Can Endorectal Ultrasound, MRI, and Mucosa Integrity Accurately Predict the Complete Response for Mid-Low Rectal Cancer After Preoperative Chemoradiation? A Prospective Observational Study from a Single Medical Center.

BACKGROUND: Patients with locally advanced rectal cancer could be managed by a watch-and-wait approach if they achieve clinical complete response after preoperative chemoradiotherapy. Mucosal integrity, endorectal ultrasound, and rectal MRI are used to evaluate clinical complete response; however, the accuracy remains questionable. Clinical practice based on those assessment methods needs more data and discussion. OBJECTIVE: The aim of this prospective study was to evaluate the accuracy of mucosal integrity, endorectal ultrasound, and rectal MRI to predict clinical complete response after chemoradiotherapy. DESIGN: Endorectal ultrasound and rectal MRI were undertaken 6 to 7 weeks after preoperative chemoradiation therapy. Patients then received radical surgery based on the principles of total mesorectal excision. Preoperative tumor staging achieved by endorectal ultrasound and rectal MRI was compared with postoperative staging by pathologic examination. Sensitivity, specificity, and accuracy of each evaluation method were calculated. SETTINGS: The study was conducted at a single tertiary care center. PATIENTS: Patients diagnosed with mid-low rectal cancer by biopsy between May 2014 and December 2016 were enrolled in this study. RESULTS: A total of 124 patients were enrolled in this study, and postoperative pathology revealed that 20 patients (16.13%) achieved complete response (ypT0N0). The sensitivity of mucosal integrity, endorectal ultrasound, and MRI to predict clinical complete response was 25%. The specificity of mucosal integrity, endorectal ultrasound, and MRI was 94.23%, 93.90%, and 93.27%. The combination of each 2 or all 3 methods did not improve accuracy. Regression analysis showed that none of these methods could predict postoperative ypT0. LIMITATIONS: The sample size is small, and we did not focus on the follow-up data and cannot compare prognosis data with previous research studies. CONCLUSIONS: Both single-method and combined mucosal integrity, endorectal ultrasound, and rectal MRI have poor correlation with postoperative pathologic examination. A watch-and-wait approach based on these methods might not be a proper strategy compared with radical surgery after neoadjuvant therapy. See Video Abstract at http://links.lww.com/DCR/A693.

Resection of multiple rectal carcinoids with transanal endoscopic microsurgery: case report.

Multiple rectal carcinoids are rare. Due to the unreliability of endoscopic polypectomy in treating these submucosal lesions, a laparotomy is usually performed. We present a case report on multiple rectal carcinoids with three carcinoid foci<10 mm in diameter located in the mid-rectum. Preoperative examination showed the lesions to be confined to the submucosal layer with no perirectal nodal involvement. A transanal endoscopic microsurgery was successfully performed to remove the three lesions with accurate full-thickness resection followed by secured suture closure. The postoperative pathology revealed neuroendocrine tumors G1 (carcinoids) located within the submucosal layer without lymphatic or vessel infiltration. Both the deep and lateral surgical margins were completely free of tumor cells. The patient recovered quickly and uneventfully. No tumor recurrence was observed at the six-month follow-up. For the multiple small rectal carcinoids without muscularis propria or lymphatic invasion, transanal endoscopic microsurgery offers a reliable and efficient alternative approach to traditional laparotomy for select patients, with the added advantages of minimally invasive surgery.

[Impact of neoadjuvant therapy on lymph nodes retrieval in locally advanced mid-low rectal carcinoma].

OBJECTIVE: To study the impact of neoadjuvant therapy on lymph nodes retrieval in locally advanced mid-low rectal carcinoma. METHODS: Data collected from 120 patients with locally advanced mid-low rectal cancer (T2-4 and/or N1-2M0) treated from January 2005 to June 2008 was investigated. The patients were divided into two groups: the study group (n=54) was treated with neoadjuvant therapy (preoperative radiation with a total dosage of 50 Gy and synchronous 5-Fu-based chemotherapy) followed by radical tumor resection 4-6 weeks after;the control group (n=66) underwent primary surgery without neoadjuvant therapy. The clinical stage was evaluated before and after neoadjuvant therapy. The total lymph nodes yields, as well as the tumor-positive lymph nodes of each resected specimen was compared between the two groups statistically. RESULTS: Clinical downstage was achieved in 30 cases (56%) in study group after neoadjuvant therapy. The number of total lymph nodes and positive lymph nodes harvested from each resected specimen in the control group were 14+/-7 and 2.2+/-3.7, meanwhile those were 9+/-6 and 0.7+/-2.4 in study group, which were all significantly lower than those in control group (P<0.01). CONCLUSIONS: Preoperative radiotherapy combined with chemotherapy can downstage the tumor and reduce the retrieval rate of total lymph nodes and positive lymph nodes in locally advanced rectal cancer. It is necessary to retrieve as many lymph nodes as possible for it has some prognostic significance for the patients.

Color Doppler ultrasonography appearances of renal vein thrombosis and its diagnostic value.

OBJECTIVE: To evaluate color Doppler ultrasonography (CDU) appearances of renal vein thrombosis (RVT) and its diagnostic value. METHODS: Ten patients with RVT were analyzed retrospectively. Renal structure, distributions of intrarenal flow signals, echogenicity, and flow fullness in main renal veins were observed with CDU. Resistance index (RI) was recorded from the waveforms of segmental or interlobar renal artery. RESULTS: Ten kidneys in nine patients were confirmed to have thrombus within the main renal veins, and one patient was confirmed to have thrombus within the small intrarenal veins. The appearances of the main renal vein thrombosis included full of solid echogenicity or strip echogenicity and complete or partial filling defect within the main renal veins, and absent or a few intrarenal venous flow signals in 70% of kidneys involved. The appearances of intrarenal vein thrombosis included obscure renal structure and no venous flow signal within the involved part of the kidneys. Reverse diastolic flow in the intrarenal artery had only a sensitivity of 36% (4/11); in other 7 kidneys without intrarenal arterial reverse diastolic flow, increased RI (mean, 0.84; range, 0.74-0.96) was found. CONCLUSION: CDU is helpful for rapid clinical diagnosis and follow-up of RVT, and therefore can be the first imaging modality of choice for RVT.