Results from the UNITED study: a multicenter study validating the prognostic effect of the tumor-stroma ratio in colon cancer

BACKGROUND

The TNM (tumor-node-metastasis) Evaluation Committee of Union for International Cancer Control (UICC) and College of American Pathologists (CAP) recommended to prospectively validate the cost-effective and robust tumor-stroma ratio (TSR) as an independent prognostic parameter, since high intratumor stromal percentages have previously predicted poor patient-related outcomes.

PATIENTS AND METHODS

The 'Uniform Noting for International application of Tumor-stroma ratio as Easy Diagnostic tool' (UNITED) study enrolled patients in 27 participating centers in 12 countries worldwide. The TSR, categorized as stroma-high (>50%) or stroma-low (≤50%), was scored through standardized microscopic assessment by certified pathologists, and effect on disease-free survival (DFS) was evaluated with 3-year median follow-up. Secondary endpoints were benefit assessment of adjuvant chemotherapy (ACT) and overall survival (OS).

RESULTS

A total of 1537 patients were included, with 1388 eligible stage II/III patients curatively operated between 2015 and 2021. DFS was significantly shorter in stroma-high (n = 428) than in stroma-low patients (n = 960) (3-year rates 70% versus 83%; P < 0.001). In multivariate analysis, TSR remained an independent prognosticator for DFS (P < 0.001, hazard ratio 1.49, 95% confidence interval 1.17-1.90). As secondary outcome, DFS was also worse in stage II and III stroma-high patients despite adjuvant treatment (3-year rates stage II 73% versus 92% and stage III 66% versus 80%; P = 0.008 and P = 0.011, respectively). In stage II patients not receiving ACT (n = 322), the TSR outperformed the American Society of Clinical Oncology (ASCO) criteria in identifying patients at risk of events (event rate 21% versus 9%), with a higher discriminatory 3-year DFS rate (stroma-high 80% versus ASCO high risk 91%). A trend toward worse 5-year OS in stroma-high was noticeable (74% versus 83% stroma-low; P = 0.102).

CONCLUSION

The multicenter UNITED study unequivocally validates the TSR as an independent prognosticator, confirming worse outcomes in stroma-high patients. The TSR improved current selection criteria for patients at risk of events, and stroma-high patients potentially experienced chemotherapy resistance. TSR implementation in pathology diagnostics and international guidelines is highly recommended as aid in personalized treatment.

The value of post-operative chemotherapy after chemoradiotherapy in patients with high-risk locally advanced rectal cancer-results from the RAPIDO trial

BACKGROUND

Pre-operative chemoradiotherapy (CRT) rather than radiotherapy (RT) has resulted in fewer locoregional recurrences (LRRs), but no decrease in distant metastasis (DM) rate for patients with locally advanced rectal cancer (LARC). In many countries, patients receive post-operative chemotherapy (pCT) to improve oncological outcomes. We investigated the value of pCT after pre-operative CRT in the RAPIDO trial.

PATIENTS AND METHODS

Patients were randomised between experimental (short-course RT, chemotherapy and surgery) and standard-of-care treatment (CRT, surgery and pCT depending on hospital policy). In this substudy, we compared curatively resected patients from the standard-of-care group who received pCT (pCT+ group) with those who did not (pCT- group). Subsequently, patients from the pCT+ group who received at least 75% of the prescribed chemotherapy cycles (pCT ≥75% group) were compared with patients who did not receive pCT (pCT-/- group). By propensity score stratification (PSS), we adjusted for the following unbalanced confounders: age, clinical extramural vascular invasion, distance to the anal verge, ypT stage, ypN stage, residual tumour, serious adverse event (SAE) and/or readmission within 6 weeks after surgery and SAE related to pre-operative CRT. Cumulative probability of disease-free survival (DFS), DM, LRR and overall survival (OS) was analysed by Cox regression.

RESULTS

In total, 396/452 patients had a curative resection. The number of patients in the pCT+, pCT >75%, pCT- and pCT-/- groups was 184, 112, 154 and 149, respectively. The PSS-adjusted analyses for all endpoints demonstrated hazard ratios between approximately 0.7 and 0.8 (pCT+ versus pCT-), and 0.5 and 0.8 (pCT ≥75% versus pCT-/-). However, all 95% confidence intervals included 1.

CONCLUSIONS

These data suggest a benefit of pCT after pre-operative CRT for patients with high-risk LARC, with approximately 20%-25% improvement in DFS and OS and 20%-25% risk reductions in DM and LRR. Compliance with pCT additionally reduces or improves all endpoints by 10%-20%. However, differences are not statistically significant.

Adjuvant chemotherapy is superior to chemoradiation after D2 surgery for gastric cancer in the per-protocol analysis of the randomized CRITICS trial

BACKGROUND

The Intergroup 0116 and the MAGIC trials changed clinical practice for resectable gastric cancer in the Western world. In these trials, overall survival improved with post-operative chemoradiotherapy (CRT) and perioperative chemotherapy (CT). Intention-to-treat analysis in the CRITICS trial of post-operative CT or post-operative CRT did not show a survival difference. The current study reports on the per-protocol (PP) analysis of the CRITICS trial.

PATIENTS AND METHODS

The CRITICS trial was a randomized, controlled trial in which 788 patients with stage Ib-Iva resectable gastric or esophagogastric adenocarcinoma were included. Before start of preoperative CT, patients from the Netherlands, Sweden and Denmark were randomly assigned to receive post-operative CT or CRT. For the current analysis, only patients who started their allocated post-operative treatment were included. Since it is uncertain that the two treatment arms are balanced in such PP analysis, adjusted proportional hazards regression analysis and inverse probability weighted analysis were used to minimize the risk of selection bias and to estimate and compare overall and event-free survival.

RESULTS

Of the 788 patients, 478 started post-operative treatment according to protocol, 233 (59%) patients in the CT group and 245 (62%) patients in the CRT group. Patient and tumor characteristics between the groups before start of the post-operative treatment were not different. After a median follow-up of 6.7 years since the start of post-operative treatment, the 5-year overall survival was 57.9% (95% confidence interval: 51.4% to 64.3%) in the CT group versus 45.5% (95% confidence interval: 39.2% to 51.8%) in the CRT group (adjusted hazard ratio CRT versus CT: 1.62 (1.24-2.12), P = 0.0004). Inverse probability weighted analysis resulted in similar hazard ratios.

CONCLUSION

After adjustment for all known confounding factors, the PP analysis of patients who started the allocated post-operative treatment in the CRITICS trial showed that the CT group had a significantly better 5-year overall survival than the CRT group (NCT00407186).

Abstract P1-15-20: DIetary REstriction as an adjunct to neoadjuvant ChemoTherapy for HER2-negative breast cancer: Final results from the DIRECT trial (BOOG 2013-04)

Background:

Short term fasting (STF) protects from toxicity, while enhancing the efficacy of chemotherapy in cancer bearing mice and is a promising strategy to enhance the efficacy and tolerability of chemotherapy in humans. A specifically designed low calorie, low amino acid substitution diet (“Fasting Mimicking Diet”, FMD) has similar effects in vivo during chemotherapy as STF. The DIRECT trial evaluates the impact of FMD on toxicity and efficacy of neoadjuvant chemotherapy in women with HER2-negative early breast cancer.

Patients and methods:

Eligible patients had histologically confirmed, HER2-negative, stage II/III early breast cancer, adequate bone marrow, liver and renal function, BMI &gt; 19kg/m2 and absence of diabetes mellitus. Women receiving 8 neo-adjuvant AC-T courses (adriamycin/cyclophosphamide - docetaxel) or 6 FEC-T courses (5-fluorouracil, epirubicin and cyclophosphamide - docetaxel); day 1, q 3 weeks, were randomized to receive FMD or regular diet for 3 days prior to and at the day of chemotherapy and 3 days prior to surgery. The FMD group received no dexamethasone during the AC or FEC courses. The primary endpoint of the phase II part was feasibility and grade III/IV toxicity and of the phase III pathological complete response (pCR) rate. Additionally, in a side study increase in DNA damage in lymphocytes before and three hours after chemotherapy was compared between the 2 arms.

Results

From February 2014 to January 2018 131 patients from 11 participating Dutch centers were randomized, whereof 100 received AC-T and 31 received FEC-T. Sixty-six of the patients received FMD. Compliance to the diet was low as 32% fasted at least half of the cycles and 24% of patients fasted during all of cycles. The main reasons of non-compliance were food aversion induced by chemotherapy and the taste of the diet. Intention to treat grade III/IV toxicity was not significantly different between the standard arm (67,2%) and in the FMD arm (79,4%), although the majority of the toxicities in the FMD arm were assessed in patients that did not complete the FMD diet preceding the measurements. The total overall pCR rate was 12,8%, lower than assumed in the sample size calculation and would therefore need minimally a doubling in patient numbers to be able to reach the expected pCR difference between both arms. Due to the poor compliance, slow accrual rate and low overall pCR rate the DIRECT study terminated after completion of the phase II part. Subgroup analysis will be presented at SABCS. In a side study, DNA damage after chemotherapy was significantly less increased in lymphocytes in the FMD group as compared to the control group (p=0.043).

Conclusion

The effect of STF on toxicity and efficacy of chemotherapy was not established due to poor compliance, however STF by FMD reduced a transient increase in chemotherapy induced DNA damage. Close monitoring of patients by nutritionists with expertise in low calorie diets as well as diets with a more variable taste are probably needed to successfully examine the impact on adverse effects and tumor biology.

Citation Format: de Groot S, Lugtenberg RT, Welters MJ, Ehsan I, Vreeswijk MP, Smit VT, de Graaf H, Heijns JB, Portielje JE, van de Wouw AJ, Imholz AL, Kessels LW, Vrijaldenhoven S, Baars A, Meershoek-Klein Kranenbarg E, Duijm-de Carpentier M, van Leeuwen-Stok E, Putter H, Longo VD, van der Hoeven JJ, Nortier JW, Pijl H, Kroep JR. DIetary REstriction as an adjunct to neoadjuvant ChemoTherapy for HER2-negative breast cancer: Final results from the DIRECT trial (BOOG 2013-04) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-15-20.

Introduction of a colorectal cancer screening programme: results from a single-centre study

AIM

In 2014, a national colorectal cancer (CRC) screening programme was launched in the Netherlands. It is difficult to assess for the individual patients with CRC whether the oncological benefits of surgery will outweigh the morbidity of the procedure, especially in early lesions. This study compares patient and tumour characteristics between screen-detected and nonscreen-detected patients. Also, we present an overview of treatment options and clinical dilemmas when treating patients with early-stage colorectal disease.

METHOD

Between January 2014 and December 2016, all patients with nonmalignant polyps or CRC who were referred to the Department of Surgery of the Leiden University Medical Centre in the Netherlands were included. Baseline characteristics, type of treatment and short-term outcomes of patients with screen-detected and nonscreen-detected colorectal tumours were compared.

RESULTS

A total of 426 patients were included, of whom 240 (56.3%) were identified by screening. Nonscreen-detected patients more often had comorbidity (P = 0.03), the primary tumour was more often located in the rectum (P = 0.001) and there was a higher rate of metastatic disease (P < 0.001). Of 354 surgically treated patients, postoperative adverse events did not significantly differ between the two groups (P = 0.38). Of 46 patients with T1 CRC in the endoscopic resection specimen, 23 underwent surgical resection of whom only 30.4% had residual invasive disease at colectomy.

CONCLUSION

Despite differences in comorbidity, stage and surgical outcome of patients with screen-detected tumours compared to nonscreen-detected tumours were not significantly different. Considering its limited oncological benefits as well as the rate of adverse events, surgery for nonmalignant polyps and T1 CRC should be considered carefully.

Abstract P3-12-08: Evaluation of treatment compliance during extended endocrine therapy; secondary analysis of the IDEAL trial

In the first clinical trial reports about extended endocrine therapy in early breast cancer, treatment compliance appeared as a major concern. Earlier, it was shown in the IDEAL trial that approximately 35% of all patients stopped therapy before the allocated time. This additional study was conducted to evaluate the factors contributing to early treatment discontinuation.

Methods: In the IDEAL trial, a total of 1824 patients were randomized between either 2.5 or 5 years of extended letrozole, after 5 years of any adjuvant endocrine therapy. Only eligible patients who started therapy were included in the analysis. Adverse events were collected until 30 days after last treatment dose Reasons for ending therapy were collected prospectively at the time of treatment discontinuation.

Results: The majority of early treatment discontinuation was caused by adverse events (AEs) (n=372, 20.4% of all patients, 58% of all early treatment discontinuations). The most frequently reported AEs associated to treatment discontinuation were arthralgia (n=71, 9.9% of AEs associated treatment discontinuation), fatigue (n=48, 6.7%), depression (n=47, 6.5%), hot flashes (n=47, 6.5%) and alopecia (n=39, 5.4%). Of all AEs associated to early discontinuation, 86% was grade 1 or 2 (table 1). All grade 5 events were not associated to therapy.

Table 1 - Overview of adverse events most frequently associated to early treatment discontinuation Grade 1Grade 2Grade 3Grade 4Grade 5TotalArthralgia2236121071Fatigue192610148Depression202160047Hot flashes162092047Alopecia28731039Total (all AEs)30231680136720

Furthermore, the influence of previous type of adjuvant endocrine therapy was evaluated. Of all patients initiallytreated with 5 years of tamoxifen, 29% stopped due to an AE. In contrast, patients who were treated with aromatase inhibitors during the first 5 years, either with monotherapy or after 2-3 years of tamoxifen, stopped due to AEs in 22% and 18% respectively (Pearson Chi-square p-value 0.001). The average number of AEs per patient per previous treatment group was 2.27 for tamoxifen monotherapy, 2.03 for AI monotherapy and 1.73 in the sequential group. Corrected for the number of AEs in each group, patients pre-treated with 5 years of tamoxifen had a chance of treatment discontinuation of 12.7% per AE, compared to 10.8% and 10.4% for AI monotherapy and sequential therapy respectively. Additionally, of patients that completed regular adjuvant therapy between 1 and 2 years before randomization, 34% stopped due to adverse events. In contrast, of patients that completed therapy within 6 months before randomization stopped in 19% of all cases (Pearson Chi-square p-value &lt;0.001).

Conclusion: We have shown that adverse events are an important factor in early treatment discontinuation. Furthermore, the relation between adverse events and early discontinuation is influenced by the type of earlier therapy, with the highest rate of discontinuation for AI-naïve patients. This suggests that after 5 years of tamoxifen, patients are more inclined to stop therapy when encountering new AI-related adverse events compared to patients who were pre-treated with an AI.

Citation Format: Blok EJ, Kroep JR, Meershoek-Klein Kranenbarg E, Duijm-de Carpentier M, Nortier JWR, Rutgers EJTh, van de Velde CJH. Evaluation of treatment compliance during extended endocrine therapy; secondary analysis of the IDEAL trial [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-12-08.

Abstract S6-02: The efficacy and safety of the addition of ibandronate to adjuvant hormonal therapy in postmenopausal women with hormone-receptor positive early breast cancer. First results of the TEAM IIB trial (BOOG 2006-04)

Background:

Results of clinical trials concerning adjuvant bisphosphonates for the prevention of (bone) metastases in patients with early breast cancer are conflicting. A recent large meta-analysis, however, suggests that bisphosphonates reduce the incidence of (bone) metastases and improve skeletal-related events in early breast cancer patients. Subgroup analyses show that postmenopausal women seem to benefit the most. In this subgroup a modest overall survival benefit was observed with the addition of adjuvant bisphosphonates to standard adjuvant systemic therapy (EBCTCG, Lancet, 2015). TEAM IIB, a randomized phase III study (ISRCTN17633610), prospectively investigates the value of the addition of ibandronate to adjuvant hormonal therapy in postmenopausal women with hormone receptor-positive breast cancer.

Methods:

Postmenopausal women with stage I-III breast cancer and an indication for adjuvant hormonal treatment were randomized to receive at least 5 years of hormonal therapy (tamoxifen followed by at least 2-3 years exemestane, or in case of high risk at least 5 years of exemestane) with or without ibandronate 50mg orally, once daily for three years. Primary endpoint was disease-free survival (DFS). Secondary endpoints included time to and rate of bone metastases, other sites of recurrence, overall survival and safety. The study was amended because of slower than anticipated accrual and the sample size calculations were amended accordingly in June 2009. To detect a hazard ratio (HR) of 0.615 with a 2-sided alpha of 0.05 and a power of 0.8, 139 DFS-events were required in the intention-to-treat population.

Results: Between February 2007 and May 2014, 1116 patients were enrolled in 37 hospitals in the Netherlands of whom 40% had positive axillary lymph nodes and 56% of all patients received (neo)adjuvant chemotherapy (&gt;95% anthracyclines, 69% taxanes). Baseline characteristics were well balanced. At September 9, 2016, 143 DFS events had been reported. Median follow-up was 4.6 years and 80 patients were still on ibandronate treatment. Adherence to 3 years ibandronate was 67%, 21 patients randomized to receive ibandronate never started. 19 patients, of whom 9 in the control group were excluded because of major ineligibility.

In the ibandronate treated group 3-year DFS was 94.4% versus 90.8% in the control group (HR 0.84; 95% confidence interval [CI] 0.60-1.17). In total, 48 patients in the ibandronate versus 45 in the control group died, of whom 18 (37,5%) versus 28 (62,2%) of breast cancer. 3 years after randomization 1.6% of ibandronate treated patients developed bone metastases versus 4.6% in patients who were treated with adjuvant hormonal therapy only (HR 0.76; [CI] 0.43-1.32). 14 (29,2%) versus 9 (20%) of patients died because of secondary malignancies respectively.

There was no significant difference in creatinine clearance during the first three years after randomization. 36 Serious adverse events (SAEs) were reported in the ibandronate group versus 51 in the control group. Of patients randomized to ibandronate 4 developed osteonecrosis, but without residual complaints.

Conclusion: So far, at a median follow-up of 4.6 years there is no statistically significant benefit from adding ibandronate to adjuvant hormonal treatment in postmenopausal women with hormone-receptor positive early breast cancer. However, since hazard rates are in favor of ibandronate longer follow-up is warranted before final conclusions can be drawn.

Citation Format: Vliek SB, Meershoek-Klein Kranenbarg E, van Rossum AGJ, Tanis BC, Putter H, van der Velden AWG, Hendriks MP, van Bochove A, van Riet Y, van Leeuwen-Stok AE, Tjan-Heijnen VCG, Kroep JR, Nortier JWR, van de Velde CJH, Linn SC. The efficacy and safety of the addition of ibandronate to adjuvant hormonal therapy in postmenopausal women with hormone-receptor positive early breast cancer. First results of the TEAM IIB trial (BOOG 2006-04) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S6-02.

Specific adverse events are associated with response to exemestane therapy in postmenopausal breast cancer patients: Results from the TEAMIIA study (BOOG2006-04)

PURPOSE

In the adjuvant setting, specific adverse events (AEs) such as vasomotor symptoms (VMS) and musculoskeletal AEs are associated with relapse-free survival in aromatase inhibitor (AI)-treated patients. In the neoadjuvant setting, specific AEs may be associated with tumor response to AIs as well.

METHODS

Between 2007 and 2012, 107 patients participated in the prospective TEAMIIA trial, a prospective, phase II trial investigating 6 months of neoadjuvant exemestane in patients with strongly ER-positive breast cancer. Radiological response (≥30% decrease in tumor size) was studied in relation to VMSs and MSAEs. Pearson's Chi-Square tests and multivariate logistic regression analyses were used to evaluate of statistical significance (p < 0.05).

RESULTS

Out of 102 patients 26 patients (25.4%) experienced at least one episode of VMS and 27 patients (26.4%) experienced MSAE. Out of 240 reported adverse events, 71 were specific AEs (40 MSAEs, 31 VMSs). Radiological response was greater in patients who reported VMSs compared to patients who did not (70.8% vs. 49.3%, multivariate OR 2.91, 95% C.I. 1.03-8.26, P = 0.045). No significant advantage towards better response was observed in patients who experienced MSAEs (60.0% vs. 53.3%, univariate OR 1.33, 95% C.I. 0.53-3.38, P = 0.545).

CONCLUSION

VMSs are associated with tumor response to neoadjuvant exemestane and may be useful for predicting treatment outcomes of AI treatment at an early stage in patients treated with neoadjuvant AIs.

Vitamin D (25-0H D3) status and pathological response to neoadjuvant chemotherapy in stage II/III breast cancer: Data from the NEOZOTAC trial (BOOG 10-01)

BACKGROUND

Serum levels of 25-OH vitamin D3 (vitamin D) have been shown to be prognostic for disease-free survival in patients with breast cancer. We investigated the predictive value of these levels for pathological response after neoadjuvant chemotherapy in patients with breast cancer taking part in the NEOZOTAC phase-III trial. Additionally, the effect of chemotherapy on vitamin D levels was studied.

MATERIALS AND METHODS

Serum vitamin D was measured at baseline and before the last cycle of chemotherapy. The relationship between these measurements and clinical outcome, as defined by pathological complete response in breast and lymph nodes (pCR) was examined.

RESULTS

Baseline and end of treatment vitamin D data were available in 169 and 91 patients, respectively. Median baseline vitamin D values were 58.0 nmol/L. In patients treated with chemotherapy only, serum vitamin D levels decreased during neoadjuvant chemotherapy (median decrease of 16 nmol/L, P = 0.003). The prevalence of vitamin D levels < 50 nmol/L increased from 38.3% at baseline to 55.9% after chemotherapy. In the total population, baseline and end of therapy vitamin D levels were not related to pathological response. No associations were found between pCR and vitamin D level changes.

CONCLUSION

The significant decrease in vitamin D post-neoadjuvant chemotherapy suggests that vitamin D levels should be monitored and in case of decrease of vitamin D levels, correction may be beneficial for skeletal health and possibly breast cancer outcome.

Dynamic prediction in breast cancer: proving feasibility in clinical practice using the TEAM trial

BACKGROUND

Predictive models are an integral part of current clinical practice and help determine optimal treatment strategies for individual patients. A drawback is that covariates are assumed to have constant effects on overall survival (OS), when in fact, these effects may change during follow-up (FU). Furthermore, breast cancer (BC) patients may experience events that alter their prognosis from that time onwards. We investigated the 'dynamic' effects of different covariates on OS and developed a nomogram to calculate 5-year dynamic OS (DOS) probability at different prediction timepoints (tP) during FU.

METHODS

Dutch and Belgian postmenopausal, endocrine-sensitive, early BC patients enrolled in the TEAM trial were included. We assessed time-varying effects of specific covariates and obtained 5-year DOS predictions using a proportional baselines landmark supermodel. Covariates included age, histological grade, hormone receptor and HER2 status, T- and N-stage, locoregional recurrence (LRR), distant recurrence, and treatment compliance. A nomogram was designed to calculate 5-year DOS based on individual characteristics.

RESULTS

A total of 2602 patients were included (mean FU 6.2 years). N-stage, LRR, and HER2 status demonstrated time-varying effects on 5-year DOS. Hazard ratio (HR) functions for LRR, high-risk N-stage (N2/3), and HER2 positivity were HR = (8.427 × 0.583[Formula: see text], HR = (3.621 × 0.816[Formula: see text], and HR = (1.235 × 0.851[Formula: see text], respectively. Treatment discontinuation was associated with a higher mortality risk, but without a time-varying effect [HR 1.263 (0.867-1.841)]. All other covariates were time-constant.

DISCUSSION

The current nomogram accounts for elapsed time since starting adjuvant endocrine treatment and optimizes prediction of individual 5-year DOS during FU for postmenopausal, endocrine-sensitive BC patients. The nomogram can facilitate in determining whether further therapy will benefit an individual patient, although validation in an independent dataset is still needed.

Abstract P3-06-50: Thyroid function is associated with the response to neoadjuvant chemotherapy in breast cancer patients: Results from the NEOZOTAC trial on behalf of the Dutch Breast Cancer Research Group (BOOG 2010-01)

Background: Thyroid hormones, regulators of metabolism and development in healthy tissue, stimulate tumor growth in vitro and are associated with breast cancer risk. We investigated the effect of chemotherapy on thyroid function and the extent to which it can predict the pathological response in patients with HER2 negative stage II/III breast cancer taking part in the NEOZOTAC phase III trial, randomizing between 6 cycles of neoadjuvant TAC chemotherapy with or without additional zoledronic acid. Moreover, we examined the impact of thyroid function on chemotherapy toxicity.

Methods: Serum samples of 38 of the 105 patients who participated in the side study of the NEOZOTAC trial were available for analyses. Serum free thyroxin (fT4) and thyroid stimulating hormone (TSH) levels were measured at baseline and compared with fT4 and TSH levels before the 2nd and 6th chemotherapy cycle. FT4 and TSH levels were also compared between subjects with and without pathological complete response (pCR). The relation between toxicity, per side effect of any CTC grade, and the variation in fT4 and TSH levels during chemotherapy was tested.

Results: Serum samples at baseline, before the 2nd chemotherapy cycle and at end of treatment were available for 31, 30 and 21 patients, respectively. In the total population, the mean baseline fT4 level was 16,0pmol/L and the mean TSH level 1,11mU/L. There were no differences between subjects solely treated with TAC chemotherapy and subjects treated with zoledronic acid as an adjunct to TAC with respect to the mean fT4 and TSH at each time point. Baseline TSH levels tended to be higher in patients who achieved pCR (p=0.035 univariate analysis and p=0.074 multivariate analysis) (Table 1). During 6 cycles of chemotherapy, fT4 levels decreased (p&lt;0.000) and TSH levels increased significantly (p=0.019). Interestingly, the decrease of fT4 was significantly greater in patients without nausea, vomiting or sensory neuropathy, than in patients with those side effects (p=0.037, p=0.043 and p=0.050 respectively).

CharacteristicUnivariate analysisMultivariate analysis OR95%CIP valueOR95%CIP valueN stage: N0 vs. N+0.330.03-3.640.368T stage: &lt;5cm vs. &gt;5cm0.330.03-3.630.333ER receptor: Pos vs. Neg2.560.20-33.10.473fT40.780.43-1.420.4170.660.33-1.290.581TSH3.241.09-9.700.03517.30.76-3910.074Table 1. Univariate and multivariate logistic regression models of baseline characteristics and TSH and fT4 predictive of pCR.

Conclusion: TSH levels at baseline were higher in breast cancer patients with pCR. Chemotherapy blunts thyroid function, and a large decline of fT4 was associated with less side effects. These data suggest that thyroid hormones may interact with chemotherapy to modulate treatment (side-) effects in patients with breast cancer.

Citation Format: S de Groot, A Charehbili, L GM Janssen, E M Dijkgraaf, V THBM Smit, L W Kessels, A van Bochove, H WM van Laarhoven, E Meershoek-Klein Kranenbarg, A E van Leeuwen-Stok, G J Liefers, C JH van de Velde, J WR Nortier, J JM van der Hoeven, H Pijl, J R Kroep. Thyroid function is associated with the response to neoadjuvant chemotherapy in breast cancer patients: Results from the NEOZOTAC trial on behalf of the Dutch Breast Cancer Research Group (BOOG 2010-01) [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-06-50.

Long term effects of extended adjuvant endocrine therapy on quality of life in breast cancer patients

OBJECTIVES

The standard treatment for hormone-receptor positive, postmenopausal early breast cancer patients is 5 years of adjuvant endocrine therapy. Previous studies demonstrate that prolonging adjuvant endocrine therapy may improve disease-free survival. However, endocrine therapy is known for its adverse events, which may negatively affect Quality of Life (QoL). The aim of this study is to assess the impact of extended adjuvant endocrine therapy on long-term QoL outcomes.

METHODS

471 patients selected from the IDEAL trial were invited to complete a questionnaire 1-1.5 years after starting with extended therapy. The questionnaire consisted of the EORTC QLQ-C30 and QLQ-BR23 questionnaires. Mean QoL outcomes were compared with EORTC reference values for stage I and II breast cancer patients and the general population. Furthermore, QoL outcomes were compared between different treatment regimens. A difference of eight points was considered clinically relevant.

RESULTS

IDEAL patients receiving extended adjuvant endocrine therapy have significantly and clinically relevant better global QoL compared with reference values for stage I and II breast cancer patients (79.6 versus 64.6; p < 0.01) and the general population (79.6 versus 71.2; p < 0.01). Similar results were found for emotional function, pain, appetite loss, diarrhea and financial problems. Between treatment regimens prior to extended adjuvant endocrine therapy, differences were only found on specific QoL domains (e.g. arm symptoms).

CONCLUSION

Breast cancer patients on extended adjuvant endocrine therapy have significantly and clinically relevant better global QoL compared with other stage I-II breast cancer patients and the general population, 6-8.5 years after diagnosis.

Disorganised stroma determined on pre-treatment breast cancer biopsies is associated with poor response to neoadjuvant chemotherapy: Results from the NEOZOTAC trial

INTRODUCTION

The tumor-associated stroma is of importance for tumor progression and is generally accepted to have a significant influence on patient prognosis. However, little is known regarding specific features of tumor-associated stromal tissues and response to (neoadjuvant) chemotherapy. This study investigated the predictive value of extracellular matrix organization on response to chemotherapy in patients treated in the NEOZOTAC trial.

METHODS

Stromal organisation was analyzed via a simple method using image analysis software on hematoxylin and eosin (H&E)-stained slides from primary tumor biopsies collected as part of the NEOZOTAC trial. Heidenhain's AZAN trichrome-stained slides were also analyzed for comparison of collagen evaluation. Sections were stained for phospho-Smad2 (pS2) in order to determine the relationship of TGF-β signaling with stromal organization.

RESULTS

A statistically significant relationship was observed between stroma consisting of organised collagen and pathological response to neoadjuvant chemotherapy (Odds Ratio 0.276, 95%CI 0.124-0.614, P = 0.002). This parameter was also related to ER-status (P = 0.003), clinical tumor -status (P = 0.041), nodal status (P = 0.029) and pS2 status (P = 0.025). Correlation between stromal organisation determined on H&E-stained and AZAN-stained tissue sections was high (Pearson's correlation coefficient = 0.806).

CONCLUSION

Intratumoral stromal organisation determined using pre-treatment breast cancer biopsies was related to pathological response to chemotherapy. This parameter might play a role in the management of breast cancer for identifying those patients that are likely to benefit from neoadjuvant chemotherapy.

Adjuvant chemotherapy for rectal cancer patients treated with preoperative (chemo)radiotherapy and total mesorectal excision: a Dutch Colorectal Cancer Group (DCCG) randomized phase III trial

BACKGROUND

The discussion on the role of adjuvant chemotherapy for rectal cancer patients treated according to current guidelines is still ongoing. A multicentre, randomized phase III trial, PROCTOR-SCRIPT, was conducted to compare adjuvant chemotherapy with observation for rectal cancer patients treated with preoperative (chemo)radiotherapy and total mesorectal excision (TME).

PATIENTS AND METHODS

The PROCTOR-SCRIPT trial recruited patients from 52 hospitals. Patients with histologically proven stage II or III rectal adenocarcinoma were randomly assigned (1:1) to observation or adjuvant chemotherapy after preoperative (chemo)radiotherapy and TME. Radiotherapy consisted of 5 × 5 Gy. Chemoradiotherapy consisted of 25 × 1.8-2 Gy combined with 5-FU-based chemotherapy. Adjuvant chemotherapy consisted of 5-FU/LV (PROCTOR) or eight courses capecitabine (SCRIPT). Randomization was based on permuted blocks of six, stratified according to centre, residual tumour, time between last irradiation and surgery, and preoperative treatment. The primary end point was overall survival.

RESULTS

Of 470 enrolled patients, 437 were eligible. The trial closed prematurely because of slow patient accrual. Patients were randomly assigned to observation (n = 221) or adjuvant chemotherapy (n = 216). After a median follow-up of 5.0 years, 5-year overall survival was 79.2% in the observation group and 80.4% in the chemotherapy group [hazard ratio (HR) 0.93, 95% confidence interval (CI) 0.62-1.39; P = 0.73]. The HR for disease-free survival was 0.80 (95% CI 0.60-1.07; P = 0.13). Five-year cumulative incidence for locoregional recurrences was 7.8% in both groups. Five-year cumulative incidence for distant recurrences was 38.5% and 34.7%, respectively (P = 0.39).

CONCLUSION

The PROCTOR-SCRIPT trial could not demonstrate a significant benefit of adjuvant chemotherapy with fluoropyrimidine monotherapy after preoperative (chemo)radiotherapy and TME on overall survival, disease-free survival, and recurrence rate. However, this trial did not complete planned accrual.

REGISTRATION NUMBER

Dutch Colorectal Cancer group, CKTO 2003-16, ISRCTN36266738.

Addition of zoledronic acid to neoadjuvant chemotherapy does not enhance tumor response in patients with HER2-negative stage II/III breast cancer: the NEOZOTAC trial (BOOG 2010-01)

BACKGROUND

The role of zoledronic acid (ZA) when added to the neoadjuvant treatment of breast cancer (BC) in enhancing the clinical and pathological response of tumors is unclear. The effect of ZA on the antitumor effect of neoadjuvant chemotherapy has not prospectively been studied before.

PATIENTS AND METHODS

NEOZOTAC is a national, multicenter, randomized study comparing the efficacy of TAC (docetaxel, adriamycin and cyclophosphamide i.v.) followed by granulocyte colony-stimulating factor on day 2 with or without ZA 4 mg i.v. q 3 weeks inpatients withstage II/III, HER2-negative BC. We present data on the pathological complete response (pCR in breast and axilla), on clinical response using MRI, and toxicity. Post hoc subgroup analyses were undertaken to address the predictive value of menopausal status.

RESULTS

Addition of ZA to chemotherapy did not improve pCR rates (13.2% for TAC+ZA versus 13.3% for TAC). Postmenopausal women (N = 96) had a numerical benefit from ZA treatment (pCR 14.0% for TAC+ZA versus 8.7% for TAC, P = 0.42). Clinical objective response did not differ between treatment arms (72.9% versus 73.7%). There was no difference in grade III/IV toxicity between treatment arms.

CONCLUSIONS

Addition of ZA to neoadjuvant chemotherapy did not improve pathological or clinical response to chemotherapy. Further investigations are warranted in postmenopausal women with BC, since this subgroup might benefit from ZA treatment.

Abstract P1-08-19: Changes in circulating vitamin D levels as a predictor for pathological response to neoadjuvant chemotherapy (NAC) in breast cancer (BC): A Dutch breast cancer trialists group (BOOG) side-study

Background:

Vitamin D (vit D) status is suggested to be of prognostic value for treatment outcome in women with breast cancer. However, there are no data of the predictive value of vit D status and changes of vit D levels for response to neoadjuvant chemotherapy (NAC).

Methods:

A subset of patients (pts) from the NEOZOTAC trial in whom vit D data were available was evaluated. NEOZOTAC is a randomized phase III study comparing the efficacy of NCT with or without zoledronic acid (ZA) in pts with stage II/III, measurable, HER2-negative BC. Vit D deficiency and severe deficiency were defined as vit D levels of ≤ 50 and ≤25 nmol/L, respectively. Baseline vit D levels were available for correlation to pathological response of 165 pts (83 ZA-arm), while 67 pts (35 ZA arm) could be evaluated for changes in vit D levels between baseline and cycle 6. Pts who were allocated to the ZA arm should by protocol receive daily supplements of calcium/vit D 500/400 IU. Pathological response was assessed using the Miller and Payne scoring system; pathological complete response (pCR) was defined as absence of tumor cells in the tumor bed and good response was defined as ≥90% decrease of tumor cellularity.

Results:

Vit D was measured in 168 pts and was done in 75% of pre/perimenopausal pts and 51.3% of postmenopausal pts. There was no significant relation between baseline vit D deficiency (&lt; 50 nmol/L) and pCR (pCR 25.8% for deficient pts vs. 14.1% for non-deficient pts, P = 0.06). Pts with severe vit D deficiency (&lt;25 nmol/L) tended to respond less (pCR 10.5 vs 19.9%, p = 0.53). At the end of chemotherapy, good pathological responders seemed to have a slight increase in vit D levels compared to non-responders who rather showed a decrease (mean 1.11 vs. -9.71, P = 0.08). After multivariate analysis correcting for menopausal status and treatment arm, this result was significant (P = 0.03, 95% C.I. 1.004-1.055). When pts in the ZA arm were analyzed separately, again, good response was rather associated with an increase than a decrease (mean = 9.8 vs. -1.6, P = 0.12). From 17 out of 35 ZA treated pts who were vit D deficient at baseline, only 5 (29.4%) reached levels &gt;50 nmol/L at the end of treatment.

Conclusions:

Baseline vit D status was not predictive for pCR. However, increase in vit D levels during therapy tended to be associated with better pathological response. Therefore, achieving higher vit D levels can be important. Daily suppletion with calcium/ vitamin D 500/400 might be inadequate for achieving sufficient levels after NAC.

Contact information:

Dr. J.R. Kroep, M.D., Ph.D., Department of Medical Oncology, email:j.r.kroep@lumc.nl or A. Charehbili, BSc. Department of Surgery and Medical Oncology, email: a.charehbili@lumc.nl or LUMC datacenter, Department of Surgery, phone +31(0)71-5263500, fax +31(0)71-5266744, email: datacenter@lumc.nl, Leiden University Medical Center (LUMC), Leiden, The Netherlands.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-08-19.

Abstract P1-06-04: The predictive value of tumor-stroma ratio for radiological and pathological response to neoadjuvant chemotherapy in breast cancer (BC): A Dutch breast cancer trialists’ group (BOOG) side-study

Background

Intra-tumoral stroma interacts with tumor cells and has a profound effect on tumor behavior. The tumor-stroma ratio (TSR) is of prognostic value in BC and other types of solid tumors. However, the predictive value of this parameter for achieving pathological complete response (pCR) after neoadjuvant chemotherapy is unknown.

Methods

We evaluated the relation between TSR and neoadjuvant treatment response in a retrospective cohort of 69 patients (pts) treated with various regimens of neoadjuvant chemotherapy at our institution who were diagnosed with BC between 1991 and 2007 and of whom radiological response was recorded. The percentage of intra-tumoral stroma was visually estimated on diagnostic sections from primary tumor tissue by two observers. The cut-off point between stroma-rich and stroma-poor tumors was set to 50% (as determined in previous investigations). These results were validated in a cohort from the NEOZOTAC trial: a national, multicenter, randomized study comparing the efficacy of TAC (docetaxel, adriamycin and cyclophosphamide i.v. day 1) chemotherapy with or without zoledronic acid 4 mg i.v., q 3 weeks, 6 times in 250 pts with stage II/III, measurable, HER2-negative BC. Radiological response (complete or partial) was evaluated following RECIST 1.1 criteria. pCR was centrally revised and defined as absence of residual tumor cells in the original tumor bed.

Results

In the retrospective cohort (n = 69) 62.3% of the specimens were classified as stroma-rich. In univariate analysis TSR was significantly associated with radiological response (76.0% stroma-poor vs. 48.8% stroma-rich, P = 0.03). This finding persisted after multivariate analysis for T-status, N-status and ER-status (Odds Ratio [OR] 0.17, 95% C.I.: 0.04-0.78). In the validation set, in which 47.9% of the specimens were stroma-rich (211 cases evaluated), TSR did not predict for radiological response (79.5% stroma-poor vs. 79.2%, P = 0.96). However, when validation data were split on basis of ER-status, TSR was a significant and independent predictor for radiological response in ER-negative pts. (89.5% vs. 50%, P = 0.048, 95% C.I.: 0.01 - 0.98). In the validation set, TSR predicted for pCR with greater pCR rates in stroma-poor tumors (P = 0.03, 22.7% vs 10.3%). Final response results of the pilot and the enlarged sample size of all 250 pts of the validation set will be presented.

Conclusions

TSR might be a marker for radiological and pathological response to neoadjuvant chemotherapy, especially for the ER- tumor subgroup. Considering the simplicity and low cost of TSR assessment, it should be further evaluated and will be prospectively studied in the next neoadjuvant chemotherapy trial of the BOOG.

Contact information:

Dr. J.R. Kroep, M.D., Ph.D., Department of Medical Oncology, email:j.r.kroep@lumc.nl or T.J.A. Dekker, MSc. Department of Surgery and Medical Oncology, email: t.j.a.dekker@lumc.nl or LUMC datacenter, Department of Surgery, phone +31(0)71-5263500, fax +31(0)71-5266744, email: datacenter@lumc.nl, Leiden University Medical Center (LUMC), Leiden, The Netherlands.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-06-04.

Relationship between specific adverse events and efficacy of exemestane therapy in early postmenopausal breast cancer patients

BACKGROUND

Many adverse events (AEs) associated with aromatase inhibitors (AIs) involve symptoms related to the depletion of circulating estrogens, and may be related to efficacy. We assessed the relationship between specific AEs [hot flashes (HF) and musculoskeletal AEs (MSAE)] and survival outcomes in Dutch and Belgian patients treated with exemestane (EXE) in the Tamoxifen Exemestane Adjuvant Multinational (TEAM) trial. Additionally, the relationship between hormone receptor expression and AEs was assessed.

METHODS

Efficacy end points were relapse-free survival (RFS), overall survival (OS) and breast cancer-specific mortality (BCSM), starting at 6 months after starting EXE treatment. AEs reported in the first 6 months of treatment were included. Specific AEs comprised HF and/or MSAE. Landmark analyses and Cox proportional hazards models assessed survival differences up to 5 years.

RESULTS

A total of 1485 EXE patients were included. Patients with HF had a better RFS than patients without HF [multivariate hazard ratio (HR) 0.393, 95% confidence interval (CI) 0.19-0.813; P = 0.012]. The occurrence of MSAE versus no MSAE did not relate to better RFS (multivariate HR 0.677, 95% CI 0.392-1.169; P = 0.162). Trends were maintained for OS and BCSM. Quantitative hormone receptor expression was not associated with specific AEs.

CONCLUSIONS

Some AEs associated with estrogen depletion are related to better outcomes and may be valuable biomarkers in AI treatment.

Transanal endoscopic microsurgery versus total mesorectal excision of T1 rectal adenocarcinomas with curative intention

PURPOSE

After total mesorectal excision (TME) for rectal cancer, pathology is standardized with margin status as a predictor for recurrence. This has yet to be implemented after transanal endoscopic microsurgery (TEM) and was investigated prospectively for T1 rectal adenocarcinomas.

PATIENTS AND METHODS

Eighty patients after TEM were compared to 75 patients after TME. The study protocol included standardized pathology. TEM patients were eligible when excision margins were negative.

RESULTS

TEM was safer than TME as reflected by operating time, blood loss, hospital stay, morbidity, re-operation rate and stoma formation (all P<0.001). Mortality after TEM was 0% and after TME 4%. At 5 years after TEM and TME, both overall survival (TEM 75% versus TME 77%, P=0.9) and cancer-specific survival (TEM 90% versus TME 87%, P=0.5) were comparable. Local recurrence rate after TEM was 24% and after TME 0% (HR 79.266, 95% CI, 1.208 to 5202, P<0.0001).

CONCLUSION

For T1 rectal adenocarcinomas TEM is much saver than TME and survival is comparable. After TEM local recurrence rate is substantial, despite negative excision margins.

Improved survival after resectable non-cardia gastric cancer in The Netherlands: the importance of surgical training and quality control

BACKGROUND

In The Netherlands, standardised limited D1 and extended D2 lymph node dissections in the treatment of resectable gastric cancer were introduced nationwide within the framework of the Dutch D1-D2 Gastric Cancer Trial between 1989 and 1993. In a population-based study, we evaluated whether the survival of patients with resectable gastric cancer improved over time on a regional level.

METHODS

We compared 5-year overall and relative survival of patients with curatively resected non-cardia gastric cancer in the regional cancer registry of the Comprehensive Cancer Centre West in The Netherlands before the Dutch D1-D2 trial (1986 to mid 1989; n = 273), during the trial period (mid 1989 to mid 1993; n = 255), and after the trial (mid 1993 to 1999; n = 219), adjusting for prognostic variables.

RESULTS

Unadjusted survival was highest in the post-trial period: 5-year overall and relative survival were 42% and 52%, respectively, compared to 34% and 41% in the pre-trial period, and 39% and 46% in the trial period (p = 0.31 and p = 0.06, respectively). After adjustment for age, gender, tumour site, pT-stage, nodal status and hospital volume, the effect of period on survival was more apparent (p = 0.009). Compared to the pre-trial period, the hazard ratio was 0.83 (95% confidence interval, 0.68-1.02) for the trial period, and 0.72 (0.58-0.89) after the trial. Less than 1% of the patients received adjuvant therapy.

CONCLUSION

Survival of patients with curatively resected non-cardia gastric cancer has improved. Standardisation and surgical training in D1 and D2 lymph node dissection are the most likely explanation for this improvement.

Risk factors for sexual dysfunction after rectal cancer treatment

This study aimed to identify risk factors for long-term sexual dysfunction (SD) after rectal cancer treatment. Patients with resectable rectal cancer were randomised to total mesorectal excision with or without preoperative radiotherapy (PRT). Preoperatively and at 3, 6, 12, 18 and 24 months postoperatively, SD scores were filled out in questionnaires. Possible risk factors for postoperative deterioration of sexual functioning, including patients' demographics, tumour-specific factors and treatment-related variables, were investigated with univariate and multivariable regression analyses. Increase in general SD, erectile dysfunction and ejaculatory problems were reported by 76.4, 79.8 and 72.2 percent of the male patients, respectively. Risk factors were nerve damage, blood loss, anastomotic leakage, PRT and the presence of a stoma. In female patients, increase in general SD, dyspareunia and vaginal dryness were reported by 61.5, 59.1 and 56.6 percent, respectively. This was associated with PRT and the presence of a stoma. SD occurs frequently after rectal cancer treatment and is caused by surgical (nerve) damage with an additional effect of PRT. Patients should be informed preoperatively, and education of surgeons in neuroanatomy may provide the key to the improvement of functional outcome.