Combined use of magnetic seed and tracer in breast conserving surgery with sentinel lymph node biopsy for non-palpable breast lesions: A pilot study describing pitfalls and solutions.

Backgrounds: Traditionally, breast conserving surgery for non-palpable breast cancer is guided by wire or radioactive seed and radioactive tracer for sentinel lymph node biopsy (SLNB). Alternatively, a stain-less magnetic seed and superparamagnetic iron oxide tracer (SPIO) can be combined as a radioactive-free technique. The aim of this study was to define the pitfalls we encountered during implementation of this combined technique and provide solutions resulting in an instruction manual for a radio-active free procedure.

Sentinel lymph node mapping with superparamagnetic iron oxide for melanoma: a pilot study in healthy participants to establish an optimal MRI workflow protocol.

Background: Current pre-operative Sentinel Lymph Node (SLN) mapping using dual tracing is associated with drawbacks (radiation exposure, logistic challenges). Superparamagnetic iron oxide (SPIO) is a non-inferior alternative for SLN mapping in breast cancer patients. Limited research has been performed on SPIO use and pre-operative MRI in melanoma patients to identify SLNs.

Impact of the COVID-19 pandemic on incidence and severity of acute appendicitis: a comparison between 2019 and 2020.

Background: During the COVID-19 pandemic, a decrease in the number of patients presenting with acute appendicitis was observed. It is unclear whether this caused a shift towards more complicated cases of acute appendicitis. We compared a cohort of patients diagnosed with acute appendicitis during the 2020 COVID-19 pandemic with a 2019 control cohort.

Organ Preservation in Rectal Cancer After Chemoradiation: Should We Extend the Observation Period in Patients with a Clinical Near-Complete Response?

Background: To assess whether extending the observation period in patients with a near clinical complete response (near cCR) after chemoradiation (CRT) leads to an impaired oncological outcome.

Methods: Patients who had a clinical complete response (cCR) 8-10 weeks after CRT restaging with magnetic resonance imaging and endoscopy were offered a watch-and-wait strategy (W&W1), while patients with a near cCR were offered to undergo local excision or a second restaging 6-12 weeks later. Patients who achieved a cCR at the second restaging were also offered a watch-and-wait strategy (W&W2).

Quality of Life in Rectal Cancer Patients After Chemoradiation: Watch-and-Wait Policy Versus Standard Resection - A Matched-Controlled Study.

Background: Fifteen to twenty percent of patients with locally advanced rectal cancer have a clinical complete response after chemoradiation therapy. These patients can be offered nonoperative organ-preserving treatment, the so-called watch-and-wait policy. The main goal of this watch-and-wait policy is an anticipated improved quality of life and functional outcome in comparison with a total mesorectal excision, while maintaining a good oncological outcome.

MRI surveillance for the detection of local recurrence in rectal cancer after transanal endoscopic microsurgery.

Objectives: To evaluate diagnostic performance of follow-up MRI for detection of local recurrence of rectal cancer after transanal endoscopic microsurgery (TEM).

Methods: Between January 2006 and February 2014, 81 patients who underwent TEM were included. Two expert readers (R1 and R2), independently evaluated T2-weighted (T2W) MRI and diffusion-weighted (DWI) MRI for the detection of local recurrence, retrospectively, and recorded confidence on a five-point scale.

Correlation between quantitative and semiquantitative parameters in DCE-MRI with a blood pool agent in rectal cancer: can semiquantitative parameters be used as a surrogate for quantitative parameters?

Purpose: The aim of this study was to assess correlation between quantitative and semiquantitative parameters in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in rectal cancer patients, both in a primary staging and restaging setting.

Materials And Methods: Nineteen patients were included with DCE-MRI before and/or after neoadjuvant therapy. DCE-MRI was performed with gadofosveset trisodium (Ablavar, Lantheus Medical Imaging, North Billerica, Massachusetts, USA).

Long-term Outcome of an Organ Preservation Program After Neoadjuvant Treatment for Rectal Cancer.

Background: The aim of this study was to establish the oncological and functional results of organ preservation with a watch-and-wait approach (W&W) and selective transanal endoscopic microsurgery (TEM) in patients with a clinical complete or near-complete response (cCR) after neoadjuvant chemoradiation for rectal cancer.

Methods: Between 2004 and 2014, organ preservation was offered if response assessment with digital rectal examination, endoscopy, and MRI showed (near) cCR. Watch-and-wait was offered for cCR, and two options were offered for near cCR: TEM or reassessment after three months.

CT texture analysis in colorectal liver metastases: A better way than size and volume measurements to assess response to chemotherapy?

Background: Response Evaluation Criteria In Solid Tumors (RECIST) are known to have limitations in assessing the response of colorectal liver metastases (CRLMs) to chemotherapy.

Objective: The objective of this article is to compare CT texture analysis to RECIST-based size measurements and tumor volumetry for response assessment of CRLMs to chemotherapy.

Methods: Twenty-one patients with CRLMs underwent CT pre- and post-chemotherapy.

Good and complete responding locally advanced rectal tumors after chemoradiotherapy: where are the residual positive nodes located on restaging MRI?

Purpose: Aim of this study was to evaluate the distribution of persistent mesorectal lymph node metastases on restaging MRI in patients with a good or complete response of their primary tumor (ypT0-2) after CRT for locally advanced rectal cancer.

Methods: Two hundred and twenty eight locally advanced rectal cancer patients underwent CRT, which resulted in a good response (downstaging to yT0-2) in 144 patients. Forty-nine patients were excluded (no surgery/insufficient follow-up or lacking lesion-by-lesion histology results).

Prospective, Multicenter Validation Study of Magnetic Resonance Volumetry for Response Assessment After Preoperative Chemoradiation in Rectal Cancer: Can the Results in the Literature be Reproduced?

Purpose: To review the available literature on tumor size/volume measurements on magnetic resonance imaging for response assessment after chemoradiotherapy, and validate these cut-offs in an independent multicenter patient cohort.

Methods And Materials: The study included 2 parts. (1) Review of the literature: articles were included that assessed the accuracy of tumor size/volume measurements on magnetic resonance imaging for tumor response assessment.

MRI and diffusion-weighted MRI to diagnose a local tumour regrowth during long-term follow-up of rectal cancer patients treated with organ preservation after chemoradiotherapy.

Objectives: To assess the value of MRI and diffusion-weighted imaging (DWI) for diagnosing local tumour regrowth during follow-up of organ preservation treatment after chemoradiotherapy for rectal cancer.

Methods: Seventy-two patients underwent organ preservation treatment (chemoradiotherapy + transanal endoscopic microsurgery or "wait-and-see") and were followed with MRI including DWI (1.5 T) every 3 -months during the first year and 6 months during following years.

Non-invasive MR assessment of macroscopic and microscopic vascular abnormalities in the rectal tumour-surrounding mesorectum.

Objectives: To evaluate the MRI macroscopic and microscopic parameters of mesorectal vasculature in rectal cancer patients.

Methods: Thirteen patients with rectal adenocarcinoma underwent a dynamic contrast-enhanced MRI at 1.5 T using a blood pool agent at the primary staging.

Magnetization transfer imaging to assess tumour response after chemoradiotherapy in rectal cancer.

Purpose: Single-slice magnetization transfer (MT) imaging has shown promising results for evaluating post-radiation fibrosis. The study aim was to evaluate the value of multislice MT imaging to assess tumour response after chemoradiotherapy by comparing magnetization transfer ratios (MTR) with histopathological tumour regression grade (TRG).

Materials And Methods: Thirty patients with locally advanced rectal cancer (cT3-4 and/or cN2) underwent routine restaging MRI 8 weeks post-chemoradiotherapy, including multislice MT-sequence, covering the entire tumour bed.

Whole-liver diffusion-weighted MRI histogram analysis: effect of the presence of colorectal hepatic metastases on the remaining liver parenchyma.

Objectives: To explore whether whole-liver diffusion-weighted MRI analysis (of the apparently normal liver parenchyma) can help differentiate between patients with colorectal liver metastasis and controls without liver disease.

Materials And Methods: Ten patients with colorectal liver metastasis and 10 controls with no focal/diffuse liver disease underwent liver MRI at 1.5 T including diffusion-weighted imaging (DWI; b-values 0, 50, 100, 500, 750, 1000).

Can perfusion MRI predict response to preoperative treatment in rectal cancer?

Background And Purpose: Dynamic contrast-enhanced MRI (DCE-MRI) provides information on perfusion and could identify good prognostic tumors. Aim of this study was to evaluate whether DCE-MRI using a novel blood pool contrast-agent can accurately predict the response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer.

Materials And Methods: Thirty patients underwent DCE-MRI before and 7-10weeks after chemoradiotherapy.

Whole-liver CT texture analysis in colorectal cancer: Does the presence of liver metastases affect the texture of the remaining liver?

Background: Liver metastases limit survival in colorectal cancer. Earlier detection of (occult) metastatic disease may benefit treatment and survival.

Objective: The objective of this article is to evaluate the potential of whole-liver CT texture analysis of apparently disease-free liver parenchyma for discriminating between colorectal cancer (CRC) patients with and without hepatic metastases.

MRI and Diffusion-weighted MRI Volumetry for Identification of Complete Tumor Responders After Preoperative Chemoradiotherapy in Patients With Rectal Cancer: A Bi-institutional Validation Study.

Background: Retrospective single-center studies have shown that diffusion-weighted magnetic resonance imaging (DWI) is promising for identification of patients with rectal cancer with a complete tumor response after neoadjuvant chemoradiotherapy (CRT), using certain volumetric thresholds.

Objective: This study aims to validate the diagnostic value of these volume thresholds in a larger, independent, and bi-institutional patient cohort.

Methods: A total of 112 patients with locally advanced rectal cancer (2 centers) treated with a long course of CRT were enrolled.

Value of gadofosveset-enhanced MRI and multiplanar reformatting for selecting good responders after chemoradiation for rectal cancer.

Objectives: Our primary objective was to evaluate diagnostic performance of gadofosveset T1-weighted magnetic resonance imaging (T1W MRI) for discriminating between ypT0-2 and ypT3-4 tumours after chemoradiation therapy (CRT) for rectal cancer compared with T2W MRI for a general and expert reader. Second objectives included assessing the value of multiplanar reformatting (MPR) and interobserver agreement.

Methods: A general and expert reader evaluated 49 patients for likelihood of ypT0-2 tumour after CRT on T2W, gadofosveset T1W MRI, and gadofosveset T1W MRI + T2W MRI.

Performance of gadofosveset-enhanced MRI for staging rectal cancer nodes: can the initial promising results be reproduced?

Objectives: A previous study showed promising results for gadofosveset-trisodium as a lymph node magnetic resonance imaging (MRI) contrast agent in rectal cancer. The aim of this study was to prospectively confirm the diagnostic performance of gadofosveset MRI for nodal (re)staging in rectal cancer in a second patient cohort.

Methods: Seventy-one rectal cancer patients were prospectively included, of whom 13 (group I) underwent a primary staging gadofosveset MRI (1.

Magnetization transfer ratio: a potential biomarker for the assessment of postradiation fibrosis in patients with rectal cancer.

Objectives: Magnetization transfer-magnetic resonance imaging (MT-MRI) uses differences in the magnetization interaction of the free "unbound" water protons and the macromolecular-bound protons. The aim of this study was to evaluate whether the magnetization transfer ratio (MTR) may be used to identify fibrosis in patients with rectal cancer treated with chemoradiotherapy.

Materials And Methods: This study was part of a rectal cancer imaging study, which was approved by the local institutional review board.

Diffusion-weighted MR imaging in primary rectal cancer staging demonstrates but does not characterise lymph nodes.

Objectives: To evaluate the performance of diffusion-weighted MRI (DWI) for the detection of lymph nodes and for differentiating between benign and metastatic nodes during primary rectal cancer staging.

Methods: Twenty-one patients underwent 1.5-T MRI followed by surgery (± preoperative 5 × 5 Gy).