4 toxicity was not recognized. The median overall survival was 19 months, and the median local relapse-free survival was 17 months. Local recurrence was recognized in four patients (36.4%). Of these patients, three had received incomplete PICT. Four patients with complete PICT including a CD-DST-sensitive chemoagent did not develop local recurrence. Of three patients who received complete PICT including a CD-DST-resistant chemoagent, one tumor recurred locally. The present multimodal treatment including EPP and PICT is promising in local control for MPM. Furthermore, CD-DST may provide clinically useful information for MPM.

Chemosensitivity test for 5-fluorouracil and 5-chloro-2, 4-dihydroxypyridine predicts outcome of gastric cancer patients receiving S-1 postoperatively

Chemosensitivity tests have long been discussed but remain a topic of research. In this study, we investigated the correlation between the results of a chemosensitivity test for 5-fluorouracil and 5-chloro-2, 4-dihydroxypyridine and the clinical outcomes of gastric cancer patients treated with S-1, an oral fluoropyrimidine, as adjuvant chemotherapy. For gastric cancer patients, we performed surgical treatment and a lymph node dissection of D2 or more. Afterwards, a chemosensitivity test for 5-fluorouracil and 5-chloro-2, 4-dihydroxypyridine was performed, using the collagen gel droplet embedded culture drug-sensitivity test (CD-DST), in surgical specimens. All the patients received postoperative adjuvant chemotherapy with S-1 for 1 year, and the overall survival (OS), relapse-free survival (RFS), and adverse events were investigated. The chemosensitivity test was performed for 27 patients. The growth inhibition rate (IR) was 50% or more (high-sensitivity group) in 59.3% (16 cases) and it was under 50% (low-sensitivity group) in 40.7% (11 cases). The 3-year OS rate was 100% in the high-sensitivity group and 62.34% in the low-sensitivity group. The 3-year RFS rate was 83.33% in the high-sensitivity group and 24.24% in the low-sensitivity group. Thus, the 3-year OS rate and the 3-year RFS rate were higher in the high-sensitivity group than in the low-sensitivity group. No adverse events of grade 3 or greater severity were observed. The results of the chemosensitivity test were correlated with the patient outcome. Therefore, such results might be useful for individualizing cancer chemotherapy and for determining future indications for postoperative adjuvant chemotherapy.

Chemosensitivity of lung cancer: Differences between the primary lesion and lymph node metastasis

In this study, chemosensitivity tests were performed on both primary lesions (PLs) and lymph node metastases (LMs) from surgically resected non-small cell lung cancer (NSCLC). Differences between the results obtained were evaluated. Operative specimens were obtained from 13 patients with NSCLC [6 with squamous cell carcinoma (SQ) and 7 with adenocarcinoma (AD)] whose lymph nodes were confirmed to be positive for metastasis. Both the PL and LM from the same patient were examined immediately after resection. The collagen gel droplet-embedded culture drug sensitivity test (CD-DST) was used as the chemosensitivity test against six anticancer drugs [5-fluorouracil (5-FU), cisplatin, gemcitabine, docetaxel, vinorelbine and SN-38 (an active metabolite of irinotecan)]. When the growth rate, determined by the T/C ratio (T, signal for viable cells in the treated group and C, signal in the control) was less than 50%, the tumor cells were considered to be sensitive to the drug. Only in 4 cases (2 SQ and 2 AD) was the chemosensitivity of the primary lesion identical to that of LM. In the SQ cases, chemosensitivity of the primary lesions to 5-FU tended to be consistent with that of LMs. In contrast, the primary lesions in 4 of the 7 AD cases were negative for chemosensitivity to 5-FU; however, LMs were sensitive. In many cases, the chemosensitivity of the PLs to each anticancer drug differed from that of the LMs. In conclusion, both primary and metastatic tumors should be examined to ensure maximum clinical efficacy of in vitro drug-sensitivity testing for adjuvant chemotherapy after complete resection of n1 and n2 NSCLC.

Evaluation of the chemosensitivity of primary cultured malignant melanoma cells using the collagen gel droplet-embedded culture drug sensitivity test

Malignant melanoma usually shows resistance to a standard chemotherapy regimen. A useful in vitro method to evaluate individual chemosensitivity is required to select effective anti-cancer drugs. This study aimed to establish in vitro tumor response testing for malignant melanoma. We determined the chemosensitivity of primary cultured melanoma cells using the collagen gel droplet-embedded culture drug sensitivity test (CD-DST). Nineteen tests were carried out for 15 cases of malignant melanoma. Primary cultured melanoma cells in collagen gel droplets were exposed to anti-cancer drugs, including cisplatin, adriamycin, dacarbazine, nimustine and vincristine. After a 7-day incubation in a serum-free medium, living melanoma cells in a collagen droplet were detected by image analysis after staining with Neutral red reagent. In vitro drug exposure conditions were determined to reproduce the value of the plasma area under the time-drug concentration curve in vivo. The rate of evaluation of the primary culture of melanoma cells was 78.9% (15/19 tests). The chemosensitivity of cisplatin, adriamycin, dacarbazine, nimustine and vincristine was 15, 62, 0, 0 and 62%, respectively. Dacarbazine was not suitable for CD-DST due to its prodrug characteristics. The CD-DST method was able to evaluate the chemosensitivity of malignant melanoma to anti-cancer drugs in vitro. This method can also be applied to estimate the efficacy of newly developed anti-cancer drugs in vitro.

A Clinical Potential of the Anti-Cancer Drug Sensitivity Test for Patients with Endocrine Cell Carcinoma of the Rectum: Report of a Case

Endocrine cell carcinoma (ECC) of the rectum is a rare neoplasm usually associated with a poor prognosis. No standard chemotherapeutic regimens exist for the treatment of ECC. We encountered a case of rectal ECC in which chemotherapy was administered based on the results of a chemosensitivity test, the collagen gel droplet–embedded culture drug sensitivity test (CD–DST). A 64–year–old man with anal pain was diagnosed with rectal cancer. The patient received Mile's operation and was microscopically diagnosed as having ECC with foci of differentiation to adenocarcinoma. Multiple hepatic metastases were found 1 month after surgery. The patient received TEGAFIRI (oral UFT and leucovorin with irinotecan), which was intermediately sensitive based on the CD–DST. TEGAFIRI initially reduced the extent of hepatic metastases, indicating a partial response after 3 months of administration. However, progress of the disease was confirmed and TEGAFIRI had become ineffective after 5 months of administration. Thereafter, although mFOLFOX6 with bevacizumab, which was insensitive based on the CD–DST, was administered, the progression of hepatic metastases continued, indicating progressive disease. The patient died 13 months after surgery. In conclusion, we suggest that CD–DST may be useful for identifying sensitive antitumor agents for the treatment of rectal ECC for which no standard chemotherapeutic regimens exist.

Evaluation of the chemosensitivity of primary cultured malignant melanoma cells using the collagen gel droplet-embedded culture drug sensitivity test

Malignant melanoma usually shows resistance to a standard chemotherapy regimen. A useful in vitro method to evaluate individual chemosensitivity is required to select effective anti-cancer drugs. This study aimed to establish in vitro tumor response testing for malignant melanoma. We determined the chemosensitivity of primary cultured melanoma cells using the collagen gel droplet-embedded culture drug sensitivity test (CD-DST). Nineteen tests were carried out for 15 cases of malignant melanoma. Primary cultured melanoma cells in collagen gel droplets were exposed to anti-cancer drugs, including cisplatin, adriamycin, dacarbazine, nimustine and vincristine. After a 7-day incubation in a serum-free medium, living melanoma cells in a collagen droplet were detected by image analysis after staining with Neutral red reagent. In vitro drug exposure conditions were determined to reproduce the value of the plasma area under the time-drug concentration curve in vivo. The rate of evaluation of the primary culture of melanoma cells was 78.9% (15/19 tests). The chemosensitivity of cisplatin, adriamycin, dacarbazine, nimustine and vincristine was 15, 62, 0, 0 and 62%, respectively. Dacarbazine was not suitable for CD-DST due to its prodrug characteristics. The CD-DST method was able to evaluate the chemosensitivity of malignant melanoma to anti-cancer drugs in vitro. This method can also be applied to estimate the efficacy of newly developed anti-cancer drugs in vitro.

Establishing the method of collagen-gel droplet embedded culture drug sensitivity test with rat tail collagen

To explore the clinical application of collagen-gel droplet embedded-culture drug sensitivity test (CD-DST) in the malignant tumors. CD-DST was established with rat tail collagen. Three pancreatic cancer cell lines, surgical resection specimens including 15 cases of pancreatic cancer and 10 cases of gastrointestinal cancer were examined using CD-DST. The overall achievement ratio of CD-DST for clinical tumor specimens was 80% (20/25). In vitro chemosensitivities of pancreatic carcinoma cells to 5-FU, gemcitabine and oxaliplatin were lower than those of gastrointestinal carcinoma. CD-DST with rat tail collagen is a valuable chemosensitivity testing method for malignant tumors. It can be used to realize individualized anticancer chemotherapy.

Clinical potential of an antitumor drug sensitivity test and diffusion-weighted MRI in a patient with a recurrent solid pseudopapillary tumor of the pancreas

A solid pseudopapillary tumor (SPT) of the pancreas is a rare type of pancreatic neoplasm found predominantly in young women. SPTs typically behave as though benign; however, in some cases they also have malignant potential. We encountered a rare case of a recurrent SPT that developed 4 years after the initial surgery in an elderly male patient. Abdominal computed tomography (CT) revealed that the 61-year-old patient had four intra-abdominal masses, suggesting a recurrence of SPT. The patient had a history of distal pancreatectomy due to SPT in the pancreatic tail 4 years previously. These tumors showed positive signals on diffusion-weighted magnetic resonance imaging (MRI), and were treated successfully by aggressive surgical resection. Microscopic diagnosis was compatible with recurrent tumors of SPT. A chemosensitivity test, the collagen gel droplet-embedded culture drug sensitivity test (CD-DST), showed that the resected tumors were sensitive to several antitumor drugs. We suggest that the CD-DST may be used to indicate promising antitumor agents for treating SPTs with malignant tendencies. In addition, a diffusion-weighted MRI can be useful for accurately visualizing SPTs of the pancreas.

Collagen gel droplet-embedded culture drug-sensitivity test and potential for personalizing cancer treatment.

Sensitivity testing for general anticancer agents involves culturing cancer cells, exposure to an anticancer agent, and assessing the degree of growth inhibition. One such method is the collagen gel droplet-embedded culture drug-sensitivity test (CD-DST). Clinical results confirm a close correlation of a better than 75% accuracy between CD-DST results and responses to anticancer agents administered in the clinical setting. Although there have been few randomized, controlled studies of the CD-DST method, the general observation is that cancer patients survive longer if their disease responds to an anticancer agent than if it is ineffective. Therefore, it can be extrapolated that the high diagnostic accuracy of CD-DST is indirect evidence that this method can be used to select the group for whom chemotherapy will be effective, with a resultant prolongation of their survival time, and the group for whom chemotherapy will be ineffective, with no increased survival time.

A Case of Rectal Malignant Melanoma Showing Immunohistochemical Variability in a Tumor

We report on a patient with rectal malignant melanoma. The patient was a 40-year-old man who complained of anal bleeding. His grandmother had died of pancreatic cancer and his mother had been operated for rectal cancer. Physical examination revealed a hard mass at the 12 o'clock position, 2 cm from the anal verge. A colonoscopic examination revealed an irregular surface mass, approximately 4.0 cm in size, located on the anterior wall of the lower rectum. A biopsy of the rectal tumor showed the proliferation of epithelioid cells with pleomorphic features. Immunohistochemical analysis was performed. S-100 protein, CD-56, and KIT expression were positive, but HMB-45 expression was negative. Abdominopelvic computed tomography (CT) revealed multiple liver and lymph node metastases. With the diagnosis of neuroendocrine carcinoma of the rectum, abdominoperineal resection was performed. After the operation, the serum lactate dehydrogenase level had rapidly increased. An abdominal CT showed progressive liver metastases. Thirteen days after the surgery, abdominal angiography was performed, which showed multiple hypervascular tumor stains in the liver. The reservoir was implanted transcutaneously with the aid of angiography and the catheter was fixed to the proper hepatic artery. Neoadjuvant chemotherapy using cisplatin and irinotecan via the subcutaneous reservoir port was performed and a partial response was obtained. However, the final pathological diagnosis of the surgically resected specimen was malignant amelanotic melanoma of the rectum. Immunohistochemical expression differed between rectal biopsy specimens and surgically resected specimens. HMB-45 expression was positive and KIT expression was negative in the resected specimen. As preoperative pathological diagnosis showed rare rectal tumor, we measured the chemosensitivity of the rectal tumor using the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) to determine the most appropriate chemotherapy regimen for the patient. However, there were no anticancer drugs tested by CD-DST for malignant melanoma. With informed consent, the patient received two cycles of immunochemotherapy consisting of dacabazine, nimustine hydrochloride, vincristine sulfate, and interferon -beta. Although the patient was treated with immunochemotherapy for metastatic liver tumor, he died because of progression of metastases.

Prediction of cell kill kinetics of anticancer agents using the collagen gel droplet embedded-culture drug sensitivity test

A vital component of chemotherapy is selecting effective anticancer agents for the patient and determining an appropriate dose and administration regimen. Prediction of the drug sensitivity of each patient and cell kill kinetics of the drug may improve the outcome of treatment and avoid unnecessary dosing of the drug. For this reason, the development and clinical application of anticancer drug sensitivity tests and cell kill kinetics tests which successfully reflect clinical outcomes are required. In the present study, we tried to establish a cell kill kinetics test through the use of new anticancer agents: paclitaxel, docetaxel, SN-38, vinorelbine, and gemcitabine. These agents were studied at concentrations close to their clinical doses using a collagen gel droplet embedded-culture drug sensitivity test (CD-DST). It is thought that the mechanism, by which the anticancer agents used in this study exert their effects is dependent on the cell cycle; however, the cell kill kinetics of these agents at clinical concentrations has not yet been clarified in vitro. We investigated the drug sensitivity and cell kill kinetics of these new anticancer agents against a human colon cancer strain. Results of this study suggest that the test method established by us can predict drug sensitivity and cell kill kinetics of the agents, and can be a useful tool in deciding appropriate treatment regimen for individual patients.

Examination of in vitro Chemosensitivity Test Using Collagen Gel Droplet Culture Method with Colorimetric Endpoint Quantification

To develop a simpler method of performing the collagen gel droplet‐embedded culture drug sensitivity test (CD‐DST), we examined the introduction of colorimetric quantitative determination of images for evaluation of anticancer effect against cancer cells alone in the presence of fibroblasts, based on differences in proliferative morphology and stainability with neutral red of cells within collagen gel drops determined using a video‐microscope and NIH Image software. In examinations using a human cancer cell line and a fibroblast cell line, a high degree of linearity between number of cancer cells and image‐optical density was found within the range of 102–106 cells/droplet (r2=0.933). Using NIH Image, fibroblast cells could be eliminated at a cut‐off value of 128, and an immunocytochemical method demonstrated that the cells eliminated from the image were indeed fibroblasts, and those remaining were cancer cells. CD‐DST was carried out with mixtures of cancer cells with fibroblasts at various ratios, and the feasibility of evaluating anticancer activity in cancer cells alone with no effect of fibroblasts at any mixing ratio was confirmed. In addition, for CD‐DST of primary cell cultures of human lung cancers collected at the time of surgery, a high correlation between results obtained with the volume supplementation method, a current cell quantification method, and those with the imaging colorimetric quantification method was obtained (r=0.933). These results indicate that introduction of imaging colorimetric quantification utilizing NIH Image makes CD‐DST a quick and simple method that should be highly useful for clinical chemosensitivity testing using primary cell cultures of human cancers.