Complete clinical response after neoadjuvant chemoradiation for distal rectal cancer

Impact of Sarcopenia on Treatment Outcomes and Toxicity in Locally Advanced Rectal Cancer

Background and Objectives: Sarcopenia, a condition characterized by muscle mass loss, is prevalent in up to 68% of rectal cancer patients and has been described as a negative prognostic factor, impacting overall survival and tumor response. While there are extensive data on rectal cancer globally, only a handful of studies have evaluated the role of sarcopenia in locally advanced rectal cancer (LARC). Our study aimed to investigate the relationship between sarcopenia, overall response rate, and toxicity in patients who underwent total neoadjuvant treatment (TNT) for LARC. Materials and Methods: We performed a retrospective study of patients with rectal cancer treated with TNT and surgery with curative intent between 2021 and 2023 at Prof. Dr. Ion Chiricuta Institute of Oncology, Cluj-Napoca. Sarcopenia was assessed on MRI images by measuring the psoas muscle area (PMA) at the level of the L4 vertebra before and after neoadjuvant therapy. The primary endpoints were the overall complete response rate (oCR) and acute toxicity. Results: This study included 50 patients with LARC. The oCR rate was 18% and was significantly associated with post-treatment sarcopenia (OR 0.08, p = 0.043). Patients who did not achieve a clinical or pathologic complete response had, on average, an 8% muscle loss during neoadjuvant therapy (p = 0.022). Cystitis and thrombocytopenia were significantly associated with post-treatment sarcopenia (p = 0.05 and p = 0.049). Conclusions: Sarcopenia and loss of psoas muscle during neoadjuvant therapy were negatively associated with tumor response in locally advanced rectal cancer. Thrombocytopenia and cystitis are more frequent in sarcopenic than non-sarcopenic patients undergoing neoadjuvant chemoradiation for rectal cancer.

Watch & wait - Post neoadjuvant imaging for rectal cancer

Rectal cancer management has evolved over the past decade with the emergence of total neoadjuvant therapy (TNT). For select patients who achieve a clinical complete response following TNT, organ preservation by means of the watch-and-wait (WW) strategy is an increasingly adopted alternative that preserves rectal function and quality of life without compromising oncologic outcomes. Recently, published 5-year results from the OPRA trial demonstrated that organ preservation can be achieved in approximately half of patients managed with the WW strategy, with most local regrowth events occurring within two years. Considering the potential for local regrowth, the implementation of the WW strategy mandates rigorous clinical and radiographic surveillance. Magnetic resonance imaging (MRI) serves as the conventional imaging modality for local staging and surveillance of rectal cancer given its excellent soft-tissue resolution. This review will discuss the current evidence for the WW strategy and the role of restaging rectal MRI in determining patient eligibility for this strategy. Restaging rectal MRI acquisition parameters and treatment response assessment, including important factors to assess, pitfalls, and classification systems, will be discussed in the context of the WW strategy.

MRI-based parameters and clinical risk factors to predict lymph node metastasis in patients with ypT0 rectal cancer after neoadjuvant chemoradiotherapy

BACKGROUNDS

The aim of this study was to assess the significant risk factors that predict lymph node metastasis in ypT0 patients with locally advanced rectal cancer following chemoradiotherapy (CRT). Additionally, the study aimed to identify high-risk groups who would not be suitable candidates for a rectal-preserving strategy, despite achieving a complete tumour response.

METHODS

Between 2013 and 2021, 226 ypT0 patients with stages II/III rectal cancer underwent CRT and radical surgery were enrolled. Two groups of patients were evaluated: those with lymph nodes metastasis and those without. The selection of variables for multivariable logistic regression was conducted through bivariate logistic regression analysis. Furthermore, the determination of optimal cutoff values for risk factors was achieved using ROC curve analysis.

RESULTS

Nearly 8% (18/226) of patients with ypT0 had positive lymph nodes (LN) on final pathology. Four variables resulted as being independent factors of LN metastasis: pre-CRT tumour movability (OR = 8.618, P = 0.003), pre-CRT maximal LN size (OR = 28.474, P = 0.004), post-CRT tumour vertical length (OR = 1.492, P = 0.050), post-CRT anaemia (OR = 10.288, P = 0.001). The optimal cutoff point of pre-CRT maximal LN size and post-CRT tumour vertical length was 7.50 mm and 3.05 cm, respectively.

CONCLUSION

The prevalence of lymph node metastasis remains at 8% among patients who achieve pathological complete regression of the primary tumour. In instances where patients are considered appropriate candidates for a rectal-preserving strategy after clinical complete remission, careful consideration should be given to the selection of this strategy if specific risk factors are present. These risk factors encompass a maximal LN size surpassing 7.50 mm prior to CRT, a fixed tumour prior to CRT, a tumour vertical length exceeding 3.05 cm after CRT, and the existence of anaemia subsequent to CRT.

Whether the watch-and-wait strategy has application value for rectal cancer with clinical complete response after neoadjuvant chemoradiotherapy? A network meta-analysis

The aim was to evaluate the efficacy and safety between the watch-and-wait strategy (WW), radical surgery (RS), and local excision (LE) for rectal cancer with clinical complete response (cCR) after neoadjuvant radiotherapy (nCRT). We searched MEDLINE, EMBASE, the Cochrane Library, and clinical trials to compare WW with RS and LE for patients with cCR until March 2023 and collected the following data: local recurrence (LR), distant metastasis (DM), cancer-related death (CRD), overall survival (OS), and disease-free survival (DFS). In total, 2240 patients from 21 studies were included. Pairwise meta-analysis revealed no statistically significant differences between the three groups in terms of CRD and 2-, 3-, and 5-year OS (P < 0.05). The RS group was significantly better than the WW group in terms of the LR rate (odds ratio [OR] = 0.12, 95 % confidence interval [CI]: 0.06-0.21, P < 0.001, I2 = 0 %], 3-year DFS (OR = 1.56, 95 % CI: 1.10-2.21, P = 0.01, I2 = 38 %), and 5-year DFS (OR = 2.30, 95 % CI: 1.53-3.46, P < 0.001, I2 = 34 %). The results of network meta-analysis were also similar. After sensitivity analysis, the 5-year OS of the RS group was significantly better than that of the WW group (OR = 2.77, 95 % CI: 1.28-6.00, P = 0.009, I2 = 33 %). Nevertheless, neither regression analysis nor subgroup analysis provided meaningful results. However, the cumulative meta-analysis of LR, DM, and 3- and 5-year DFS revealed significant turning points (P < 0.05). Our meta-analysis recommends using the WW strategy for patients with cCR having poor underlying conditions and high surgical risk; however, there is a risk of higher LR and worse survival after 3 years.

Endoscopy and MRI for restaging early rectal cancer after neoadjuvant treatment

AIM

Chemoradiotherapy (CRT) has great potential to downstage rectal cancer. Response assessment has been investigated in locally advanced rectal cancer but not in early stage rectal cancer. The aim is to characterize the diagnostic accuracy of endoscopy performed by surgical endoscopists compared to (diffusion-weighted, DWI) MRI only and a multimodal approach combining (DWI-)MRI and endoscopic information both analysed by an abdominal radiologist for response assessment in early rectal cancer after neoadjuvant CRT.

MATERIALS AND METHODS

Patients treated with neoadjuvant CRT for early distal rectal cancer (cT1-3 N0) followed by transanal endoscopic microsurgery were included. Three separate reassessment groups were analysed for response assessment using endoscopic evaluation alone versus (DWI-)MRI alone versus the combination of endoscopy with (DWI-)MRI with a focus on sensitivity and specificity and analysis using receiver operating characteristic curves.

RESULTS

Three cohorts (N = 36, N = 25 and N = 25, respectively) were analysed for response assessment. Of the endoscopy cohort, 16 of the 36 patients had a complete response. Area under the curve was 0.69 (0.66-0.74; pooled sensitivity 55.3%, pooled specificity 80.0%). Agreement for scoring separate endoscopic features was poor to moderate. Of the (DWI-)MRI cohort, 11 of the 25 patients had a complete response. Area under the curve for (DWI-)MRI alone was 0.55 (sensitivity 72.7%, specificity 42.9%). The areas under the receiver operating characteristic curve improved to 0.68 (sensitivity 90.9%, specificity 75.0%) when (DWI-)MRI was combined with endoscopic information, with 11 out of 25 patients with a complete response. The most accurate response assessment was made by combining endoscopy and (DWI-)MRI with a high negative predictive value (90.9%).

CONCLUSION

Good and complete responders after chemoradiation of early stage rectal cancer can be best assessed using a multimodality approach combining endoscopy and (DWI-)MRI.

Tumor Microenvironment before and after Chemoradiation in Locally Advanced Rectal Cancer: Beyond PD-L1

BACKGROUND

In locally advanced rectal cancer treatment, neoadjuvant concurrent chemoradiation therapy (cCRT) is the standard of care. The tumor microenvironment (TME) is a complex entity comprising of tumor cells, immune cells and surrounding stroma and is closely associated with tumor growth and survival, response to antitumor therapies and also resistance to treatment. We aimed to assess the change in biomarkers associated with TME following standard neoadjuvant cCRT in rectal cancer.

METHODS

We accessed archival tissue from rectal cancer patients treated with neoadjuvant cCRT at Allegheny Health Network (AHN) facilities over the past 14 years. Pre-treatment and post-treatment biopsies were assayed for PD-L1, CD8+ T-cells, CXCL9, TIM-3, IDO-1, IFN-G, IL17RE, LAG-3, and OX40 in 41 patients.

RESULTS

We found statistically significant upregulation in multiple biomarkers namely CD8, IL17RE, LAG3 and OX40 post neoadjuvant cCRT and a trend towards upregulation, although not statistically significant, in biomarkers PD-L1, CXCL9, TIM-3, IDO-1 and IFN-G expression.

CONCLUSIONS

This provides a glimpse into the TME before and after neoadjuvant cCRT. We suggest that the biomarkers noted to be upregulated could be used for designing appropriate clinical trials and development of therapeutic targeted drug therapy in an effort to achieve better response to neoadjuvant therapy, increasing clinical and pathological complete response rates and improved overall outcomes.

The "Immunoscore" in rectal cancer: could we search quality beyond quantity of life?

Because of the function and anatomical environment of the rectum, therapeutic strategies for local advanced rectal cancer (LARC) must deal with two challenging stressors that are a high-risk of local and distal recurrences and a high-risk of poor quality of life (QoL). Over the last three decades, advances in screening tests, therapies, and combined-modality treatment options and strategies have improved the prognosis of patients with LARC. However, owing to the heterogeneous nature of LARC and genetic status, the patient may not respond to a specific therapy and may be at increased risk of side-effects without the life-prolonging benefit. Indeed, each therapy can cause its own side-effects, which may worsen by a combination of treatments resulting in long-term poor QoL. In LARC, QoL has become even more essential with the increasing incidence of rectal cancer in young individuals. Herein, we analyzed the value of the Immunoscore-Biopsy (performed on tumor biopsy at diagnosis) in predicting outcomes, alone or in association with clinical and imaging data, for each therapy used in LARC.

Neoadjuvant Therapy and Surgery in Rectal Adenocarcinoma: Analysis of Patients with Complete Tumor Remission

Introduction: the standard treatment for locally advanced extra-peritoneal rectal adenocarcinoma, consists of neoadjuvant treatment with radiotherapy and chemotherapy followed by total mesorectal excision.

Objective: evaluate, retrospectively, the patients submitted to neoadjuvant therapy and surgery that presents with total remission of the lesion in the anatomopathological examination.

Methods: between 2000 and 2010, 212 patients underwent surgery at the Coloproctology Unit at DMAD at FCM–UNICAMP. They were grouped as: rectosigmoidectomy and colorectal anastomosis (n = 54), rectosigmoidectomy with coloanal anastomosis (n = 41), 114 abdominoperineal resection of the rectum (n = 114) and other (n = 3).

Results: thirty (14.2%) patients (mean age 57.6 years; 60% males) showed complete remission of the rectal lesion. 4 (13.3%) had compromised lymph nodes and/or lymphatic invasion

At follow-up (mean 51.9 months), 4 (13.3%) presented with local recurrence (one patient) or distant metastases (two patients had liver metastasis, one had liver and lung, and one had bone metastasis). The mean survival was 86.7%.

Conclusion: patients with a complete tumor response show ed an increased survival rate, however, the same patients without evidence of residual tumors could develop local recurrence or distant metastases on a later follow-up.

[Preoperative intensity-modulated radiotherapy of rectal cancers: Relevance and modalities]

Preoperative radiotherapy boosted by chemotherapy is a recommended treatment in locally advanced rectal cancers. This treatment is delivered by three dimensional conformal irradiation, which is usually well tolerated but can induce potential toxicity such as rectitis, cystitis and hematologic adverse effects. Intensity-modulated radiotherapy, widely available nowadays, allows optimization of volume covering and sparing of organs at risk such as bladder and bone marrow. This review presents relevant clinical situations and requirements for a beneficial and safe preoperative irradiation of rectal cancers by intensity-modulated technique. This technique is compared to three-dimensional conformal radiotherapy.

Diagnostic performance of magnetic resonance to assess treatment response after neoadjuvant therapy in patients with locally advanced rectal cancer

PURPOSE

Our study aimed to evaluate the diagnostic performance of rectal magnetic resonance imaging (MRI) for local restaging in patients with non-metastatic locally advanced rectal cancer (LARC) after neoadjuvant chemoradiotherapy (CRT) using surgical histopathology of total mesorectal excision as the reference standard.

METHODS

Ninety-five patients with LARC who underwent rectal MRI after CRT between January 2014 and December 2016 were included. Accuracy, sensitivity, specificity, positive, and negative predictive value for local staging regarding T-stage, N-stage, circumferential resection margin, and MRI tumor regression grade (ymriTRG) were calculated, and inter-test agreements were assessed.

RESULTS

22/95 (23.2%) patients had radiological complete response (rCR), whereas 20/95 (21.1%) had pathological complete response (pCR). Among the patients with pCR, 11/20 (55%) had rCR. Fair agreement was demonstrated between ymriTRG and pathological TRG (ypTRG) (κ = 0.255). The sensitivity and specificity for detection of pCR were 61.1% (95% CI 35.7-82.7) and 89.6% (95% CI 80.6-95.4). For the detection of ypTRG grades 1 and 2, the corresponding values were 67.2% (95% CI 54.3-78.4) and 51.6 (95% CI 33.1-69.8). The accuracy of ymriTRG was 24.2% (95% CI 15.6-32.8). Inter-test agreement in TRG between MRI and pathology was overall fair (κ = 0.255) and slight (κ = 0.179), if TRG 1 + 2.

CONCLUSION

Qualitative assessment on MRI for diagnosing pCR showed moderate sensitivity and high specificity, whereas the diagnosis of TRG had moderate sensitivity and low specificity with slight to fair inter-test agreement when compared with pathological specimens.

Effect of Akt activation and experimental pharmacological inhibition on responses to neoadjuvant chemoradiotherapy in rectal cancer

BACKGROUND

Neoadjuvant chemoradiotherapy (CRT) is one of the preferred initial treatment strategies for locally advanced rectal cancer. Responses are variable, and most patients still require surgery. The aim of this study was to identify molecular mechanisms determining poor response to CRT.

METHODS

Global gene expression and pathway enrichment were assessed in pretreatment biopsies from patients with non-metastatic cT2-4 N0-2 rectal cancer within 7 cm of the anal verge. Downstream Akt activation was assessed in an independent set of pretreatment biopsies and in colorectal cancer cell lines using immunohistochemistry and western blot respectively. The radiosensitizing effects of the Akt inhibitor MK2206 were assessed using clonogenic assays and xenografts in immunodeficient mice.

RESULTS

A total of 350 differentially expressed genes were identified, of which 123 were upregulated and 199 downregulated in tumours from poor responders. Mitochondrial oxidative phosphorylation (P < 0·001) and phosphatidylinositol signalling pathways (P < 0·050) were identified as significantly enriched pathways among the set of differentially expressed genes. Deregulation of both pathways is known to result in Akt activation, and high immunoexpression of phosphorylated Akt S473 was observed among patients with a poor histological response (tumour regression grade 0-2) to CRT (75 per cent versus 48 per cent in those with a good or complete response; P = 0·016). Akt activation was also confirmed in the radioresistant cell line SW480, and a 50 per cent improvement in sensitivity to CRT was observed in vitro and in vivo when SW480 cells were exposed to the Akt inhibitor MK2206 in combination with radiation and 5-fluorouracil.

CONCLUSION

Akt activation is a key event in the response to CRT. Pharmacological inhibition of Akt activation may enhance the effects of CRT. Surgical relevance Organ preservation is an attractive alternative in rectal cancer management following neoadjuvant chemoradiotherapy (CRT) to avoid the morbidity of radical surgery. Molecular steps associated with tumour response to CRT may provide a useful tool for the identification of patients who are candidates for no immediate surgery. In this study, tumours resistant to CRT were more likely to have activation of specific genetic pathways that result in phosphorylated Akt (pAkt) activation. Pretreatment biopsy tissues with high immunoexpression of pAkt were more likely to exhibit a poor histological response to CRT. In addition, the introduction of a pAkt inhibitor to cancer cell lines in vitro and in vivo led to a significant improvement in sensitivity to CRT. Identification of pAkt-activated tumours may thus allow the identification of poor responders to CRT. In addition, the concomitant use of pAkt inhibitors to increase sensitivity to CRT in patients with rectal cancer may constitute an interesting strategy for increasing the chance of a complete response to treatment and organ preservation.

Proteomic profiling of rectal cancer reveals acid ceramidase is implicated in radiation response

BACKGROUND

Neoadjuvant chemoradiotherapy (CRT) is used in locally advanced rectal cancer when tumours threaten the circumferential resection margin, with varying response to treatment. This experimental study aimed to identify significantly differentially expressed proteins between patients responding and not responding to CRT, and to validate any proteins of interest.

METHODS

Mass spectrometry (with isobaric tagging for relative quantification) analysis of rectal cancers pre- and post-CRT, and at resection. Validation of proteins of interest was performed by assessing tissue microarray (TMA) immunohistochemistry expression in a further 111 patients with rectal cancer.

RESULTS

Proteomic data are available via ProteomeXchange with identifier PXD008436. Reduced abundance of contributing peptide ions for acid ceramidase (AC) (log fold change -1.526, p = 1.17E-02) was observed in CRT responders. Differential expression of AC was confirmed upon analysis of the TMAs. Cancer site expression of AC in stromal cells from post-CRT resection specimens was observed to be relatively low in pathological complete response (p = 0.003), and relatively high with no response to CRT (p = 0.017).

CONCLUSION

AC may be implicated in the response of rectal cancer to CRT. We propose its further assessment as a novel potential biomarker and therapeutic target.

SIGNIFICANCE

There is a need for biomarkers to guide the use of chemoradiotherapy in rectal cancer, as none are in routine clinical use. We have determined acid ceramidase may have a role in radiation response, based on novel proteomic profiling and validation in a wider dataset using tissue microarrays. The ability to predict or improve response would positively select those patients who will derive benefit, prevent delays in the local and systemic management of disease in non-responders, and reduce morbidity associated with chemoradiotherapy.

Wait-and-see treatment strategies for rectal cancer patients with clinical complete response after neoadjuvant chemoradiotherapy: a systematic review and meta-analysis

Wait-and-see treatment strategies may benefit rectal cancer patients who achieve a clinical complete response (cCR) after neoadjuvant chemoradiotherapy (NCRT). In this study, we analyzed data from 9 eligible trials to compare the oncologic outcomes of 251 rectal cancer patients achieving a cCR through nonsurgical management approaches with the outcomes of 344 patients achieving a pathologic complete response (pCR) through radical surgery. The two patient groups did not differ in distant metastasis rates or disease-free and overall survival, but the nonsurgical group had a higher risk of 1, 2, 3, and 5-year local recurrence. Hence, we concluded that for rectal cancer patients achieving a cCR after NCRT, a wait-and-see strategy with strict selection criteria, an appropriate follow-up schedule, and salvage treatments achieved outcomes at least as good as radical surgery. Long-term randomized and controlled trials with more uniform inclusion criteria and standardized follow-up schedules will help clarify the risks and benefits of wait-and-see treatment strategies for these patients.

Potentiating the effects of radiotherapy in rectal cancer: the role of aspirin, statins and metformin as adjuncts to therapy

BACKGROUND

Complete tumour response (pCR) to neo-adjuvant chemo-radiotherapy for rectal cancer is associated with a reduction in local recurrence and improved disease-free and overall survival, but is achieved in only 20-30% of patients. Drug repurposing for anti-cancer treatments is gaining momentum, but the potential of such drugs as adjuncts, to increase tumour response to chemo-radiotherapy in rectal cancer, is only just beginning to be recognised.

METHODS

A systematic literature search was conducted and all studies investigating the use of drugs to enhance response to neo-adjuvant radiation in rectal cancer were included. 2137 studies were identified and following review 12 studies were extracted for full text review, 9 studies were included in the final analysis.

RESULTS

The use of statins or aspirin during neo-adjuvant therapy was associated with a significantly higher rate of tumour downstaging. Statins were identified as a significant predictor of pCR and aspirin users had a greater 5-year progression-free survival and overall survival. Metformin use was associated with a significantly higher overall and disease-free survival, in a subset of diabetic patients.

CONCLUSIONS

Aspirin, metformin and statins are associated with increased downstaging of rectal tumours and thus may have a role as adjuncts to neoadjuvant treatment, highlighting a clear need for prospective randomised controlled trials to determine their true impact on tumour response and overall survival.

Recent surgical advances in colorectal cancer excision: toward optimal outcomes

Colorectal cancer is the third most common cancer affecting both males and females in the western world. Despite all the developments in the current treatment of colorectal cancer, it is still continuing to be an important factor of patient morbidity and mortality worldwide. Surgery is the mainstay of treatment for colorectal cancer. Over the last decade, there have been major changes and developments in the surgical treatment. Understanding the importance of the anatomy, technological advances in minimally invasive surgery and effects of chemoradiotherapy have changed the approaches to colorectal cancer treatment. Today, novel treatment strategies must be targeted not only minimally invasive approaches, but also aiming to increase patients’ quality of life without compromising the oncological principles.

The role of MRI with diffusion-weighted imaging in restaging rectal cancers after neoadjuvant chemoradiotherapy

Background: It is challenging to restage rectal cancer at MRI, in patients who have had neoadjuvant chemoradiotherapy.Objective: To investigate the accuracy of MRI with diffusion-weighted imaging (DWI) in the restaging of rectal cancer.Materials and methods: Pre- and post-neoadjuvant chemoradiotherapy MRI examinations of 35 patients diagnosed with locally advanced rectal cancer were evaluated and subsequently compared with post-operative pathology results.Results: The accuracy of MRI with DWI to determine the T-stage status was calculated as 54.28%. Kappa statistics revealed poor concordance with pathology results, with a κ value of 0.212 ± 0.114 (p = 0.028). The apparent diffusion coefficient (ADC) values measured after the neoadjuvant chemotherapy revealed a significant increase when compared with pre-treatment ADC values (p < 0.000001). MRI accuracy rate for lymph node involvement was calculated as 57.14% with a κ value of 0.001 (p = 0.989). MRI had 80% sensitivity and 100% specificity in determining mesorectal fascia involvement, with a calculated positive predictive value of 100% and a calculated negative predictive value of 96%. The accuracy of MRI in overall staging according to the TNM staging system was 28%.Conclusion: The accuracy of MRI in restaging rectal cancer is not yet sufficient and is not on par with the accuracy of MRI in the primary staging of the disease. This is attributed to post-treatment changes. Adding DWI to the protocol is promising, but more expanded data are required.

Colorectal cancer outcomes in patients aged over 85 years

INTRODUCTION

The prevalence of colorectal cancer is increasing in the elderly. We examined the treatment and outcomes in our institution of patients aged over 85 years with proven colorectal adenocarcinoma.

METHODS

One hundred and five patients were identified and stratified by treatment received: curative surgery (CS), other treatments (OT) or best supportive care (BSC). Data on demographics, staging, treatment and survival was collected and analysed.

RESULTS

Forty two patients received CS, 36 OT and 27 BSC. While the treated groups (CS and OT) were similar in terms of age (p=0.35) and staging (p=0.16), BSC patients were significantly older and had higher stage disease (p<0.01). Survival was significantly poorer among BSC patients, at a mean of 9.7 months (95% confidence interval [CI] 4.7-14.7) versus 41.6 months (95% CI 32.5-50.7) and OT 27.3 months (95% CI 20.4-34.1) for the CS and OT groups (p<0.001). There was no significant survival difference between CS and OT groups within 2 years of treatment (p=0.12). Thereafter, OT patients had a very similar 5-year survival to that of the BSC group, at 13% versus 43% in CS patients (p<0.001).

CONCLUSIONS

These data suggest that, up to 2 years following treatment, the risks of resectional surgery for colorectal cancer may neutralise any benefit. However, those that survive beyond this period show improvements. The challenge of improving patient selection is most acute in the growing ageing population, and highlights the current focus on presenting all treatment options to 'a reasonable patient'.

Predicting pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer: a systematic review

AIM

Approximately 20% of patients treated with neoadjuvant chemoradiotherapy (nCRT) for locally advanced rectal cancer achieve a pathological complete response (pCR) while the remainder derive the benefit of improved local control and downstaging and a small proportion show a minimal response. The ability to predict which patients will benefit would allow for improved patient stratification directing therapy to those who are likely to achieve a good response, thereby avoiding ineffective treatment in those unlikely to benefit.

METHOD

A systematic review of the English language literature was conducted to identify pathological factors, imaging modalities and molecular factors that predict pCR following chemoradiotherapy. PubMed, MEDLINE and Cochrane Database searches were conducted with the following keywords and MeSH search terms: 'rectal neoplasm', 'response', 'neoadjuvant', 'preoperative chemoradiation', 'tumor response'. After review of title and abstracts, 85 articles addressing the prediction of pCR were selected.

RESULTS

Clear methods to predict pCR before chemoradiotherapy have not been defined. Clinical and radiological features of the primary cancer have limited ability to predict response. Molecular profiling holds the greatest potential to predict pCR but adoption of this technology will require greater concordance between cohorts for the biomarkers currently under investigation.

CONCLUSION

At present no robust markers of the prediction of pCR have been identified and the topic remains an area for future research. This review critically evaluates existing literature providing an overview of the methods currently available to predict pCR to nCRT for locally advanced rectal cancer. The review also provides a comprehensive comparison of the accuracy of each modality.

Assessing pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer: a systematic review

AIM

Pathological complete response to neoadjuvant chemoradiotherapy is found in 20% of patients with rectal cancer undergoing long-course chemoradiotherapy. Some authors have suggested that these patients do not need to undergo surgery and can be managed with careful follow-up, with surgery only used in the event of clinical failure. Widespread adoption of this regimen is limited by the accuracy of methods to confirm a pathological complete response (pCR).

METHOD

A systematic search of PubMed, Medline and Cochrane databases was conducted to identify clinical, histological and radiological features in those patients with rectal cancer who achieved a pCR following chemoradiotherapy. Searches were conducted with the following keywords and MeSH search terms: 'rectal neoplasm', 'response', 'neoadjuvant', 'preoperative chemoradiation' and 'tumour response'. After review of title and abstracts, 89 articles addressing the assessment of pCR were identified.

RESULTS

Histology and clinical assessment are the most effective methods of assessment of pCR, with histology considered the gold standard. Clinical assessment is limited to low rectal tumours and is open to significant inter-rater variability, while histological examination requires a surgical specimen. Diffusion-weighted MRI and (18) F-fluorodeoxyglucose positron emission tomography/CT demonstrate the greatest potential for the assessment of pCR, but both modalities have limited accuracy.

CONCLUSION

Determination of a pCR is crucial if a nonoperative approach is to be undertaken proactively. Various methods are available, but currently they lack sufficient sensitivity and specificity to define management. This is likely to be an area of further research in the future.

Surgeon perspectives on the use and effects of neoadjuvant chemoradiation in the treatment of rectal cancer: a comprehensive review of the literature

BACKGROUND

Despite screening initiatives, rectal cancer remains one of the most prevalent malignancies diagnosed in patients worldwide with a high mortality. The introduction of neoadjuvant therapy has resulted in a paradigm shift in the treatment and outcomes of rectal cancer. Surgeons play an intricate role in the pre-operative, operative, and post-operative management of these patients.

PURPOSE

The purpose of this comprehensive literature review was to summarize the evolution of the use chemotherapy and radiation and the process of differentiation into specific neoadjuvant chemoradiation protocols in the treatment of locally advanced rectal cancer. This will provide a concise summary for practicing surgeons of the current evidence for neoadjuvant chemoradiation as well as the various implications of therapy on operative outcomes.

CONCLUSION

The initial benefit of adjuvant therapy in the treatment of rectal cancer patients became evident with prospective studies demonstrating improvements in various oncologic survival outcomes. Due to the improved compliance and reduced toxicity, as well as the potential for tumor down-staging and sphincter preservation, neoadjuvant approaches became the preferred method of administering chemotherapy and radiation. Furthermore, a subgroup of patients has been shown to present with complete clinical response to neoadjuvant therapy. This has resulted in the development of the non-operative "watch and wait" approach, which has initiated discussions on changing the interval from the completion of neoadjuvant therapy to surgical resection. The continued development of the multidisciplinary approach will only further improve our ability to provide patients with the best possible oncologic outcomes.

Normalization of CEA Levels Post-Neoadjuvant Therapy is a Strong Predictor of Pathologic Complete Response in Rectal Cancer

BACKGROUND

Recent attention has been focused on the relationship between carcinoembryonic antigen (CEA) and pathological complete response (pCR), without consensus regarding its predictive value. This study aims to examine the association between CEA and pCR.

METHODS

We conducted a retrospective review of a prospectively maintained database of all patients who underwent primary rectal cancer resection after neo-adjuvant chemoradiotherapy (nCRT). Patients were divided into two groups, pCR or no-pCR, based on final pathology. CEA levels were measured at the initial visit with the surgeon/oncologist and post-completion of nCRT.

RESULTS

One hundred and forty-one patients underwent primary rectal cancer resections after nCRT. Nineteen patients (13.5 %) achieved pCR, while 122 (86.5 %) had no-pCR. Pre-nCRT CEA levels were not significantly different between groups (2.75 vs 4.5 μg/L, p = 0.65). However, post-nCRT CEA levels were significantly lower in patients with pCR (1.7 vs 2.4 μg/L, p < 0.01). On multivariate logistic regression analyses, low post-nCRT CEA level was an independent predictor of pCR (OR 1.74, CI 1.06, 3.81) and normalization of CEA from an initially elevated level was a highly significant predictor of pCR (OR 64.8, CI 2.53, 18,371).

CONCLUSION

Low post-nCRT CEA is an independent predictor of pCR, and normalization of CEA post-nCRT is a strong predictor of pCR.

Surgery in the era of the 'omics revolution

Background

Surgery is entering a new phase with the revolution in genomic technology. Cheap, mass access to next‐generation sequencing is now allowing the analysis of entire human genomes at the DNA and RNA level. These data sets are being used increasingly to identify the molecular differences that underlie common surgical diseases, and enable them to be stratified for patient benefit.

Methods

This article reviews the recent developments in the molecular biology of colorectal, oesophagogastric and breast cancer.

Results

The review specifically covers developments in genetic predisposition, next‐generation sequencing studies, biomarkers for stratification, prognosis and treatment, and other 'omics technologies such as metabolomics and proteomics.

Conclusion

There are unique opportunities over the next decade to change the management of surgical disease radically, using these technologies. The directions that this may take are highlighted, including future advances such as the 100 000 Genomes Project.

May individualize cancer treatment

Intermediate neoadjuvant radiotherapy for T3 low/middle rectal cancer: postoperative outcomes of a non-controlled clinical trial

Background

The benefits of adjuvant radiotherapy in rectal carcinoma are well known. However, there is still considerable uncertainty about the optimal radiation treatment. There is an ongoing debate about the choice between very short treatments immediately followed by surgical resection and prolonged treatments with delayed surgery. In this paper, we describe an interim analysis of a non-controlled clinical trial in which radiotherapy delivered with intermediate dose/duration was followed by surgery after about 2 weeks to improve local control and survival after curative radiosurgery for cT3 low/middle rectal cancer.

Methods

Preoperative radiotherapy (36 Gy in 3 weeks) was delivered in 248 consecutive patients with cT3NxM0 rectal adenocarcinoma within 10 cm from the anal verge, followed by surgery within the third week after treatment completion.

Results

166 patients (66.94%) underwent anterior resection, 80 patients (32.26%) the Miles' procedure and 2 patients (0.8%) the Hartmann's procedure. Local resectability rate was 99.6%, with 226 curative-intent resections. The overall rate of complications was 27.4%. 5-year oncologic outcomes were evaluated on 223 patients. The median follow-up time was 8.9 years (range 5-17.4 years); local recurrence (LR) rate and distal recurrence (DR) rate after 5 years were 6.28% and 21.97%, respectively. Overall survival was 74.2%; disease free survival was 73.5%; local control was 93.4 % and metastasis-free survival was 82.1%.

Conclusions

preoperative radiotherapy with intermediate dose/duration and interval between radiotherapy and surgery achieves high local control in patients with cT3NxM0 rectal cancer, and high DR rate seems to be the major limitation to improved survival.

Sphincter preservation in distal CT2N0 rectal cancer after preoperative chemoradiotherapy

BACKGROUND

Preoperative chemoradiotherapy is usually not indicated for cT2N0 rectal cancer. Abdominoperineal resection is the standard treatment for distal rectal tumors. The aim of the study was to evaluate the actual sphincter-preservation rate in patients with distal cT2N0 rectal cancer given neoadjuvant chemoradiotherapy.

METHODS

Data were retrospectively collected for all patients who were diagnosed with distal cT2N0 rectal cancer at a tertiary medical center in 2000-2008 and received chemoradiotherapy followed by surgery (5-7 weeks later).

RESULTS

Thirty-three patients (22 male) of median age 65 years (range, 32-88) were identified. Tumor distance from the anal verge ranged from 0 to 5 cm. R0 resection with sphincter preservation was accomplished in 22 patients (66%), with a 22% pathological complete response rate. Median follow-up time was 62 months (range 7-120). There were no local failures. Crude disease-free and overall survival were 82% and 86%, respectively. Factors associated with sphincter preservation were tumor location (OR=0.58, p=0.02, 95% CI=0.37-0.91) and pathological downstaging (OR=7.8, p=0.02, 95% CI=1.35-45.85). Chemoradiotherapy was well tolerated.

CONCLUSION

High rates of sphincter preservation can be achieved after preoperative chemoradiotherapy for distal cT2N0 rectal cancer, with tolerable toxicity, without compromising oncological outcome.

MR imaging for rectal cancer: the role in staging the primary and response to neoadjuvant therapy

Pre-operative staging is an essential aspect of modern rectal cancer management and radiological assessment is central to this process. An ideal radiological assessment should provide sufficient information to reliably guide pre-operative decision-making. Technical advances allow high-resolution imaging to not only provide prognostic information but to define the anatomy, helping the surgeon to anticipate potential pitfalls during the operation. The main imaging modality for local staging of rectal cancer is Magnetic Resonance Imaging (MRI), as it defines the tumour and relevant anatomy providing the most detail on the important prognostic factors that influence treatment choice. In addition, there is an emerging role for MRI in the assessment of the response to neoadjuvant therapy. This article is an evidence-based review of rectal cancer staging focusing on post-treatment assessment of response using MRI. The discussion extends into the implications for reliably assessing response and how this may influence future rectal cancer management.

Tumor response assessment in locally advanced colon cancer after neoadjuvant chemotherapy

BACKGROUND

Preoperative chemotherapy followed by radical surgery is a novel therapeutic approach for locally advanced colon cancer (LACC). Neoadjuvant strategies require highly accurate diagnostic tests for a proper selection of candidate patients, allowing a low risk of overtreatment. This paper assesses the radiological, metabolic and pathological findings induced by preoperative oxaliplatin and fluoropyrimidines-based chemotherapy in LACC.

METHODS

Forty-four consecutive patients with a confirmed diagnosis of LACC who received neoadjuvant chemotherapy and colon surgery were included. All patients were staged at baseline and before surgery. Clinical diagnosis consisted of physical examination, endoscopy with biopsy and computed tomography (CT) scan. In selected cases, a positron emission tomography/CT (PET/CT) scan was also performed. Accuracy and correlations between CT scan findings and pathologic report was assayed for T stage, N stage and TN stage. This study is retrospective in design.

RESULTS

After chemotherapy, a statistical significant tumor volume reduction of 62.5% was achieved by CT-scan (P<0.001; Wilcoxon test) and a 38.9% decrease of standard uptake value (SUVmax) was observed on PET/CT (P=0.004). No progressive disease was reported during neoadjuvant treatment. Accuracy for T and N classification was 62% and 87%, respectively. Accuracy for TN stage was 77%, with 13.6% and 9.1% of the patients being under or overstaged, respectively. Pathologic stage II and III disease was observed in 29/44 (65.9%) and 15/44 (34.1%) of the patients, respectively. Pathologic complete response was achieved in three patients.

CONCLUSIONS

Oxaliplatin/fluorpyrimidine neoadjuvant chemotherapy induces major tumour shrinkage at both the pathological and radiological levels. The CT scan shows a high accuracy and a low overstaged rate in LACC patients treated by means of a neoadjuvant approach.

Current controversies in neoadjuvant chemoradiation of rectal cancer

Total mesorectal excision with preoperative radiation and chemotherapy provide the lowest local recurrence rates for rectal cancer. Timing of surgery after preoperative chemoradiation is being increased to optimize tumor downstaging. In cases of complete clinical response from chemoradiation, permissive observation without resection is being investigated. Significant anorectal dysfunction results from low anterior resection and radiation. Good prognostic tumor characteristics are being investigated with the aim of selecting cases for whom preoperative radiation may be avoided. Preoperative and postoperative radiation provides improved local cancer control for superficial cancers removed by local excision.

How reliable is current imaging in restaging rectal cancer after neoadjuvant therapy?

In patients with advanced rectal cancer, neoadjuvant chemo radiotherapy provides tumor downstaging and downsizing and complete pathological response in up to 30% of cases. After proctectomy complete pathological response is associated with low rates of local recurrence and excellent long term survival. Several authors claim a less invasive surgery or a non operative policy in patients with partial or clinical complete response respectively, however to identify patients with true complete pathological response before surgical resection remains a challenge. Current imaging techniques have been reported to be highly accurate in the primary staging of rectal cancer, however neoadjuvant therapy course produces deep modifications on cancer tissue and on surrounding structures such as overgrowth fibrosis, deep stroma alteration, wall thickness, muscle disarrangement, tumor necrosis, calcification, and inflammatory infiltration. As a result, the same imaging techniques, when used for restaging, are far less accurate. Local tumor extent may be overestimated or underestimated. The diagnostic accuracy of clinical examination, rectal ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography using 18F-fluoro-2’-deoxy-D-glucose ranges between 25% and 75% being less than 60% in most studies, both for rectal wall invasion and for lymph nodes involvement. In particular the ability to predict complete pathological response, in order to tailor the surgical approach, remains low. Due to the radio-induced tissue modifications, combined with imaging technical aspects, low rate accuracy is achieved, making modern imaging techniques still unreliable in restaging rectal cancer after chemo-radiotherapy.

Preliminary outcome of a treatment strategy based on perioperative chemotherapy and surgery in patients with locally advanced colon cancer

AIM

Preoperative chemotherapy followed by radical surgery is an attractive treatment for locally advanced colon cancer (LACC) given the promising results of this approach in other locally advanced tumours. The study evaluates the outcome and treatment-related complications of perioperative oxaliplatin- and capecitabine-based chemotherapy and surgery for clinical Stage III colon cancer.

METHOD

Twenty-two consecutive patients with a CT-staged LACC were included. All were staged at baseline and before surgery. Surgery-related complications and oncological outcome were determined.

RESULTS

Toxicity was manageable, with 19/22 patients completing the planned chemotherapy protocol. The median time from initial diagnosis to surgery was 65.5 days. The median time from the end of chemotherapy to surgery was 22 days. After neoadjuvant treatment, tumour reduction of 69.5% was observed by CT scan and a 59.9% decrease of SUVmax (standard uptake value) was achieved on positron emission tomography/CT. No progressive disease was reported during preoperative chemotherapy and surgery was performed in all 22 patients. Four patients developed postoperative complications. After a median postoperative follow-up of 14.4 months, the actuarial overall and disease-free survival rates were 100 and 90%.

CONCLUSION

Neoadjuvant chemotherapy followed by surgery and chemotherapy for LACC is safe without apparent increase of early and medium-term complications.

[Clinical and oncological results of the pathological complete response in rectal cancer after neoadjuvant treatment]

INTRODUCTION

Neoadjuvant chemo-radiotherapy is the treatment of choice for rectal cancer in order to reduce local recurrence. Patients with a pathological complete response (PCR) have a better prognosis. The aim of this study was to determine the influence of PCR on the oncological outcomes in our patients.

METHODS

All patients with stage ii/iii rectal cancer treated with neoadjuvant chemo-radiotherapy and radical resection between 2007 and 2011 were identified from a prospective database, and grouped based on whether they achieved PCR or not (non-PCR). Clinical, histological and oncological outcome data were compared.

RESULTS

A total of 162 patients were included (62% men), with a mean age of 65 years. In terms of pre-operative TNM staging, 82 patients (50%) were T2, 75 (46%) were T3, and 5 (3%) were T4. Forty-two patients (25%) were N1, and 87 (53%) were N2. Low anterior resection and abdominoperineal resection were performed in 125 (77%) and 25 (15%) patients. Forty-three patients (26.5%) had postoperative morbidity. PCR was achieved in 19 patients (11.7%). After a median follow-up of 26 months, there are no recurrences in the PCR group, and in the non-PCR group, local recurrence was 1.4% (P=.78), and distant metastasis was 8.4% (P=.21). Overall survival (P=.39) and survival free of diseases (P=.23) were better in the PCR group, but the differences were not significant.

CONCLUSION

Patients with pathological complete response have better oncological outcome.

Transanal endoscopic microsurgery for residual rectal cancer (ypT0-2) following neoadjuvant chemoradiation therapy: another word of caution

BACKGROUND

Significant tumor downstaging among patients with rectal cancer following neoadjuvant chemoradiation has raised the issue of offering patients with small residual cancers restricted to the bowel wall an alternative treatment strategy to total mesorectal excision. Transanal endoscopic microsurgery may allow proper primary tumor resection with promising oncological outcomes, less postoperative morbidity, and minimal long-term sexual, urinary, and fecal continence disorders in comparison with radical resection.

OBJECTIVE

The aim of this study was to determine the oncological outcomes of patients with residual rectal cancers restricted to the rectal wall (ypT0-2) following neoadjuvant chemoradiation and transanal endoscopic microsurgery.

DESIGN

This study considered a prospective cohort of patients with residual rectal cancers following neoadjuvant chemoradiation treated by transanal endoscopic microsurgery and no additional systemic therapy.

SETTINGS

This study was a single-institution experience.

PATIENTS

Patients with adenocarcinoma of the rectum located no more than 7 cm from the anal verge and endorectal ultrasound- or magnetic resonance-staged cT2-4N0-2M0 treated by neoadjuvant chemoradiation (50.4-54 Gy and 5-fluorouracil-based chemotherapy) were eligible for the study. Patients with small residual tumors (≤3 cm) radiologically staged ycT0-2N0 were treated by transanal endoscopic microsurgery.

INTERVENTIONS

Transanal endoscopic microsurgery was performed.

MAIN OUTCOME MEASURES

The primary outcome measured was local recurrence.

RESULTS

Of the 27 patients treated by transanal endoscopic microsurgery, 3 had ypT0, 6 had ypT1, and 18 had ypT2 cancers. All patients underwent R0 transanal endoscopic microsurgery excision. Local recurrence was observed in 4 (15%) patients after a median follow-up of 15 months. Only lymphovascular invasion was an independent predictive factor for local failure (p = 0.04). Tumor size, ypT status, T-status downstaging, lateral/radial margins, and tumor regression grade were not predictors of local failure.

LIMITATIONS

This study was limited by the small sample size and limited follow-up.

CONCLUSIONS

A local failure rate of 15% after transanal endoscopic microsurgery for patients with residual rectal cancers restricted to the bowel wall (ypT0-2) may limit the indication of this procedure to highly selected patients as an alternative to standard radical total mesorectal excision.

Long-term outcome following surgery for colorectal cancers in octogenarians: a single institution's experience of 204 patients

BACKGROUND

The incidence of colorectal cancer in elderly patients is likely to increase with an aging population. The aims of this study are to review our experience in the surgical management of octogenarians with colorectal cancers and to identify factors that influence the short-term and long-term outcomes.

METHODS

A retrospective review of all octogenarians who underwent surgery for colorectal cancer from December 2002 to October 2008 was performed.

RESULTS

We identified 204 patients with a median age of 84 years (range, 80-97 years). The majority of patients had an American Society of Anesthesiologists score ≥3 (n = 142, 69.6%) and a Charlson Comorbidity Index of ≤3 (n = 128, 62.7%). Emergency surgery was performed in 83 (40.7%) patients. Left-sided malignancy was seen in 138 patients (67.6%). Most of the patients had either stage II (n = 75, 36.8%) or III (n = 69, 33.8%) diseases. The 30-day mortality rate was 16.2% (n = 33). After multivariate analysis, the independent variables predicting worse perioperative complications and death were age >85 years old, emergency surgery, and Charlson Comorbidity Index >3. The median follow-up for the 171 remaining patients was 27 months (range, 2-92 months). The 30-day readmission rate was 2.9% (n = 5). Thirty-one (21.2%) of 146 patients who survived curative surgery developed recurrent disease. Seventy (34.3%) patients died from various etiologies after their first 30 days postoperatively (60% cancer-specific with median survival of 15 months and 40% noncancer-related with median survival of 14 months). Overall and disease-free survivals were adversely affected in patients with advanced malignancy and in those with severe perioperative complications.

CONCLUSIONS

Surgery for octogenarians with colorectal cancers is associated with significant morbidity and mortality rates which are associated with advanced age, emergency surgery, and Charlson Comorbidity Index >3. Long-term survival is dependent on the stage of the malignancy and the presence of severe perioperative complications.

Critical appraisal of the 'wait and see' approach in rectal cancer for clinical complete responders after chemoradiation

BACKGROUND

Some 10-20 per cent of patients with locally advanced rectal cancer achieve a pathological complete response (pCR) at surgery following preoperative chemoradiation (CRT). Some demonstrate a sustained clinical complete response (cCR), defined as absence of clinically detectable residual tumour after CRT, and do not undergo resection. The aim of this review was to evaluate non-operative treatment of rectal cancer after CRT, and the outcome of patients observed without radical surgery.

METHODS

A systematic computerized search identified 30 publications (9 series, 650 patients) evaluating a non-operative approach after CRT. Original data were extracted and tabulated, and study quality evaluated. The primary outcome measure was cCR. Secondary outcome measures included locoregional failure rate, disease-free survival and overall survival.

RESULTS

The most recent Habr-Gama series reported a low locoregional failure rate of 4·6 per cent, with 5-year overall and disease-free survival rates of 96 and 72 per cent respectively. These findings were supported by a small prospective Dutch study. However, other retrospective series have described higher recurrence rates. All studies were heterogeneous in staging, inclusion criteria, study design and rigour of follow-up after CRT, which might explain the different outcomes. The definition of cCR was inconsistent, with only partial concordance with pCR. The results suggested that patients who are observed, but subsequently fail to sustain a cCR, may fare worse than those who undergo immediate tumour resection.

CONCLUSION

The rationale of a 'wait and see' policy relies mainly on retrospective observations from a single series. Proof of principle in small low rectal cancers, where clinical assessment is easy, should not be extrapolated uncritically to more advanced cancers where nodal involvement is common. Long-term prospective observational studies with more uniform inclusion criteria are required to evaluate the risk versus benefit.

Primary staging and response assessment postchemoradiotherapy in rectal cancer

SUMMARY Initial assessment of newly diagnosed patients with rectal cancer includes clinical examination, colonoscopy, pelvic MRI and CT scan of the thorax, abdomen and pelvis. Radiological staging can objectively evaluate both surgical and biological prognostic features of rectal cancer. MRI has emerged to be the most useful preoperative prognostic staging tool and it can predict the risk of tumor involvement of surgical circumferential resection margin. An agreed definition of favorable tumor response to chemoradiotherapy is controversial. The importance of detecting and assessing good versus poor responders to chemoradiotherapy is of increasing relevance. MRI has been found to be useful in assessing tumor response postchemoradiotherapy, especially the assessment of potential circumferential resection margin and magnetic resonance tumor regression grade. These imaging markers predict survival outcomes for good and poor responders and provide an opportunity for clinicians to offer additional neoadjuvant and adjuvant treatments to reduce local or distance failure for the poor responders.

Long-term outcome of patients with complete pathologic response after neoadjuvant chemoradiation for cT3 rectal cancer: implications for local excision surgical strategies

BACKGROUND

Neoadjuvant chemoradiotherapy (CRT) followed by radical surgery including total mesorectal excision (TME) is standard treatment in patients with locally advanced rectal cancer. Emerging data indicate that patients with complete pathologic response (ypCR) after CRT have favorable outcome, suggesting the possibility of less invasive surgical treatment. We analyzed long-term outcome of cT3 rectal cancer treated by neoadjuvant CRT in relation to ypCR and type of surgery.

METHODS

The study population comprised 139 patients (93 men, 46 women; median age 62 years) with cT3N0-1M0 mid and distal rectal adenocarcinoma treated by CRT and surgery (110 TME and 29 local excision) at our institution between 1996 and 2008. At pathology, ypCR was defined as no residual cancer cells in the primary tumor.

RESULTS

Tumors of 42 patients (30.2%) were classified as ypCR. After a median follow-up of 55.4 months, comparing patients with ypCR to patients with no ypCR, 5-year disease-specific survival was 95.8% versus 78.0% (P = 0.004), and 5-year disease-free survival was 90.1% vs. 64.0% (P = 0.004). In patients with ypCR, no statistically significant outcome difference was observed between TME and local excision. In patients treated by local excision, comparing patients with ypCR to patients with no ypCR, 5-year disease-free survival was 100% vs. 65.5% (P = 0.024), and 5-year local recurrence-free survival was 92.9% vs. 66.7% (P = 0.047).

CONCLUSIONS

With retrospective analysis limitations, our data confirm favorable long-term outcome of cT3 rectal cancer with ypCR after CRT and warrant clinical trials exploring local excision surgical strategies.

Accuracy of endoscopic ultrasound to assess tumor response after neoadjuvant treatment in rectal cancer: can we trust the findings?

BACKGROUND

The finding that some rectal cancers respond to neoadjuvant chemoradiation is broadening new surgical options for the treatment of some of these tumors that, until now, required a total mesorectal excision. Nevertheless, a fine match between clinical and pathological response is required when planning conservative surgical approaches.

OBJECTIVE

This study aims to prospectively validate the use of endoscopic ultrasound as a predictor of clinical and pathological tumor response in patients with locally advanced rectal cancer.

DESIGN

: This is an observational study of a cohort of patients undergoing chemoradiation followed by surgery.

SETTINGS

This study was conducted at a tertiary medical center.

PATIENTS

A total of 235 consecutive patients who underwent chemoradiation followed by surgery at a single institution during a 7-year period were included.

MAIN OUTCOME MEASURES

All tumors were staged and restaged at 4 to 6 weeks after neoadjuvant treatment. Downsizing and downstaging were calculated between the initial and posttreatment measures and correlated to the pathological stage. The accuracy of endoscopic ultrasound to predict response was determined.

RESULTS

Findings after chemoradiation showed T-downstaging in 54 patients (23%) and N-downstaging in 110 (47%). Overstaging occurred in 88 (37%) patients and was more commonly observed than understaging (21 patients; 9%). Related to the pathological report, endoscopic ultrasound correctly matched the T stage in 54% and the N stage in 75% of tumors. Sensitivity, specificity, and positive and negative predictive values to predict nodal involvement were 39%, 91%, 67%, and 76%. Accuracy was not influenced by such factors as age, distance of the tumor from the anal verge, or time to surgery.

LIMITATIONS

This study was limited by the lack of comparison with other imaging methods.

CONCLUSIONS

Endoscopic ultrasound allows prediction of involved lymph nodes in 75% of the cases; however, 1 in 5 patients are missclassified as uN0 after neoadjuvant treatment. In our point of view, this percentage is too high to rely only on this diagnostic modality to support a "wait and see" approach.