Sjoerd Rodenhuis

K-ras Oncogene Activation as a Prognostic Marker in Adenocarcinoma of the Lung

BACKGROUND The capability of activated oncogenes to induce malignant transformation of immortalized cells in vitro has suggested that they have a similar role in the pathogenesis of human tumors. We previously found that activation of the K-ras oncogene by a point mutation in codon 12 occurs in about one third of human lung adenocarcinomas. METHODS We studied the clinical importance of this oncogene-activation in 69 patients with lung adenocarcinoma in whom complete resection of the tumor was possible. The polymerase chain reaction was used to amplify ras-specific sequences of DNA isolated from frozen or paraffin-embedded tumor samples. Ras point mutations were subsequently detected and classified with the use of mutation-specific oligonucleotide probes. RESULTS Nineteen of the tumors harbored a point mutation in codon 12 of the K-ras oncogene. There was no association between the K-ras point mutation and the age at diagnosis, sex, or presence of previous or concurrent neoplasms. Tumors positive for K-ras point mutations tended to be smaller and less differentiated than those without mutations. The K-ras codon-12 point mutation was a strong (and unfavorable) prognostic factor: 12 of the 19 patients with K-ras point-mutation-positive tumors died during the follow-up period, as compared with 16 of the 50 patients with no mutation in the K-ras oncogene (P = 0.002). This difference in prognosis was also reflected in the duration of disease-free survival (P = 0.038) and in the number of deaths due to cancer (P less than 0.001). CONCLUSIONS The presence of K-ras point mutations defines a subgroup of patients with lung adenocarcinoma in whom the prognosis is very poor and disease-free survival is not usually long despite radical resection and a small tumor load.

Clinical Pharmacokinetics of Cyclophosphamide

Cyclophosphamide is an extensively used anticancer and immunosuppressive agent. It is a prodrug undergoing a complicated process of metabolic activation and inactivation. Technical difficulties in the accurate determination of the cyclophosphamide metabolites have long hampered the assessment of the clinical pharmacology of this drug. As these techniques are becoming increasingly available, adequate description of the pharmacokinetics of cyclophosphamide and its metabolites has become possible.There is incomplete understanding on the role of cyclophosphamide metabolites in the efficacy and toxicity of cyclophosphamide therapy. However, relationships between toxicity (cardiotoxicity, veno-occlusive disease) and exposure to cyclophosphamide and its metabolites have been established. Variations in the balance between metabolic activation and inactivation of cyclophosphamide owing to autoinduction, dose escalation, drug-drug interactions and individual differences have been reported, suggesting possibilities for optimisation of cyclophosphamide therapy.Knowledge of the pharmacokinetics of cyclophosphamide, and possibly monitoring the pharmacokinetics of cyclophosphamide in individuals, may be useful for improving its therapeutic index.

Mutational activation of the K-ras oncogene. A possible pathogenetic factor in adenocarcinoma of the lung.

To define the role of cellular oncogenes in human cancers, we studied the prevalence of mutational activation of ras oncogenes in untreated non-small-cell lung cancer. Genomic DNA was extracted from 39 tumor specimens obtained by thoracotomy and was examined for activating point mutations in codons 12, 13, and 61 of the H-ras, K-ras, and N-ras genes. A novel, highly sensitive assay based on oligonucleotide hybridization following an in vitro amplification step was employed. The K-ras gene was found to be activated by point mutations in codon 12 in 5 of 10 adenocarcinomas. Two of these tumors were less than 2 cm in size and had not metastasized. No ras gene mutations were observed in 15 squamous-cell carcinomas, 10 large-cell carcinomas, 1 carcinoid, 2 metastatic adenocarcinomas from primary tumors outside the lung, and 1 small-cell carcinoma. An approximately 20-fold amplification of the unmutated K-ras gene was observed in a tumor that proved to be a solitary lung metastasis of a rectal carcinoma. We conclude that mutational K-ras activation may be an important early event in the pathogenesis of adenocarcinoma of the lung but that amplification of ras genes or mutational activation of H-ras or N-ras does not play a major part in non-small-cell lung cancer.

Phase II Study of ET-743 in Advanced Soft Tissue Sarcomas: A European Organisation for the Research and Treatment of Cancer (EORTC) Soft Tissue and Bone Sarcoma Group Trial

PURPOSE This nonrandomized multicenter phase II study was performed to evaluate the activity and safety of Ecteinascidin (ET-743) administered at a dose of 1.5 mg/m(2) as a 24-hour continuous infusion every 3 weeks in patients with pretreated advanced soft tissue sarcoma. PATIENTS AND METHODS Patients with documented progressive advanced soft tissue sarcoma received ET-743 as second- or third-line chemotherapy. Antitumor activity was evaluated every 6 weeks until progression, excessive toxicity, or patient refusal. RESULTS One hundred four patients from eight European institutions were included in the study (March 1999 to November 2000). A total of 410 cycles were administered in 99 assessable patients. Toxicity mainly involved reversible grade 3 to 4 asymptomatic elevation of transaminases in 40% of patients, and grade 3 to 4 neutropenia was observed in 52% of patients. There were eight partial responses (PR; objective regression rate, 8%), 45 no change (NC; > 6 months in 26% of patients), and 39 progressive disease. A progression arrest rate (PR + NC) of 56% was observed in leiomyosarcoma and 61% in synovialosarcoma. The median duration of the time to progression was 105 days, and the 6-month progression-free survival was 29%. The median duration of survival was 9.2 months. CONCLUSION ET-743 seems to be a promising active agent in advanced soft tissue sarcoma, with no cumulative toxicities. The 6-months progression-free survival observed in advanced soft tissue sarcoma compares favorably with those obtained with other active drugs tested in second-line chemotherapy in previous European Organisation for the Research and Treatment of Cancer trials. The median overall survival was unusually long in these heavily pretreated patients mainly due to the high number of patients who benefit from the drug in terms of tumor control.

Breast cancer response to neoadjuvant chemotherapy: predictive markers and relation with outcome

The aim of this study was to provide a better insight into breast cancer response to chemotherapy. Chemotherapy improves outcome in breast cancer patients. The effect of cytotoxic treatment cannot be predicted for individual patients. Therefore, the identification of tumour characteristics associated with tumour response and outcome is of great clinical interest. We studied 97 patients, who received anthracycline-based neoadjuvant chemotherapy. Tumour samples were taken prior to and after chemotherapy. We quantified the response to chemotherapy clinically and pathologically and determined histological and molecular tumour characteristics. We assessed changes in the expression of Bcl-2, ER, P53 HER2 and Ki-67. Association with response and outcome was tested for all parameters. The experimental results showed 15 clinical (17%) and three (3%) pathological complete remissions. There were 18 (20%) clinical vs 29 (33%) pathological nonresponders. The expression of most markers was similar before and after chemotherapy. Only Ki-67 was significantly decreased after chemotherapy. Factors correlated with response were: large tumour size, ER negativity, high Ki-67 count and positive P53 status. Tumour response and marker expression did not predict disease-free or overall survival. In conclusion, clinical and pathological response assessments are poorly associated. Proliferation decreases significantly after chemotherapy. ER negativity and a high proliferation index are associated with better response. HER2 status does not predict response, and outcome is not related to tumour response.

Randomised trial of high-dose chemotherapy and haemopoietic progenitor-cell support in operable breast cancer with extensive axillary lymph-node involvement

BACKGROUND Uncontrolled studies suggest that high-dose chemotherapy is beneficial in patients with breast cancer and multiple metastases to the axillary lymph nodes. Many physicians accept this treatment as standard care. We aimed to assess adjuvant high-dose chemotherapy in breast cancer in a phase II randomised trial. METHODS 97 women aged younger than 60 years, who had breast cancer with extensive axillary-node metastases (confirmed by a tumour-positive infraclavicular lymph-node biopsy), received three courses of up-front chemotherapy (FE120C). This regimen consisted of cyclophosphamide 500 mg/m2, epirubicin 120 mg/m2, and 5-fluorouracil 500 mg/m2 once weekly for 3 weeks. After surgery, stable patients or those who responded to chemotherapy were randomly assigned conventional therapy (fourth course of FE120C, followed by radiation therapy and 2 years of tamoxifen [40 patients]) or high-dose therapy (identical treatment but an additional high-dose regimen and peripheral-blood progenitor-cell [PBPC] support after the fourth FE120C course [41 patients]). This high-dose regimen comprised cyclophosphamide 6 g/m2, thiotepa 480 mg/m2, and carboplatin 1600 mg/m2. The primary endpoint was overall and disease-free survival. All analyses were by intention to treat. FINDINGS No patients died from toxic effects of chemotherapy. With a median follow-up of 49 (range 21-76) months, the 4-year overall and relapse-free survivals for all 97 patients were 75% and 54%, respectively. There was no significant difference in survival between the patients on conventional therapy and those on high-dose therapy. INTERPRETATION High-dose therapy is associated with substantial cost and acute toxic effects, but also has potentially irreversible long-term effects. Until the benefit of this therapy is substantiated by large-scale phase III trials, high-dose chemotherapy should not be used in the adjuvant treatment of breast cancer, apart from in randomised studies.

Randomized Phase III Study Comparing Conventional-Dose Doxorubicin Plus Ifosfamide Versus High-Dose Doxorubicin Plus Ifosfamide Plus Recombinant Human Granulocyte-Macrophage Colony-Stimulating Factor in Advanced Soft Tissue Sarcomas: A Trial of the European Organization for Research and Treatment of Cancer/Soft Tissue and Bone Sarcoma Group

PURPOSE This randomized multicenter study was designed to compare the activity of a high-dose doxorubicin-containing chemotherapy regimen with a conventional standard-dose regimen in adult patients with advanced soft tissue sarcomas (ASTS). PATIENTS AND METHODS Between 1992 and 1995, 314 patients were randomized to receive a standard-dose regimen (arm A), containing doxorubicin (50 mg/m(2) on day 1) and ifosfamide (5 g/m(2) on day 1), or an intensified regimen (arm B), combining doxorubicin (75 mg/m(2) on day 1), the same ifosfamide dose, and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; sargramostim, 250 microgram/m(2) on days 3 to 16); all courses were repeated every 3 weeks. RESULTS The median age of the 294 eligible patients was 50 years. They received a median of five chemotherapy cycles. The median dose and relative doxorubicin dose-intensity achieved were 245 mg and 97% in arm A and 360 mg and 99% in arm B, respectively. Thirty-eight percent and 23% of patients presented with leiomyosarcomas and liver metastases, respectively. Objective responses were observed in 31 (21%) of 147 assessable patients in arm A and in 31 (23.3%) of 133 in arm B (P =.65). No change was observed in 41.6% and 46.2% of patients in arm A and B, respectively. Progression-free survival (PFS) was significantly longer in the intensive arm (P =.03). The median duration of the time to progression was 19 weeks in the conventional arm and 29 weeks in the intensified arm. There was no difference in overall survival (P =.98) between the two therapeutic arms. Toxicities were manageable in both arms. A grade 3/4 neutropenia and infection occurred in 92% and 4.6% of patients in arm A, respectively, and in 90% and 16.6% in arm B, respectively. Grade 3/4 thrombocytopenia was more frequent in arm B. CONCLUSION The use of rhGM-CSF allowed safe escalation of chemotherapy doses. Despite a 50% increase of the doxorubicin dose-intensity, the high-dose regimen failed to demonstrate any impact on survival in patients with ASTS. The low complete response rate, the high incidence of leiomyosarcomas, and liver metastases may in part explain these results. However, the lengthening of the PFS in the intensive arm, because of the quality of stable disease and inappropriate tumor evaluation policies that potentially lead to an underestimation of antitumor activity, does not definitively refute the use of a high-dose chemotherapy regimen in selected patients with ASTS.

Magnetic Resonance Imaging Response Monitoring of Breast Cancer During Neoadjuvant Chemotherapy: Relevance of Breast Cancer Subtype

PURPOSE To evaluate the relevance of breast cancer subtypes for magnetic resonance imaging (MRI) markers for monitoring of therapy response during neoadjuvant chemotherapy (NAC). PATIENTS AND METHODS MRI examinations were performed in 188 women before and during NAC. MRI interpretation included lesion morphology at baseline, changes in morphology, size, and contrast uptake kinetics (initial and late enhancement). By using immunohistochemistry, tumors were divided into three subtypes: triple negative, human epidermal growth factor receptor 2 (HER2) positive, and estrogen receptor (ER) positive/HER2 negative. Tumor response was assessed dichotomously (ie, presence or absence of residual tumor in the surgical specimen). Complementary, a continuous scale assessment was used (the breast response index [BRI], representing the relative change in tumor stage). Multivariate regression analysis and receiver operating characteristic analysis were employed to establish significant associations. RESULTS Residual tumor at pathology was present in 31 (66%) of 47 triple-negative tumors, 23 (61%) of 38 HER2-positive tumors, and 96 (93%) of 103 ER-positive/HER2-negative tumors. Multivariate analysis of residual disease showed significant associations between breast cancer subtype and MRI (area under the curve [AUC], 0.84; P < .001). BRI also showed significant correlation among breast cancer subtype, MRI, and age (Pearsons r = 0.465; P < .001). In subset analysis, this was only significant for triple-negative tumors (P < .001) and HER2-positive tumors (P < .05). Residual tumor after NAC in the triple-negative and HER2-positive group is significantly associated with the change in largest diameter of late enhancement during NAC (AUC, 0.76; P < .001). No associations were found for ER-positive/HER2-negative tumors. CONCLUSION MRI during NAC to monitor response is effective in triple-negative or HER2-positive disease but is inaccurate in ER-positive/HER2-negative breast cancer.

Phase III Trial of Two Investigational Schedules of Ifosfamide Compared With Standard-Dose Doxorubicin in Advanced or Metastatic Soft Tissue Sarcoma: A European Organisation for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group Study

PURPOSE Single-agent doxorubicin remains the standard treatment for advanced soft tissue sarcomas. Combining doxorubicin with standard-dose ifosfamide has not been shown to improve survival and is associated with a significantly increased toxicity; it is not known whether higher dose single-agent ifosfamide is superior to doxorubicin. PATIENTS AND METHODS This randomized prospective multicenter phase III trial was designed to compare progression-free survival of patients with advanced soft tissue sarcoma receiving either regimen of standard doxorubicin 75 mg/m2 every 21 days, ifosfamide 9 g/m2 over 3 days continuous infusion, or ifosfamide 3 g/m2 per day in 3 hours over 3 days. The primary end point was progression-free survival. Secondary end points included overall survival, response rate, and toxicity. RESULTS The study included 326 patients. Grade 4 leukopenia, neutropenia, febrile neutropenia, and encephalopathy were more frequent in the ifosfamide arms. Progression-free survival, overall survival, and response rates were not significantly different between the three arms. An independent data monitoring committee reviewed the interim data and recommended early closure of the trial for futility (ie, no significant difference would be shown). CONCLUSION Single-agent doxorubicin remains the treatment of choice for patients with advanced soft tissue sarcoma.

Changes in Gene Expression Associated With Response to Neoadjuvant Chemotherapy in Breast Cancer

PURPOSE At present, clinically useful markers predicting response of primary breast carcinomas to either doxorubicin-cyclophosphamide (AC) or doxorubicin-docetaxel (AD) are lacking. We investigated whether gene expression profiles of the primary tumor could be used to predict treatment response to either of those chemotherapy regimens. PATIENTS AND METHODS Within a single-institution, randomized, phase II trial, patients with locally advanced breast cancer received six courses of either AC (n = 24) or AD (n = 24) neoadjuvant chemotherapy. Gene expression profiles were generated from core-needle biopsies obtained before treatment and correlated with the response of the primary tumor to the chemotherapy administered. Additionally, pretreatment gene expression profiles were compared with those in tumors remaining after chemotherapy. RESULTS Ten (20%) of 48 patients showed a (near) pathologic complete remission of the primary tumor after treatment. No gene expression pattern correlating with response could be identified for all patients or for the AC or AD groups separately. The comparison of the pretreatment biopsy and the tumor excised after chemotherapy revealed differences in gene expression in tumors that showed a partial remission but not in tumors that did not respond to chemotherapy. CONCLUSION No gene expression profile predicting the response of primary breast carcinomas to AC- or AD-based neoadjuvant chemotherapy could be detected in this interim analysis. More subtle differences in gene expression are likely to be present but can only be reliably identified by studying a larger group of patients. Response of a breast tumor to neoadjuvant chemotherapy results in alterations in gene expression.