Liver regenerative nodular hyperplasia consecutive to preoperative chemotherapy: Impact on outcome of liver surgery for colorectal metastases

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Background: Regenerative nodular hyperplasia (RNH) represents the worst evolutive stage of vascular lesions induced by prolonged chemotherapy on the liver. Its incidence and impact on the outcome of resection for colorectal liver metastases (CLM) are however unknown. We evaluated the effect of RNH on postoperative morbidity and assessed its evolution in time at repeat hepatectomy. Methods: All patients that underwent hepatectomy for CLM between January 1990 and November 2006 after 1 line of chemotherapy of more than 6 cycles were included. Detailed histopathologic analysis of the nontumoral liver was performed at first and repeat hepatectomies according to a standard format. Results: Of 146 included patients, 24 (16%) received 5- fluorouracil (5-FU) and leucovorin (LV) alone, 92 (63%) had 5-FU, LV and oxaliplatin, 18 (12%) had 5-FU, LV and irinotecan, and 12 (8%) were treated by 5-FU, LV, oxaliplatin and irinotecan. Overall, RNH occurred in 22 of 146 patients (15%). Patients treated by oxaliplatin more often had RNH compared to oxaliplatin-naïve patients (22% vs 4%) (P=0.003). The presence of RNH was associated with increased postoperative hepatic morbidity (23% vs 11%) (P=0.05). None of the RNH patients died within 60 days postoperatively. A preoperative gamma-glutamyltransferase level >80 U/L and a total bilirubin level >15 μmol/L were independent predictive factors of RNH at first hepatectomy. Two of 22 patients with RNH underwent repeat hepatectomy. RNH disappeared at second hepatectomy in both patients following prolonged treatment with irinotecan. Conclusions: Patients with CLM that receive prolonged courses of preoperative oxaliplatin have an increased risk of RNH and associated postoperative hepatic morbidity. Upfront treatment with short courses of highly effective regimens may therefore be most appropriate. In addition, the continuation of oxaliplatin should be discouraged in case of RNH to avoid its negative effects on further surgery.

No significant financial relationships to disclose.

Postoperative liver function recovery after hepatic resection for colorectal metastases previously treated with bevacizumab

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Background: The influence of bevacizumab on postoperative morbidity in patients with colorectal liver metastases (CLM) submitted to hepatectomy has been evaluated. However, in spite of a potential inhibition of liver regeneration, its impact on postoperative liver function recovery remains unknown. Methods: From July 2005 to December 2007, we evaluated 37 patients treated with bevacizumab prior to hepatectomy. Postoperative evolution of liver function variables was compared with that of 70 bevacizumab-naïve patients. Recorded parameters included prothrombin time, serum aspartate and alanine aminotransferase levels, and serum gamma-glutamyltransferase and total bilirubin levels. Results: Most patients of the bevacizumab group received 1 line of chemotherapy (62% vs 54% in the control group) (P=0.43). Bevacizumab was combined to 5-fluorouracil (5-FU), leucovorin (LV) and irinotecan or 5-FU, LV and oxaliplatin in the last preoperative line, in 57% and 30% of cases, respectively. Patients received a mean total number of 10.4+5.7 and 11.1+6.2 cycles of preoperative chemotherapy in the bevacizumab and control group (P=0.56). The median number of administered bevacizumab cycles was 6 (range: 3–25). Bevacizumab administration was stopped at a median of 7.9 weeks before surgery (range: 3.6–18.0). Major hepatectomies were performed in 41% and 36% of bevacizumab and control patients, respectively (P=0.62). Baseline liver function tests as well as postoperative liver function recovery were similar between patients treated with or without bevacizumab (Table). Postoperative morbidity occurred in 35% of bevacizumab patients and in 43% of control patients (P=0.44). Conclusions: Preoperative bevacizumab treatment has no impact on short-term liver function recovery after hepatic resection for CLM and has no deleterious effect on the incidence of postoperative morbidity.

[Table: see text]

No significant financial relationships to disclose.

Patients With Initially Unresectable Colorectal Liver Metastases: Is There a Possibility of Cure?

Purpose

Although oncosurgical strategies have demonstrated increased survival in patients with unresectable colorectal liver metastases (CLM), their potential for cure is still questioned. The aim of this study was to evaluate long-term outcome after combining downsizing chemotherapy and rescue surgery and to define prognostic factors of cure.

Patients and Methods

All patients with initially unresectable CLM who underwent rescue surgery and had a minimum follow-up of 5 years were included. Cure was defined as a disease-free interval ≥ 5 years from last hepatic or extrahepatic resection until last follow-up.

Results

Mean age of 184 patients who underwent resection (April 1988 through July 2002) was 56.9 years. Patients had a mean number of 5.3 metastases (bilobar in 76%), associated to extrahepatic disease in 27%. Surgery was possible after one (74%) or more (26%) lines of chemotherapy. Five- and 10-year overall survival rates were 33% and 27%, respectively. Of 148 patients with a follow-up ≥ 5 years, 24 patients (16%) were considered cured (mean follow-up, 118.6 months), six (25%) of whom were considered cured after repeat resection of recurrence. Twelve “cured” patients (50%) had a disease-free interval more than 10 years. Cured patients more often had three or fewer metastases less than 30 mm (P = .03) responding to first-line chemotherapy (P = .05). Multivariate analysis identified maximum size of metastases less than 30 mm at diagnosis, number of metastases at hepatectomy three or fewer, and complete pathologic response as independent predictors of cure.

Conclusion

Cure can be achieved overall in 16% of patients with initially unresectable CLM resected after downsizing chemotherapy. In addition to increased survival, this oncosurgical approach has real potential for disease eradication.

A randomized multicenter study of optimal circadian time of vinorelbine combined with chronomodulated 5-fluorouracil in pretreated metastatic breast cancer patients: EORTC trial 05971

Studies in animals synchronized with an alternation of 12 h of light and 12 h of darkness have showed that hematological and systemic toxicities could be reduced if vinorelbine were administered 19 or 23 hours after light onset (HALO), corresponding to 17:00 and 21:00 h in diurnally active humans. This trial aimed to define the least toxic time of vinorelbine administration in metastatic breast cancer patients. Initially, the study treatment consisted of three courses of vinorelbine of 30 mg/m(2)/d on D1 and D6 and chronomodulated 5-fluorouracil of 850 mg/m(2) from D2 to D5 every 21 days. Ninety metastatic breast cancer patients were randomized to receive vinorelbine at one of the eight possible dosing times. Further to the recommendations of the Independent Data Monitoring Committee, the vinorelbine dose was reduced to 25 mg/m(2)/d midway through the study. The primary objective of the study was detection of the least toxic time based on the incidence of grade 3-4 (G3-4) neutropenia. To show a significant result, the 90% confidence interval width of the least toxic time had to be<6 h. The least toxic time detection based on the incidence of other toxicities was also analyzed. The time of least drug toxic was estimated using a logistic regression model assuming that the logit transformation of the toxicity rate follows a sinusoidal distribution over 24 h. The bootstrap technique was used to obtain the 90% confidence interval. The least toxic time of G3-4 neutropenia was observed at 21:00 h with a non-significant 90% CI. Secondary endpoint analyses indicated the least toxic time could differ when based on other toxicity parameters (e.g., a significant least toxic time of 17:00 h was observed for G3-4 leucopenia), in agreement with animal data. The least toxic time of 10:30 h was estimated for any G3-4 gastrointestinal toxicity. This results of this study do not allow us to recommend an optimal time for vinorelbine administration. It has highlighted, however, the inherent methodological difficulties in the conduct of such a trial in the human setting. It indicates that future optimal time-finding trials should have tolerability and/or activity as the primary endpoint in place of a particular toxicity. The randomized optimal time-finding design may be used to identify the best time of chemotherapy administration.

Identifying mechanisms of chronotolerance and chronoefficacy for the anticancer drugs 5-fluorouracil and oxaliplatin by computational modeling

We use an automaton model for the cell cycle to assess the toxicity of various circadian patterns of anticancer drug delivery so as to enhance the efficiency of cancer chronotherapy. Based on the sequential transitions between the successive phases G1, S (DNA replication), G2, and M (mitosis) of the cell cycle, the model allows us to simulate the distribution of cell cycle phases as well as entrainment by the circadian clock. We use the model to evaluate circadian patterns of administration of two anticancer drugs, 5-fluorouracil (5-FU) and oxaliplatin (l-OHP). We first consider the case of 5-FU, which exerts its cytotoxic effects on cells in S phase. We compare various circadian patterns of drug administration differing by the time of maximum drug delivery. The model explains why minimum cytotoxicity is obtained when the time of peak delivery is close to 4a.m., which temporal pattern of drug administration is used clinically for 5-FU. We also determine how cytotoxicity is affected by the variability in duration of cell cycle phases and by cell cycle length in the presence or absence of entrainment by the circadian clock. The results indicate that the same temporal pattern of drug administration can have minimum cytotoxicity toward one cell population, e.g. of normal cells, and at the same time can display high cytotoxicity toward a second cell population, e.g. of tumour cells. Thus the model allows us to uncover factors that may contribute to improve simultaneously chronotolerance and chronoefficacy of anticancer drugs. We next consider the case of oxaliplatin, which, in contrast to 5-FU, kills cells in different phases of the cell cycle. We incorporate into the model the pharmacokinetics of plasma thiols and intracellular glutathione, which interfere with the action of the drug by forming with it inactive complexes. The model shows how circadian changes in l-OHP cytotoxicity may arise from circadian variations in the levels of plasma thiols and glutathione. Corroborating experimental and clinical results, the simulations of the model account for the observation that the temporal profiles minimizing l-OHP cytotoxicity are in antiphase with those minimizing cytotoxicity for 5-FU.

Implications of circadian clocks for the rhythmic delivery of cancer therapeutics

The circadian timing system (CTS) controls drug metabolism and cellular proliferation over the 24 hour day through molecular clocks in each cell. These cellular clocks are coordinated by a hypothalamic pacemaker, the suprachiasmatic nuclei, that generates or controls circadian physiology. The CTS plays a role in cancer processes and their treatments through the downregulation of malignant growth and the generation of large and predictable 24 hour changes in toxicity and efficacy of anti-cancer drugs. The tight interactions between circadian clocks, cell division cycle and pharmacology pathways have supported sinusoidal circadian-based delivery of cancer treatments. Such chronotherapeutics have been mostly implemented in patients with metastatic colorectal cancer, the second most common cause of death from cancer. Stochastic and deterministic models of the interactions between circadian clock, cell cycle and pharmacology confirmed the poor therapeutic value of both constant-rate and wrongly timed chronomodulated infusions. An automaton model for the cell cycle revealed the critical roles of variability in circadian entrainment and cell cycle phase durations in healthy tissues and tumours for the success of properly timed circadian delivery schedules. The models showed that additional therapeutic strategy further sets the constraints for the identification of the most effective chronomodulated schedules.

Altered Stra13 and Dec2 circadian gene expression in hypoxic cells

The circadian system regulates rhythmically most of the mammalian physiology in synchrony with the environmental light/dark cycle. Alteration of circadian clock gene expression has been associated with tumour progression but the molecular links between the two mechanisms remain poorly defined. Here we show that Stra13 and Dec2, two circadian transcriptional regulators which play a crucial role in cell proliferation and apoptosis are overexpressed and no longer rhythmic in serum shocked fibroblasts treated with CoCl(2,) a substitute of hypoxia. This effect is associated with a loss of circadian expression of the clock genes Rev-erbalpha and Bmal1, and the clock-controlled gene Dbp. Consistently, cotransfection assays demonstrate that STRA13 and DEC2 both antagonize CLOCK:BMAL1 dependent transactivation of the Rev-erbalpha and Dbp promoters. Using a transplantable osteosarcoma tumour model, we show that hypoxia is associated with altered circadian expression of Stra13, Dec2, Rev-erbalpha, Bmal1 and Dbp in vivo. These observations collectively support the notion that overexpression of Stra13 and Dec2 links hypoxia signalling to altered circadian clock gene expression.

Validation of Patient's Self-Reported Social Functioning As an Independent Prognostic Factor for Survival in Metastatic Colorectal Cancer Patients: Results of an International Study by the Chronotherapy Group of the European Organisation for Research and Treatment of Cancer

Purpose

A recent study identified a prognostic model for survival in metastatic colorectal cancer patients which included WBC count, alkaline phosphatase (AP), number of metastatic sites, and patients’ self-reported social functioning. The aim of this research is to validate this model on data from an independent sample.

Patients and Methods

This validation study is based on a prospective randomized controlled trial in patients with metastatic colorectal cancer conducted by the European Organisation for Research and Treatment of Cancer (EORTC) Chronotherapy Group. Overall, 564 patients in 10 countries were enrolled. For the purpose of this independent validation, patients with health-related quality of life (HRQOL) baseline data were analyzed. HRQOL was assessed using the EORTC Quality of Life Questionnaire C30 (QLQ-C30). The Cox proportional hazards regression model was used for both univariate and multivariate analyses of survival.

Results

The previous model with an additional adjustment, by stratification for sex, was replicated and its parameters were confirmed to independently predict survival: WBC count with an hazard ratio (HR) of 1.31 (95% CI, 1.021 to 1.698; P = .034); AP with an HR of 1.53 (95% CI, 1.188 to 1.979; P = .001); number of sites involved with an HR of 1.90 (95% CI, 1.531 to 2.364; P < .0001); and patients’ self-reported social functioning with an HR of 0.94 (95% CI, 0.905 to 0.976; P = .001). The latter translates into a 6% increase in the likelihood of an earlier death for every 10-point decrease in the social functioning scale of the EORTC QLQ-C30.

Conclusion

This study provides confirmatory evidence of the independent prognostic value of patients’ self-reported social functioning in patients with advanced colorectal cancer.

Complete Pathologic Response After Preoperative Chemotherapy for Colorectal Liver Metastases: Myth or Reality?

Purpose

Complete clinical response (CCR) of colorectal liver metastases (CLM) following chemotherapy is of limited predictive value for complete pathologic response (CPR) and cure of the disease. The objective of this study was to determine predictive factors of CPR as well as its impact on survival.

Patients and Methods

From January 1985 to July 2006, 767 consecutive patients with CLM underwent liver resection after systemic chemotherapy. Patients with CPR were compared with patients without CPR.

Results

Twenty-nine of 767 (4%) patients had CPR, and none of these 29 patients had CCR. Patients with CPR (mean age, 54 years) had a mean number of 3.3 metastases at diagnosis (mean size, 29.3 mm). Objective response and stable disease were observed in 79% and 21% of cases, respectively. Postoperative mortality rate was 0%. After a median follow-up of 52.2 months (range, 1.1 to 193.0 months), overall 5-year survival was 76% for patients with CPR compared with 45% for patients without CPR (P = .004). Independent predictive factors for CPR were: age ≤ 60 years, size of metastases ≤ 3 cm at diagnosis, carcinoembryonic antigen (CEA) level at diagnosis ≤ 30 ng/mL, and objective response following chemotherapy. The probability of CPR ranged from 0.2% when all factors were absent to 30.9% when all were present.

Conclusion

CPR was observed in 4% of patients with CLM treated with preoperative chemotherapy. However, CPR may occur in almost one-third of objective responders age ≤ 60 years with metastases ≤ 3 cm and low CEA values. CPR is associated with uncommon high survival rates.

Hepatic resection after rescue cetuximab treatment for colorectal liver metastases previously refractory to conventional systemic therapy

PURPOSE

In patients with unresectable colorectal liver metastases (CLM) resistant to first-line chemotherapy, the impact of cetuximab therapy on resectability is unknown. This study was performed to determine the post-cetuximab resectability rate and to examine postoperative outcomes for these heavily pretreated patients.

PATIENTS AND METHODS

From February 2004 to April 2006, we evaluated 151 patients with unresectable CLM resistant to initial chemotherapy and subsequently treated with systemic cetuximab. Resectability rates, patient outcomes, and tumoral and nontumoral liver pathology were assessed.

RESULTS

A total of 27 patients underwent surgery after a median of six cycles of cetuximab + irinotecan (20 of 27), oxaliplatin (four of 27), or both (one of 27). Eighteen patients (67%) had experienced treatment failure after at least two lines of chemotherapy before cetuximab. Twenty-five of the 27 patients who had surgery underwent hepatectomy: nine of 133 patients who were treated completely at our institution (resectability rate, 7%) and 16 of 18 patients who were referred from other institutions after systemic cetuximab therapy. Postoperative mortality was 3.7% (one of 27), with a complication rate of 50%. Histopathologic liver abnormalities were found in nine patients (36%), without specific lesions attributable to cetuximab. After median follow-up of 16 months, 23 of 25 patients who underwent resection (92%) were alive, and 10 patients (40%) were disease free. Median overall (OS) and progression-free survival (PFS) from initiation of cetuximab therapy were 20 and 13 months, respectively.

CONCLUSION

For CLM refractory to conventional chemotherapy, combination therapy with cetuximab increases resectability rates without increasing operative mortality or liver injury. The median OS and PFS of 20 and 13 months, respectively, suggest that this novel oncosurgical strategy benefits patients with previously refractory disease who respond subsequently to cetuximab.

Implications of circadian clocks for the rhythmic delivery of cancer therapeutics

The circadian timing system controls drug metabolism and cellular proliferation over the 24 h through molecular clocks in each cell, circadian physiology, and the suprachiasmatic nuclei--a hypothalamic pacemaker clock that coordinates circadian rhythms. As a result, both the toxicity and efficacy of over 30 anticancer agents vary by more than 50% as a function of dosing time in experimental models. The circadian timing system also down-regulates malignant growth in experimental models and possibly in cancer patients. Programmable-in-time infusion pumps and rhythmic physiology monitoring devices have made possible the application of chronotherapeutics to more than 2000 cancer patients without hospitalization. This strategy first revealed the antitumor efficacy of oxaliplatin against colorectal cancer. In this disease, international clinical trials have shown a five-fold improvement in patient tolerability and near doubling of antitumor activity through the chronomodulated, in comparison to constant-rate, delivery of oxaliplatin and 5-fluorouracil-leucovorin. Here, the relevance of the peak time, with reference to circadian rhythms, of the chemotherapeutic delivery of these cancer medications for achieving best tolerability was investigated in 114 patients with metastatic colorectal cancer and in 45 patients with non-small cell lung cancer. The incidence of severe adverse events varied up to five-fold as a function of the choice of when during the 24 h the peak dose of the medications was timed. The optimal chronomodulated schedules corresponded to peak delivery rates at 1 a.m. or 4 a.m. for 5-fluorouracil-leucovorin, at 1 p.m. or 4 p.m. for oxaliplatin, and at 4 p.m. for carboplatin. Sex of patient was an important determinant of drug schedule tolerability. This finding is consistent with recent results from a chronotherapy trial involving 554 patients with metastatic colorectal cancer, where sex also predicted survival outcome from chronotherapy, but not conventional drug delivery. Ongoing translational studies, mathematical modeling, and technology developments are further paving the way for tailoring cancer chronotherapeutics to the main rhythmic characteristics of the individual patient. Targeting therapeutic delivery to the dynamics of the cross-talk between the circadian clock, the cell division cycle, and pharmacology pathways represents a new challenge to concurrently improve the quality of life and survival of cancer patients through personalized cancer chronotherapeutics.

A cell cycle automaton model for probing circadian patterns of anticancer drug delivery

To optimize the temporal patterning of drug delivery used in cancer chronotherapy, we resort to an automaton model describing the transitions through the successive phases of the cell cycle. The model accounts for the progressive desynchronization of cells due to the variability of the durations of the cell cycle phases, and for the entrainment of the cell cycle by the circadian clock. Focusing on the cytotoxic effect of the anticancer drug 5-fluorouracil (5-FU), which kills cells in the S phase, we compare the effect of continuous infusion of 5-FU with various circadian patterns of 5-FU administration that peak either at 4 a.m., 10 a.m., 4 p.m., or 10 p.m. The model indicates that the cytotoxic effect of 5-FU is minimum for the circadian delivery peaking at 4 a.m., and maximum for the continuous infusion or the circadian pattern peaking at 4 p.m. These results fit well with experimental observations and illustrate how the modeling approach based on the cell cycle automaton may help to predict the cytotoxic effect of anticancer drugs affecting various phases of the cell cycle.

Time finding study of chronomodulated irinotecan (I), fluorouracil (F), leucovorin (L) and oxaliplatin (O) (chronoIFLO) against metastatic colorectal cancer: Results from randomized EORTC 05011 trial

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Background: We previously showed that a) irinotecan (I) could be combined with chronoFLO in MMC patients; b) least toxic times (LTT) for combined I and oxaliplatin respectively correspond to the middle of the rest-phase and the middle of acivity-phase in tumor-bearing mice; c) chrono I showed adequate activity in a randomized phase II trial; and d) MMC resistance can be partly overcome with chronoIFL. Methods: The objective was to identify the LTT for I characterized by a minimal dose reduction/delay among the first 3 courses (c). Assuming that the toxic effect of I had a 24-h periodicity patients were randomized in 6 groups with I peak delivery (180 mg/m2, 6-h sinusoidal infusion on day 1) at 1:00, 5:00, 9:00 am, 1:00, 5:00, or 9:00 pm. . All the groups received also chronoFLO on days 2–5, q 3 weeks (F 700 mg/m2/d & L 150 mg/m2/d; from 22:15 to 9:45 with peak delivery at 4:00 , O 20 mg/m2/d from 10:15 to 21:45, with peak delivery at 16:00). Based on a logistic regression model, a 15% reduction in toxic events in the first 3 c, 186 patients were considered necessary to estimate the LTT with a 95% CI (calculated by bootsrap) of less than 6 h. Results: 197 of 199 randomized MMC patients were considered for tolerability and safety with median age 61 years (30–81), sex (M 68% - F 32%) and PS (0/1/2 73/23/4%); therapy was 1st line in 77 patients and 2nd line in 23%. Thithy-one percent of severe protocol violations occurred, 16% of pump malfunctions (>10% dose delivery deviation). Median number of c was 6 (1–18). There were 3 toxic deaths. The observed LTT for I tolerability was 3:15 am (95 CI: 3:40–1:50 pm, NS). Grade 3–4 diarrhea ranged from 34 to 51.6% with LTT at 1:53 pm (4:29 -2:53 am, not significant, NS); neutropenia from 9 to 25% with LTT at 3:26 pm (10:50 - 4:55 am, NS). Age was a negative prognostic factor for diarrhea (p =0.01). Conclusion: This trial failed to show a statistically significant LTT for this combination in MCC patients. The safety profile of I combined with ChronoIFLO was acceptable, with diarrhea and neutropenia within previously reported range.

No significant financial relationships to disclose.

[Interactions between clock gene mutation, circadian phenotype and tumor growth in mice]

The relation between circadian physiology (rest-activity and body temperature) and the growth of a grafted tumor (Glasgow osteosarcoma-GOS) was investigated in the mice with mutation of clock gene (ClockDelta19(-)) or gene controlled by the clock (Vpac(-/-)). Circadian rhythms in temperature and activity were stable, with an approximately 24-h period in all the mice synchronized by the alternation of 12 h of light and 12 h of darkness (LD 12:12). Following exposure to constant darkness (DD), both rhythms persisted in ClockDelta19(-), yet with a lengthening of the period by 4.5 h compared to wild type. In DD, the amplitude increased by 45.9% for the temperature rhythm (p<0.001) and by 17.4% for the activity one (p=0.08) as compared to LD 12:12 in ClockDelta19(-). The improvement of circadian coordination and/or the lengthening of the circadian period observed in ClockDelta19(-) kept in DD was associated with a moderate slowing down of tumor growth. Although the exposure to DD ablated the activity and temperature rhythms in Vpac(-/-), no modification in tumor growth was observed as compared to wide type or Vpac(-/-) in LD 12:12. Major alternations of circadian physiology can result from interactions between photoperiodic environment and mutation of clock gene or gene controlled by the clock. In these conditions, we have shown that the alternation of the circadian phenotype does not seem to constitute an essential determinant of the growth of a grafted tumor.

[Dynamic circadian system patients under chimiotherapy]

Currently, the circadian timing system of cancer patients can be estimated with wrist actimetry, which provides numerical data on the continuous activity of patients. The method of processing of these data, which we implemented, aims at answering the following questions: is the circadian timing system stable before chemotherapy, is this system extensively modified by chemotherapy, are there structural modifications or a decrease in activity amplitude produced by chemotherapy and how does the circadian activity rhythm recover? Here, we determine a circadian model function using a wavelet transform prior to chemotherapy delivery. Then we measure the correlation between this model function and the evolution of the circadian rhythm of activity over the whole observation span during and after chemotherapy. The application of this method to the record of activity rhythms in cancer patients highlights the characteristics and the recovery pattern of chemotherapy-induced alterations of the circadian timing system.