Rectal Cancer and Radiation in Colitis.

Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer. When IBD patients develop a rectal cancer, this should be treated with the same oncological principles and guidelines as the general population. Rectal cancer treatment includes surgery, chemotherapy, and radiation therapy (RT). Many IBD patients will require a total proctocolectomy with an ileal-pouch anal anastomosis (IPAA) and others, restoration of intestinal continuity may not be feasible or advisable. The literature is scarce regarding outcomes of IPAA after RT. In the present review, we will summarize the evidence regarding RT toxicity in IBD patients and review surgical strategies and outcomes of IPAA after RT.

Chemoradiation and Local Excision Versus Total Mesorectal Excision for T2N0 Rectal Cancer: Comparison of Short- and Long-Term Outcomes From 2 Prospective Studies.

OBJECTIVE: Compare oncological long-term and short-term outcomes between patients with distal cT2NO rectal cancer treated with chemoradio-therapy and local excision (CRT + LE) and patients treated with total mesorectal excision (TME). SUMMARY BACKGROUND DATA: Previous studies showed that CRT + LE is equivalent to TME in local tumor control and survival for T2N0 rectal cancer. METHODS: Seventy-nine patients with cT2N0 rectal adenocarcinoma treated with CRT + LE in the ACOSOG Z6041 trial were compared to a cohort of 79 patients with pT2N0 tumors treated with upfront TME in the Dutch TME trial. Survival, short-term outcomes, and health-related quality of life (HRQOL) were compared between groups. RESULTS: Three patients (4%) in the CRT + LE group required abdominoperineal resection, compared with 31 (40%) in the TME group. Forty TME patients (51%) required a permanent stoma. CRT-related toxicity occurred in 43% of the CRT + LE patients; however, TME patients had a higher rate of complications requiring reoperation (1 vs 9%; P = 0 .03). Five-year disease-free survival {88.2% [confidence interval (CI), 77.7%-93.9%] vs 88.3% [CI, 78.7%-93.7%]; P = 0.88} and overall survival [90.3% (CI, 80.8%-95.3%) vs 88.4% (CI, 78.9%-93.8%); P = 0 .82] were similar in the 2 groups. Compared to baseline, overall HRQOL decreased in the CRT + LE group and improved in the TME group. In both groups, patients with sphincter preservation had worse HRQOL scores 1 year after surgery. Conclusions: In patients who underwent CRT + LE, oncological outcomes were similar to those of patients who underwent TME, with fewer complications requiring reoperation but significant CRT toxicity. Although overall HRQOL decreased in the CRT + LE group and improved in TME patients, when considering anorectal function, results were worse in both groups.

Operative, long-term and quality of life outcomes after salvage of failed re-do ileal pouch anal anastomosis.

AIM: Approximately 20%-40% of the patients with re-do ileal pouch anal anastomosis (IPAA) experience pouch failure. Salvage surgery can be attempted in this patient group with severe aversion to permanent ileostomy. The literature regarding secondary IPAA revision after re-do IPAA failure is scarce. METHODS: All patients who underwent a secondary IPAA revision after re-do IPAA failure between September 2016 and July 2021 in a single centre were included. Short- and long-term outcomes and quality of life in this patient group are reported. RESULTS: Ten patients who had secondary IPAA revision for re-do IPAA failure were included. All patients had ulcerative colitis. Nine of these patients had pelvic sepsis and one patient had a mechanical issue. Mucosectomy and handsewn anastomosis was performed in nine patients. The existing pouch was salvaged in six patients and four patients had pouch excision and re-creation. Two patients had postoperative pelvic sepsis. Pouch retention rate was 78% in a median of 28 months. None of the patients had short-gut syndrome. The procedure was associated with good quality of life (median Cleveland Global Quality of Life Index 0.8). All patients would undergo the same surgery if needed. CONCLUSION: Secondary IPAA revision after a failed re-do IPAA can be an option in patients with severe aversion to permanent ileostomy if re-do IPAA fails and it is associated with good outcomes. This patient group should be carefully evaluated and referred to specialized centres if required.

Pelvic Pouch Failure: Treatment Options.

Up to 30% of patients with ulcerative colitis (UC) will require surgical management of their disease during their lifetime. An ileal pouch-anal anastomosis (IPAA) is the gold standard of care, giving patients the ability to be free from UC's bowel disease and avoid a permanent ostomy. Despite surgical advancements, a minority of patients will still experience pouch failure which can be debilitating and often require further surgical interventions. Signs and symptoms of pouch failure should be addressed with the appropriate workup and treatment plans formulated according with the patient's wishes. This article will discuss the identification, workup, and treatment options for pouch failure after IPAA.

Contiguous gene deletion of chromosome 2p16.3-p21 as a cause of Lynch syndrome.

Lynch syndrome is an autosomal dominant condition caused by pathogenic mutations in the DNA mismatch repair (MMR) genes. Although commonly associated with clinical features such as intellectual disability and congenital anomalies, contiguous gene deletions may also result in cancer predisposition syndromes. We report on a 52-year-old male with Lynch syndrome caused by deletion of chromosome 2p16.3-p21. The patient had intellectual disability and presented with a prostatic adenocarcinoma with an incidentally identified synchronous sigmoid adenocarcinoma that exhibited deficient MMR with an absence of MSH2 and MSH6 protein expression. Family history was unrevealing. Physical exam revealed short stature, brachycephaly with a narrow forehead and short philtrum, brachydactyly of the hands, palmar transverse crease, broad and small feet with hyperpigmentation of the soles. The patient underwent total colectomy with ileorectal anastomosis for a pT3N1 sigmoid adenocarcinoma. Germline genetic testing of the MSH2, MSH6, and EPCAM genes revealed full gene deletions. SNP-array based DNA copy number analysis identified a deletion of 4.8 Mb at 2p16.3-p21. In addition to the three Lynch syndrome associated genes, the deleted chromosomal section encompassed genes including NRXN1, CRIPT, CALM2, FBXO11, LHCGR, MCFD2, TTC7A, EPAS1, PRKCE, and 15 others. Contiguous gene deletions have been described in other inherited cancer predisposition syndromes, such as Familial Adenomatous Polyposis. Our report and review of the literature suggests that contiguous gene deletion within the 2p16-p21 chromosomal region is a rare cause of Lynch syndrome, but presents with distinct phenotypic features, highlighting the need for recognition and awareness of this syndromic entity.

Organ-Preserving Strategies for the Management of Near-Complete Responses in Rectal Cancer after Neoadjuvant Chemoradiation.

In recent years, organ preservation has been considered a feasible alternative to total mesorectal excision for patients with locally advanced rectal cancer with a clinical complete response to neoadjuvant therapy. However, the degree of tumor response to neoadjuvant therapy is variable. A fraction of the patients who did not achieve a complete response had grossly visible tumors. These patients, with clearly incomplete clinical response, need a total mesorectal excision. In addition, some patients with a significant tumor response still have some abnormalities in the bowel wall, such as superficial ulceration or tissue nodularity, which, while not conclusive for the presence of a tumor, are indicative of the possibility of a residual tumor in the bowel wall or in mesorectal lymph nodes. The management of patients with a so-called near-complete clinical response to neoadjuvant therapy is controversial. In this article, we will review the clinical and radiological criteria that define a clinical response to neoadjuvant therapy, possible treatment strategies, and follow-up protocols. We will also discuss patient and tumor characteristics that in our opinion can be useful in selecting the most appropriate treatment alternative. Although organ preservation and quality of life are important, the primary goal of treatment for these patients should be local tumor control and long-term survival.

Anorectal Function and Quality of Life in Patients With Early Stage Rectal Cancer Treated With Chemoradiation and Local Excision.

BACKGROUND: Little is known about anorectal function and quality of life after chemoradiation followed by local excision, which is an alternative to total mesorectal excision for selected patients with early rectal cancer. OBJECTIVE: The purpose of this study was to prospectively assess anorectal function and health-related quality of life of patients with T2N0 rectal cancer who were treated with an alternative approach. DESIGN: This was a prospective, phase II trial. SETTINGS: The study was multicentric (American College of Surgeons Oncology Group trial Z6041). INTERVENTIONS: Patients with stage cT2N0 rectal adenocarcinomas were treated with an oxaliplatin/capecitabine-based chemoradiation regimen followed by local excision. MAIN OUTCOME MEASURES: Anorectal function and quality of life were assessed at enrollment and 1 year postoperatively with the Fecal Incontinence Severity Index, Fecal Incontinence Quality of Life scale, and Functional Assessment of Cancer Therapy-Colorectal Questionnaire. Results were compared, and multivariable analysis was performed to identify predictors of outcome. RESULTS: Seventy-one patients (98%) were evaluated at enrollment and 66 (92%) at 1 year. Compared with baseline, no significant differences were found on Fecal Incontinence Severity Index scores at 1 year. Fecal Incontinence Quality of Life results were significantly worse in the lifestyle (p < 0.001), coping/behavior (p < 0.001), and embarrassment (p = 0.002) domains. There were no differences in the Functional Assessment of Cancer Therapy overall score, but the physical well-being subscale was significantly worse and emotional well-being was improved after surgery. Treatment with the original chemoradiation regimen predicted worse depression/self-perception and embarrassment scores in the Fecal Incontinence Quality of Life, and male sex was predictive of worse scores in the Functional Assessment of Cancer Therapy overall score and trial outcome index. LIMITATIONS: Small sample size, relatively short follow-up, and absence of information before cancer diagnosis were study limitations. CONCLUSIONS: Chemoradiation followed by local excision had minimal impact on anorectal function 1 year after surgery. Overall quality of life remained stable, with mixed effects on different subscales. This information should be used to counsel patients about expected outcomes.

Impact of Organ-Preserving Strategies on Anorectal Function in Patients with Distal Rectal Cancer Following Neoadjuvant Chemoradiation.

BACKGROUND: Organ-preserving strategies have been considered for patients with distal rectal cancer and complete or near-complete response to neoadjuvant chemoradiation to avoid the functional consequences of radical surgery. Transanal endoscopic microsurgery and no immediate surgery (watch and wait) have been considered in selected patients. OBJECTIVE: The aim of this study is to compare anorectal function following these 2 organ-preserving strategies (transanal endoscopic microsurgery and watch and wait) for rectal cancer with complete or near-complete response to neoadjuvant chemoradiation. DESIGN: This study is based on the comparison of prospectively collected data. SETTINGS: This study was conducted at a single center. PATIENTS: Consecutive patients with distal rectal cancer undergoing neoadjuvant chemoradiation (50.4-54 Gy and 5-fluorouracil-based chemotherapy) were prospectively studied. Patients with complete clinical response were managed by watch and wait. Patients with near-complete response (≤3 cm, ycT1-2N0) were managed by transanal endoscopic microsurgery. MAIN OUTCOME MEASURES: Functional outcomes were determined by anorectal manometry and Fecal Incontinence Index and Quality of Life assessment. RESULTS: Two groups of patients were included in the study. Twenty-nine patients with near-complete response undergoing transanal endoscopic microsurgery and 53 with complete response after watch and wait were assessed. Baseline features were similar between groups. Patients undergoing transanal endoscopic microsurgery had worse resting/squeeze pressures (p = 0.004) and rectal capacity (p = 0.002). In addition, their incontinence scores (2.3 vs. 6.5; p < 0.001) and quality-of-life questionnaire responses (in all domains; p ≤ 0.01) were significantly worse in comparison with patients undergoing watch and wait. LIMITATIONS: This study was limited by the small sample size and the absence of baseline anorectal function information. CONCLUSIONS: Nonoperative management of patients with complete clinical response following chemoradiation results in better anorectal function in comparison with patients with near-complete response managed by transanal endoscopic microsurgery. In the absence of clinically detectable residual cancer, this latter approach may result in significant worsening of anorectal function.

Organ preservation for clinical T2N0 distal rectal cancer using neoadjuvant chemoradiotherapy and local excision (ACOSOG Z6041): results of an open-label, single-arm, multi-institutional, phase 2 trial.

BACKGROUND: Local excision is an organ-preserving treatment alternative to transabdominal resection for patients with stage I rectal cancer. However, local excision alone is associated with a high risk of local recurrence and inferior survival compared with transabdominal rectal resection. We investigated the oncological and functional outcomes of neoadjuvant chemoradiotherapy and local excision for patients with stage T2N0 rectal cancer. METHODS: We did a multi-institutional, single-arm, open-label, non-randomised, phase 2 trial of patients with clinically staged T2N0 distal rectal cancer treated with neoadjuvant chemoradiotherapy at 26 American College of Surgeons Oncology Group institutions. Patients with clinical T2N0 rectal adenocarcinoma staged by endorectal ultrasound or endorectal coil MRI, measuring less than 4 cm in greatest diameter, involving less than 40% of the circumference of the rectum, located within 8 cm of the anal verge, and with an Eastern Cooperative Oncology Group performance status of at least 2 were included in the study. Neoadjuvant chemoradiotherapy consisted of capecitabine (original dose 825 mg/m(2) twice daily on days 1-14 and 22-35), oxaliplatin (50 mg/m(2) on weeks 1, 2, 4, and 5), and radiation (5 days a week at 1·8 Gy per day for 5 weeks to a dose of 45 Gy, followed by a boost of 9 Gy, for a total dose of 54 Gy) followed by local excision. Because of adverse events during chemoradiotherapy, the dose of capecitabine was reduced to 725 mg/m(2) twice-daily, 5 days per week, for 5 weeks, and the boost of radiation was reduced to 5·4 Gy, for a total dose of 50·4 Gy. The primary endpoint was 3-year disease-free survival for all eligible patients (intention-to-treat population) and for patients who completed chemotherapy and radiation, and had ypT0, ypT1, or ypT2 tumours, and negative resection margins (per-protocol group). This study is registered with ClinicalTrials.gov, number NCT00114231. FINDINGS: Between May 25, 2006, and Oct 22, 2009, 79 eligible patients were recruited to the trial and started neoadjuvant chemoradiotherapy. Two patients had no surgery and one had a total mesorectal excision. Four additional patients completed protocol treatment, but one had a positive margin and three had ypT3 tumours. Thus, the per-protocol population consisted of 72 patients. Median follow-up was 56 months (IQR 46-63) for all patients. The estimated 3-year disease-free survival for the intention-to-treat group was 88·2% (95% CI 81·3-95·8), and for the per-protocol group was 86·9% (79·3-95·3). Of 79 eligible patients, 23 (29%) had grade 3 gastrointestinal adverse events, 12 (15%) had grade 3-4 pain, and 12 (15%) had grade 3-4 haematological adverse events during chemoradiation. Of the 77 patients who had surgery, six (8%) had grade 3 pain, three (4%) had grade 3-4 haemorrhage, and three (4%) had gastrointestinal adverse events. INTERPRETATION: Although the observed 3-year disease free survival was not as high as anticipated, our data suggest that neoadjuvant chemoradiotherapy followed by local excision might be considered as an organ-preserving alternative in carefully selected patients with clinically staged T2N0 tumours who refuse, or are not candidates for, transabdominal resection. FUNDING: National Cancer Institute and Sanofi-Aventis.

Total mesorectal excision and sphincter preservation: the early steps of rectal cancer surgery / Excisão total do mesorreto e esfíncter: os primeiros passos de uma cirurgia de câncer retal

The treatment of rectal cancer has evolved significantly over the last 100 years. Standardization of total mesorectal excision and the development of techniques for sphincter preservation have resulted in significant improvements in the management of this disease. Still, local disease control and functional outcomes of sphincter preserving procedures remain a relevant issue. In this historical paper, the oncological and functional outcomes of patients with rectal cancer treated between 1960 and 1971 by a pioneer woman surgeon using a sphincter preserving approach and a technique resembling total mesorectal excision performed at that time are reported. The results reflect one of the earliest steps of partial intersphincteric resection and total mesorectal excision with good oncological outcomes (2% local recurrence) and acceptable functional outcomes in a highly selected group of patients. (AU)

O tratamento do câncer de reto tem evoluído significativamente ao longo dos últimos 100 anos. A padronização da excisão total do mesorreto e o desenvolvimento de técnicas com preservação do esfíncter resultaram em melhorias significativas no tratamento da doença. Ainda assim, o controle local da doença e os resultados funcionais dos procedimentos de preservação do esfíncter continuam a ser uma questão relevante. Nesse documento histórico, são relatados os resultados oncológicos e funcionais de pacientes com câncer retal, tratados entre 1960 e 1971, utilizando-se uma abordagem com preservação do esfíncter e uma técnica parecida com a excisão total do mesorreto realizada por uma cirurgiã pioneira naquela época. Os resultados refletem um dos primeiros passos de ressecção parcial interesfinctérica e a excisão total do mesorreto com bons resultados oncológicos (2% de recidiva local), e os resultados funcionais aceitáveis em um grupo altamente selecionado de pacientes. (AU)

Local recurrence after complete clinical response and watch and wait in rectal cancer after neoadjuvant chemoradiation: impact of salvage therapy on local disease control.

PURPOSE: To review the risk of local recurrence and impact of salvage therapy after Watch and Wait for rectal cancer with complete clinical response (cCR) after chemoradiation therapy (CRT). METHODS AND MATERIALS: Patients with cT2-4N0-2M0 distal rectal cancer treated with CRT (50.4-54 Gy + 5-fluorouracil-based chemotherapy) and cCR at 8 weeks were included. Patients with cCR were enrolled in a strict follow-up program with no immediate surgery (Watch and Wait). Local recurrence-free survival was compared while taking into account Watch and Wait strategy alone and Watch and Wait plus salvage. RESULTS: 90 of 183 patients experienced cCR at initial assessment after CRT (49%). When early tumor regrowths (up to and including the initial 12 months of follow-up) and late recurrences were considered together, 28 patients (31%) experienced local recurrence (median follow-up time, 60 months). Of those, 26 patients underwent salvage therapy, and 2 patients were not amenable to salvage. In 4 patients, local re-recurrence developed after Watch and Wait plus salvage. The overall salvage rate for local recurrence was 93%. Local recurrence-free survival at 5 years was 69% (all local recurrences) and 94% (after salvage procedures). Thirteen patients (14%) experienced systemic recurrence. The 5-year cancer-specific overall survival and disease-free survival for all patients (including all recurrences) were 91% and 68%, respectively. CONCLUSIONS: Local recurrence may develop in 31% of patients with initial cCR when early regrowths (≤ 12 months) and late recurrences are grouped together. More than half of these recurrences develop within 12 months of follow-up. Salvage therapy is possible in ≥ 90% of recurrences, leading to 94% local disease control, with 78% organ preservation.

Cylindrical abdominoperineal resection rationale, technique and controversies / Amputação abdominoperineal cilíndrica racional, técnica e controvérsias

Surgery remains the cornerstone in rectal cancer treatment. Abdominoperineal excision (APE), described more than 100 years ago, remains as an important procedure for the treatment of selected advanced distal tumors with direct invasion of the anal sphincter or preoperative fecal incontinence. Historically, oncological outcomes of patients undergoing APE have been worse when compared to sphincter preserving operations. More recently, it has been suggested that patients undergoing APE for distal rectal cancer are more likely to have positive circumferential resection margins and intraoperative perforation, known surrogate markers for local recurrence. Recently, an alternative approach known as "Extralevator Abdominoperineal Excision" has been described in an effort to improve rates of circumferential margin positivity possibly resulting in better oncological outcomes compared to the standard procedure. The objective of this paper is to provide a technical description and compare available data of both Extralevator and Standard abdominal perineal excision techniques. (AU)

Um dos pilares mais importantes no tratamento do câncer de reto ainda é a ressecção cirúrgica. A amputação de reto, ou excisão abdomino-perineal do reto (APE), descrita há mais de 100 anos, continua sendo um procedimento importante para o tratamento de tumores retais distais que invadem o aparelho esfincteriano ou em casos de incontinência pré-operatória. Entretanto, os resultados oncológicos dos pacientes submetidos à APE são piores quando comparados com os pacientes submetidos a procedimentos com preservação esfincteriana. Recentemente, foi sugerido que os pacientes submetidos à APE por câncer de reto distal apresentam mais frequentemente margem radial positiva, assim como perfuração intraoperatória do tumor, fatos reconhecidamente associados à recidiva local. Uma nova técnica cirúrgica conhecida como "Amputação de reto extraelevador ou cilíndrica" tem sido descrita em um esforço para reduzir as taxas de margem radial positivas, sugerindo melhores resultados oncológicos quando comparada com o procedimento convencional. O objetivo deste trabalho é descrever a técnica deste procedimento e comparar seus resultados com os obtidos com a técnica convencional de acordo com a evidência disponível. (AU)

Amputación abdominoperineal cilíndrica: racionalidad y aspectos técnicos / Cylindric Abdominoperineal Resection: rational and technique

La resección quirúrgica sigue siendo la piedra angular de la terapia curativa en el cáncer de recto. La amputación abdominoperineal implica la remoción en bloque del recto, mesorrecto, aparato esfinteriano y el ano; con la creación de una colostomía definitiva. Esta cirugía es la propuesta para pacientes sin posibilidad de conservación esfinteriana. Este grupo representa aproximadamente el 80% de los pacientes con lesiones a menos de 5 cm del margen anal y aquellos con una continencia preoperatoria deficiente. Recientemente una modificación de la técnica denominada ôAmputación abdominoperineal extraelevadorö destinada a la ampliación del margen circunferencial sugiere mejores resultados oncológicos que la técnica clásica. El siguiente trabajo tiene por objetivo caracterizar y describir a la amputación abdominoperineal cilíndrica en comparación a la técnica clásica. (AU)

Surgery remains the cornerstone in rectal cancer treatment. Abdominoperineal resection involves the en bloc removal of the rectum, mesorectum, sphincters and anus with confection of a definitive colostomy. This surgery is indicated in patients without the possibility of sphincter preservation. This group represents approximately 80% of patients with lesions <5 cm from the anal verge and those with preoperative incontinence. Recently ôExtralevator Abdominoperineal Excisionö has been described to improve rates of circumferential margin positivity suggesting better oncological outcomes compared to the standard procedure. The objective of this paper is to provide a technical description and compare available data of both Extralevator and Standard techniques. (AU)

Amputación abdominoperineal cilíndrica: racionalidad y aspectos técnicos / Cylindric Abdominoperineal Resection: rational and technique

La resección quirúrgica sigue siendo la piedra angular de la terapia curativa en el cáncer de recto. La amputación abdominoperineal implica la remoción en bloque del recto, mesorrecto, aparato esfinteriano y el ano; con la creación de una colostomía definitiva. Esta cirugía es la propuesta para pacientes sin posibilidad de conservación esfinteriana. Este grupo representa aproximadamente el 80% de los pacientes con lesiones a menos de 5 cm del margen anal y aquellos con una continencia preoperatoria deficiente. Recientemente una modificación de la técnica denominada “Amputación abdominoperineal extraelevador” destinada a la ampliación del margen circunferencial sugiere mejores resultados oncológicos que la técnica clásica. El siguiente trabajo tiene por objetivo caracterizar y describir a la amputación abdominoperineal cilíndrica en comparación a la técnica clásica.

Surgery remains the cornerstone in rectal cancer treatment. Abdominoperineal resection involves the en bloc removal of the rectum, mesorectum, sphincters and anus with confection of a definitive colostomy. This surgery is indicated in patients without the possibility of sphincter preservation. This group represents approximately 80% of patients with lesions <5 cm from the anal verge and those with preoperative incontinence. Recently “Extralevator Abdominoperineal Excision” has been described to improve rates of circumferential margin positivity suggesting better oncological outcomes compared to the standard procedure. The objective of this paper is to provide a technical description and compare available data of both Extralevator and Standard techniques.

Optimal timing for assessment of tumor response to neoadjuvant chemoradiation in patients with rectal cancer: do all patients benefit from waiting longer than 6 weeks?

PURPOSE: To estimate the metabolic activity of rectal cancers at 6 and 12 weeks after completion of chemoradiation therapy (CRT) by 2-[fluorine-18] fluoro-2-deoxy-d-glucose-labeled positron emission tomography/computed tomography ([(18)FDG]PET/CT) imaging and correlate with response to CRT. METHODS AND MATERIALS: Patients with cT2-4N0-2M0 distal rectal adenocarcinoma treated with long-course neoadjuvant CRT (54 Gy, 5-fluouracil-based) were prospectively studied (ClinicalTrials.org identifier NCT00254683). All patients underwent 3 PET/CT studies (at baseline and 6 and 12 weeks from CRT completion). Clinical assessment was at 12 weeks. Maximal standard uptake value (SUVmax) of the primary tumor was measured and recorded at each PET/CT study after 1 h (early) and 3 h (late) from (18)FDG injection. Patients with an increase in early SUVmax between 6 and 12 weeks were considered "bad" responders and the others as "good" responders. RESULTS: Ninety-one patients were included; 46 patients (51%) were "bad" responders, whereas 45 (49%) patients were "good" responders. "Bad" responders were less likely to develop complete clinical response (6.5% vs. 37.8%, respectively; P=.001), less likely to develop significant histological tumor regression (complete or near-complete pathological response; 16% vs. 45%, respectively; P=.008) and exhibited greater final tumor dimension (4.3 cm vs. 3.3 cm; P=.03). Decrease between early (1 h) and late (3 h) SUVmax at 6-week PET/CT was a significant predictor of "good" response (accuracy of 67%). CONCLUSIONS: Patients who developed an increase in SUVmax after 6 weeks were less likely to develop significant tumor downstaging. Early-late SUVmax variation at 6-week PET/CT may help identify these patients and allow tailored selection of CRT-surgery intervals for individual patients.

Consideraciones sobre respuesta clínica completa en el cáncer de recto luego de quimioradioterapia neoadyuvante / Considerations about complete clinical response in rectal cancer after neoadyuvant chemotherapy

Luego de la quimioradioterapia neoadyuvante un porcentaje de adenocarcinomas de recto bajo localmente avanzados presentarán remisión total de la lesión, a esto se lo conoce como Respuesta Clínica Completa; en estos casos la cirugía puede ser innecesaria. Nuestro grupo desde principios de los noventa ha incluído estos pacientes en un protocolo estricto de seguimiento que ha demostrado ser igual de seguro que el tratamiento convencional, sin las morbilidades de la cirugía radical. El presente reporte tiene por objeto definir lo que consideramos una Respuesta Clínica Completa, analizar sus implicancias y presentar nuestra experiencia en el manejo de este acontecimmiento.

After neoadjuvant chemoradiation, some patients with locally advanced low rectal adenocarcinoma will present with total tumor regression, this situation is known as Complete Clinical Response (CCR). In this setting immediate radical surgery could be unnecessary. Since the early nineties, our group has included this patients in a striet follow-up protocol, wich has proven to be oncologically equally safe as conventional treatment, without the morbidities of radical surgery. The objective of this report is to define what we consider a CCR and to present our experience in the management of this clinical situation.