The value of magnetic resonance imaging in esophageal carcinoma: Tool or toy?

Currently, the use of magnetic resonance imaging (MRI) in patients with esophageal carcinoma is limited. However, the quality of MRI for esophageal carcinoma continues to improve and the importance of MRI in patients with esophageal carcinoma has been gradually recognized. Compared with endoscopic ultrasound and computed tomography applied in T and N staging, MRI has now achieved excellent results after the imaging technique has been optimized. We review the literature on MRI and discuss the future of MRI in esophageal carcinoma. While the role of MRI in staging, tumor volume target delineation and evaluation for preoperative chemoradiotherapy, prognosis and recurrence is still evolving. The application of MRI in esophageal carcinoma has a bright future and potential to improve precision of T and N staging as well as treatment delivery.     

Lobular breast cancer: how useful is breast magnetic resonance imaging?

RATIONALE AND OBJECTIVES: To review magnetic resonance imaging (MRI) findings in lobular breast carcinoma, the in situ or infiltrating subtype, with special attention to the dynamic curves with the aim to evaluate possible differences with ductal carcinoma. METHODS: In 2 years, 27 patients with lobular and one with tubular carcinoma underwent MRI at the Istituto Nazionale Tumori of Milan. RESULTS: All lobular carcinomas demonstrated early or late enhancement (100% sensitivity), without significant differences in morphology compared with ductal carcinoma, but frequently with a different shape of the dynamic curves. CONCLUSIONS: Due to its infiltrative growth associated to only limited connective tissue reaction, lobular carcinoma often encounters difficulties in mammographic diagnosis. In contrast, MRI can be very helpful in evaluating the true extension of the disease, especially when breast conservation is considered. Due to a more consistent fibrotic stroma, these lesions sometimes show a delayed enhancement, which suggests that more than one set of subtracted images should be evaluated during MRI analysis.     

Overview of preoperative radiochemotherapy in breast cancer: past or future?

Radiochemotherapy is a standard approach in human solid tumours, with localised stage and radical treatment intention. In the early-intermediate stages of breast cancer model, neoadjuvant radiochemotherapy is an alternative to induction chemotherapy alone and might further impact the surgical technical treatment characteristics (a downsizing effect). In the era of targeted therapy and personalised treatment for breast cancer patients with initial localised disease, radiochemotherapy needs to be explored as a component of optimised local treatment to potentially improve relevant local results, such as breast conservation, breast cosmesis and individualised breast cancer radiochemotherapy response prediction. An overview of available literature data regarding neoadjuvant treatment including radiotherapy component is analysed and discussed.     

Is preoperative ultrasound of the axilla necessary in screen-detected breast cancer?

BackgroundAxillary ultrasound (US) with fine needle aspiration biopsy (FNAB) of suspicious lymph nodes helps identify patients with axillary metastases preoperatively avoiding a 2-step axillary procedure. However, it does not accurately differentiate between low and high axillary tumour burden. Our aim was to determine the rationale of preoperative axillary US in screen-detected breast cancer.MethodsWe retrospectively analysed patients, aged between 50 and 69 years, which had an invasive breast cancer diagnosed in the Slovenian National Breast Cancer Screening program between January 2012 and June 2017. Proportion of patients that proceeded directly to ALND and the proportion of patients with unnecessary ALND as a result of positive US-FNAB were calculated.ResultsAltogether 892 patients were eligible for analysis. Preoperative US of the axilla was performed in 856/892 (96%) patients, while 36/892 patients (4%) did not undergo US of the axilla. We have found out that upfront ALND due to positive US-FNAB was performed in 91/856 (10.6%) patients. 116/856 patients (13.6%) had tumours in inner quadrants and maximal mammographic tumour size ≤ 2 cm. Among them only 1/116 (0.9%) proceeded directly to ALND due to positive US-FNAB.The final pathology of those who underwent upfront ALND due to positive US-FNAB showed low axillary tumour burden not meeting the indications for ALND in 13/91 (14.3%) patients.Among patients without preoperative axillary US, only 1/36 (2.8%) met the indications for ALND.ConclusionOur results showed that performing US of the axilla is not justified in screen detected breast cancer patients.     

How useful is preoperative imaging for tumor,node, metastasis (TNM) staging of gastric cancer? A meta-analysis

Background

Surgery is the fundamental curative option for gastric cancer patients. Imaging scans are routinely prescribed in an attempt to stage the disease prior to surgery. Consequently, the correlation between radiology exams and pathology is crucial for appropriate treatment planning.

Methods

Systematic searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from January 1, 1998 to December 1, 2009. We calculated the accuracy, overstaging rate, understaging rate, Kappa statistic, sensitivity, and specificity for abdominal ultrasound (AUS), computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) with respect to the gold standard (pathology). We also compared the performance of CT by detector number and image type. A meta-analysis was performed.

Results

For pre-operative T staging MRI scans had better performance accuracy than CT and AUS; CT scanners using ≥4 detectors and multi-planar reformatted (MPR) images had higher staging performances than scanners with <4 detectors and axial images only. For pre-operative N staging PET had the lowest sensitivity, but the highest specificity among modalities; CT performance did not significantly differ by detector number or addition of MPR images. For pre-operative M staging performance did not significantly differ by modality, detector number, or MPR images.

Conclusions

The agreement between pre-operative TNM staging by imaging scans and post-operative staging by pathology is not perfect and may affect treatment decisions. Operator dependence and heterogeneity of data may account for the variations in staging performance. Physicians should consider this discrepancy when creating their treatment plans.

     

How useful is preoperative imaging for tumor,node, metastasis (TNM) staging of gastric cancer? A meta-analysis

Background

Surgery is the fundamental curative option for gastric cancer patients. Imaging scans are routinely prescribed in an attempt to stage the disease prior to surgery. Consequently, the correlation between radiology exams and pathology is crucial for appropriate treatment planning.

Methods

Systematic searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from January 1, 1998 to December 1, 2009. We calculated the accuracy, overstaging rate, understaging rate, Kappa statistic, sensitivity, and specificity for abdominal ultrasound (AUS), computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) with respect to the gold standard (pathology). We also compared the performance of CT by detector number and image type. A meta-analysis was performed.

Results

For pre-operative T staging MRI scans had better performance accuracy than CT and AUS; CT scanners using ≥4 detectors and multi-planar reformatted (MPR) images had higher staging performances than scanners with <4 detectors and axial images only. For pre-operative N staging PET had the lowest sensitivity, but the highest specificity among modalities; CT performance did not significantly differ by detector number or addition of MPR images. For pre-operative M staging performance did not significantly differ by modality, detector number, or MPR images.

Conclusions

The agreement between pre-operative TNM staging by imaging scans and post-operative staging by pathology is not perfect and may affect treatment decisions. Operator dependence and heterogeneity of data may account for the variations in staging performance. Physicians should consider this discrepancy when creating their treatment plans.

     

Neoadjuvant chemotherapy prior to preoperative chemoradiation or radiation in rectal cancer: should we be more cautious?

Neoadjuvant chemotherapy (NACT) is a term originally used to describe the administration of chemotherapy preoperatively before surgery. The original rationale for administering NACT or so-called induction chemotherapy to shrink or downstage a locally advanced tumour, and thereby facilitate more effective local treatment with surgery or radiotherapy, has been extended with the introduction of more effective combinations of chemotherapy to include reducing the risks of metastatic disease. It seems logical that survival could be lengthened, or organ preservation rates increased in resectable tumours by NACT. In rectal cancer NACT is being increasingly used in locally advanced and nonmetastatic unresectable tumours. Randomised studies in advanced colorectal cancer show high response rates to combination cytotoxic therapy. This evidence of efficacy coupled with the introduction of novel molecular targeted therapies (such as Bevacizumab and Cetuximab), and long waiting times for radiotherapy have rekindled an interest in delivering NACT in locally advanced rectal cancer. In contrast, this enthusiasm is currently waning in other sites such as head and neck and nasopharynx cancer where traditionally NACT has been used. So, is NACT in rectal cancer a real advance or just history repeating itself? In this review, we aimed to explore the advantages and disadvantages of the separate approaches of neoadjuvant, concurrent and consolidation chemotherapy in locally advanced rectal cancer, drawing on theoretical principles, preclinical studies and clinical experience both in rectal cancer and other disease sites. Neoadjuvant chemotherapy may improve outcome in terms of disease-free or overall survival in selected groups in some disease sites, but this strategy has not been shown to be associated with better outcomes than postoperative adjuvant chemotherapy. In particular, there is insufficient data in rectal cancer. The evidence for benefit is strongest when NACT is administered before surgical resection. In contrast, the data in favour of NACT before radiation or chemoradiation (CRT) is inconclusive, despite the suggestion that response to induction chemotherapy can predict response to subsequent radiotherapy. The observation that spectacular responses to chemotherapy before radical radiotherapy did not result in improved survival, was noted 25 years ago. However, multiple trials in head and neck cancer, nasopharyngeal cancer, non-small-cell lung cancer, small-cell lung cancer and cervical cancer do not support the routine use of NACT either as an alternative, or as additional benefit to CRT. The addition of NACT does not appear to enhance local control over concurrent CRT or radiotherapy alone. Neoadjuvant chemotherapy before CRT or radiation should be used with caution, and only in the context of clinical trials. The evidence base suggests that concurrent CRT with early positioning of radiotherapy appears the best option for patients with locally advanced rectal cancer and in all disease sites where radiation is the primary local therapy.     

How does preoperative radiotherapy affect the rate of sphincter-sparing surgery in rectal cancer?

The use of preoperative radiotherapy has resulted in significant downstaging and downsizing of tumor, this in turn facilitated resections permitting sphincter preservation and coloanal anastomosis for patients who would otherwise have not been candidates for this type of surgery as concluded by some small studies. On the other hand, other clinical trials have shown that the effect of radiotherapy on the rate of sphincter preservation is still not clear. Moreover, different modes of radiotherapy have been tested on the rate of sphincter preservation such as pelvic irradiation with or without combination of chemotherapy, short or conventional course radiotherapy, and preoperative or postoperative radiotherapy with different timing intervals of surgery. Unfortunately, these trials didn't clearly answer the question of radiotherapy benefit for the sake of sphincter preserving of rectal cancer patients and the question remained hotly debated.     

Neoadjuvant chemotherapy in MRI-staged high-risk rectal cancer in addition to or as an alternative to preoperative chemoradiation?

Background For patients with resectable rectal cancer chemoradiation (CRT) or short-course preoperative radiotherapy (SCPRT) reduces locoregional failure, without extending disease-free survival (DFS) or overall survival (OS). Compliance to postoperative adjuvant chemotherapy is poor. Neoadjuvant chemotherapy (NACT) offers an alternative strategy. Methods A systematic computerised database search identified studies exploring NACT alone or NACT preceding/succeeding radiation. The primary outcome measure was pathological complete response (pCR). Secondary outcome measures included acute toxicity, surgical morbidity, circumferential resection margin, locoregional failure, DFS and OS. Results Four case reports, 12 phase I/II studies, 4 randomised phase II and one randomised phase III study evaluated chemotherapy before CRT. Four prospective studies reviewed chemotherapy after CRT. Three phase II studies investigated chemotherapy using FOLFOX plus bevacizumab without radiotherapy. In 24 studies of 1271 patients, pCR varied from 7% to 36%, but with no impact on metastatic disease. Conclusions NACT before CRT delivers does not compromise CRT but has not increased pCR rates, R0 resection rate, improved DFS or reduced metastases. NACT following CRT is an interesting strategy, and the utility of NACT alone could be explored compared with SCPRT or CRT in selected patients with rectal cancer where the impact of radiotherapy on DFS and OS is marginal.     

Cetuximab in preoperative treatment of rectal cancer – term outcome of the XERT trial

Background

Preoperative capecitabine-based chemoradiotherapy (CRT) is feasible for the treatment of resectable locally advanced rectal cancer (LARC). To try to improve efficacy, we conducted a phase II study in which the epidermal growth factor receptor-targeting monoclonal antibody cetuximab was added to capecitabine-based CRT. The results for long-term survival and for an analysis investigating the relationship between survival and patient and disease characteristics, including tumour KRAS mutation status, and surgery type, are presented.

Patients and methods.

Patients with resectable LARC received capecitabine (1250 mg/m² twice daily, orally) for 2 weeks followed by cetuximab alone (400 mg/m² for 1 week) and then with CRT (250 mg/m²/week) comprising capecitabine (825 mg/m² twice daily) and radiotherapy to the small pelvis (45 Gy in 25 1.8-Gy fractions), five days a week for five weeks. Surgery was conducted six weeks following CRT, with post-operative chemotherapy with capecitabine (1250 mg/m² twice daily for 14 days every 21 days) three weeks later.

Results

Forty-seven patients were enrolled and 37 underwent treatment. Twenty-eight of the patients (75.7%) had T3N+ disease. Thirty-six patients were evaluable for efficacy. The median follow-up time was 39.0 months (range 5.0--87.0). The three-year local control, disease-free survival, relapse-free survival and overall survival rates were 96.9% (95% CI 90.0--100), 72.2% (57.5--86.9), 74.3% (95% CI 59.8--88.8) and 68.1% (95% CI 36.7--99.4), respectively. There was no significant association between survival and gender, age, tumour location in the rectum, type of surgery, pathological T or N status, tumour regression grade or tumour KRAS mutation status, although sample sizes were small.

Conclusions

Preoperative cetuximab plus capecitabine-based CRT was feasible in patients with resectable LARC and was associated with an impressive three-year local control rate. The use of tumour KRAS mutation status as a biomarker for the efficacy of cetuximab-based regimens in this setting requires further investigation.