Are pretreatment simulation estimates predictive of actual rectal and bladder doses delivered during radiation for prostate cancer

Long-Term Outcome of Rectal Cancer With Clinically (EUS/MRI) Metastatic Mesorectal Lymph Nodes Treated by Neoadjuvant Chemoradiation: Role of Organ Preservation Strategies in Relation to Pathologic Response

BACKGROUND

Organ preservation strategies are under investigation for patients with locally advanced rectal cancer (LARC) who achieve a complete pathologic response in the primary tumor (ypT0) after neoadjuvant chemoradiation therapy (CRT). This study explored the value of this approach for cN+ patients.

METHODS

Data were retrieved from our institutional prospective rectal cancer database. Tumors with mesorectal lymph nodes larger than 5 mm shown on endorectal ultrasonography, pelvic magnetic resonance imaging, or both were staged as cN+.

RESULTS

The study population comprised 226 patients (142 men and 84 women; median age, 64 years) with LARC who underwent CRT followed by surgery including total mesorectal excision (TME) (n = 179) and full-thickness local excision (LE) (n = 47) between 1996 and 2013. At staging, 123 patients (54.4 %) were cN+. In 65 cases (28.7 %), ypCR was observed. Metastatic mesorectal lymph nodes (ypN+) were detected in 41.6 % of the cN+ patients and in 2.8 % of the cN0 patients (P < 0.01). Among the cN+ patients, 16 % of the ypT0 cases were ypN+ compared with 51.8 % of the no-ypT0 cases (P < 0.01). Among the cN+ patients who underwent TME, the 5-year disease-specific survival (DSS) and disease-free survival (DFS) rates were respectively 100 and 91.6 % for the ypT0 patients compared with 71.2 and 58.0 % for the no-ypT0 patients (P = 0.01). Among the ypN+ patients, the 5-year DSS and DFS rates were both 100 % for the ypT0 cases compared with 59.1 and 43.3 % for the no-ypT0 patients. Among the cN+ and ypT0 patients, the 5-year DSS and DFS were respectively 100 and 85.7 % for the TME patients compared with 100 and 91.6 % for the LE patients. In the multivariate analysis, ypT0 was the only independent prognostic factor.

CONCLUSIONS

Protocols aimed at organ preservation in LARC that achieve ypT0 after CRT can be offered also to cN+ patients.

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.

A phase II trial of neoadjuvant chemoradiation and local excision for T2N0 rectal cancer: preliminary results of the ACOSOG Z6041 trial

PURPOSE

We designed American College of Surgeons Oncology Group (ACOSOG) Z6041, a prospective, multicenter, single-arm, phase II trial to assess the efficacy and safety of neoadjuvant chemoradiation (CRT) and local excision (LE) for T2N0 rectal cancer. Here, we report tumor response, CRT-related toxicity, and perioperative complications (PCs).

METHODS

Clinically staged T2N0 rectal cancer patients were treated with capecitabine and oxaliplatin during radiation followed by LE. Because of toxicity, capecitabine and radiation doses were reduced. LE was performed 6 weeks after CRT. Patients were evaluated for clinical and pathologic response. CRT-related complications and PCs were recorded.

RESULTS

Ninety patients were accrued; 6 received nonprotocol treatment. The remaining 84 were 65% male; median age 63 years; 83% Eastern Cooperative Oncology Group performance score 0; 92% white; mean tumor size 2.9 cm; and average distance from anal verge 5.1 cm. Five patients were considered ineligible. Therapy was completed per protocol in 79 patients, but two patients did not undergo LE. Among 77 eligible patients who underwent LE, 34 patients achieved a pathologic complete response (44%) and 49 (64%) tumors were downstaged (ypT0-1), but 4 patients (5%) had ypT3 tumors. Five LE specimens contained lymph nodes; one T3 tumor had a positive node. All but one patient had negative margins. Thirty-three (39%) of 84 patients developed CRT-related grade ≥3 complications. Rectal pain was the most common PC.

CONCLUSIONS

CRT before LE for T2N0 tumors results in a high pathologic complete response rate and negative resection margins. However, complications during CRT and after LE are high. The true efficacy of this approach will ultimately be assessed by the long-term oncologic outcomes.

Local excision and transanal endoscopic microsurgery in the management of rectal cancer with a focus on early carcinoma

Transanal endoscopic microsurgery (TEMS) will play an even greater role in the treatment of rectal cancer as the UK national colorectal cancer screening program becomes national. With more rectal tumors being uncovered at earlier stages, a greater emphasis will be placed on treatment options that do not involve radical surgery and the possibility of a stoma. This article reviews the data surrounding TEMS, focusing on its current role in the treatment of early rectal cancer but with a view on how this option may develop in the future, particularly with regards to the more advanced rectal cancers and in view of the improved chemoradiotherapy regimens available. The data is reviewed and some of the more controversial issues discussed.