msi mss crc in a patient case report

MSI is the “mutant” state where the MMR pathway is non-functional. MSI-H CRC is about 15% of all CRC and about 4% of stage 4 CRC.The good news is that this subset of CRC can be treated with a kind of treatment known as immunotherapy, which can be curative. How to know if your tumor is MSS or MSI from a pathology report

Full Answer

What are MSI and MSS in colorectal cancer?

If you’re a colorectal cancer patient, you might have seen the acronyms “MSI” and “MSS” in reference to tumor testing. Colorectal cancer tumors are often referred to as having an “MSI status,” meaning they will either be MSI or MSS – they will not be both.

Does MSI-or MSS-CRC have more CD4+ TILs?

Also, De Smedt et al(36) used IHC to demonstrate that there were no significant differences in the number of CD4(+) TILs in MSI- or MSS-CRC; however, Boissière-Michot et al(37) reported that the density of CD4(+) TILs was increased in MSI-CRC compared with MSS-CRC.

How do I find clinical trials for my MSS tumor?

If you’re a late-stage patient with an MSS tumor, use our Late-Stage MSS CRC Trial Finder – a clinical trial search tool curated by patients.

Do ICIS work for dMMR/MSI-H tumors in CRC?

In general, dMMR/MSI-H tumors in CRC are thought to respond to ICIs due to their highly immunogenic nature (14).

What is MSI and MSS?

The instability of one site is called low microsatellite instability (MSI-L), and the instability of two or more sites is called high microsatellite instability (MSI-H). The instability of all five sites is called microsatellite instability (MSS).

What does MSS mean in cancer?

In some cancer patients, the MMR process works well. For these people, the cancer cells are proficient in mismatch repair (pMMR) and their tumor cells have the same number of repeats as. in their healthy cells. This is also referred to as microsatellite stable or MSS.

What is a CRC patient?

Colorectal cancer, or CRC, is a disease of the colon or rectum, which are parts of the digestive system. Unlike most cancers, colorectal cancer is often preventable with screening and highly treatable when detected early.

What is MSS status?

“In the MSS group, which is most everybody, they don't work so well.” MSI status means there is a high amount of instability in a tumor, which occurs as a result of when genes that regulate DNA, also called mismatch repair (MMR) genes, do not correct errors in DNA as the cancer cells divide.

What is MSI status in cancer?

A change that occurs in certain cells (such as cancer cells) in which the number of repeated DNA bases in a microsatellite (a short, repeated sequence of DNA) is different from what it was when the microsatellite was inherited.

What does MSI mean in medical terms?

MSI stands for microsatellite instability. MSI-high is a subset of colon cancer in which the tumor cells have a lot of instability. These cancer cells look and behave in an abnormal way.

What is CRC diagnosis?

Colorectal cancer (CRC) is a common and lethal disease. It is estimated that approximately 151,030 new cases of large bowel cancer are diagnosed annually in the United States [1], of which approximately 106,180 arise from colon and the remainder from the rectum.

How is CRC staged?

The earliest stage colorectal cancers are called stage 0 (a very early cancer), and then range from stages I (1) through IV (4). As a rule, the lower the number, the less the cancer has spread. A higher number, such as stage IV, means cancer has spread more. And within a stage, an earlier letter means a lower stage.

Why do we do CRC test?

Order your own Colorectal Cancer Screening Blood Test (BeScreened-CRC) BeScreened-CRC is a blood-based test intended for people 45-85 years of age only and at average risk for colorectal cancer who are unable or unwilling to be screened by colonoscopy or fecal-based tests (with or without DNA).

What is an MSI report?

Microsatellites are regions of repeated DNA that change in length (show instability) when mismatch repair is not working properly. MSI testing looks at the length of certain DNA microsatellites from the tumor sample to see if they have gotten longer or shorter as a measure of instability.

What does MSI positive mean?

A high-positive MSI (MSI-H) result may indicate that the gene repair problem is related to the development of the cancer, and that the patient may have hereditary nonpolyposis colorectal cancer (HNPCC) (also known as Lynch syndrome.)

What does MSI low mean?

MSI-low is an intermediate type between MSI-high and MSS in esophagogastric junction adenocarcinoma.

Introduction

Colorectal cancer (CRC) is the third most commonly diagnosed and fourth most deadly cancer in the world ( 1 ).

Case Description

A 54-year-old female was admitted with right upper abdominal pain, and was diagnosed with right-sided colon cancer through electronic colonoscopy. The diagnosis was further confirmed by biopsy in February 2018.

Discussion

In this case report, an MSS and BRAF V600E mCRC patient responded well to immunotherapy and bevacizumab, achieving a PFS exceeding 17 months, which allows us to reconsider the therapeutic effect of immunotherapy on such patients.

Data Availability Statement

The original contributions presented in the study are included in the article/ Supplementary Material. Further inquiries can be directed to the corresponding authors.

Ethics Statement

The studies involving human participants were reviewed and approved by Research Ethics Committee of the First Affiliated Hospital of Guangzhou University of Chinese Medicine (ZYYEC-ERK [2021]016). The patients/participants provided their written informed consent to participate in this study.

Author Contributions

Study conception and design: XwH, CF, and JtL. Data acquisition: ZX, TZ, and JjL. Manuscript writing: CF, XH, and YZ. Literature review: DN and ML. All authors have read and approved the manuscript before submission and agreed to be responsible for all aspects of this work. All authors contributed to the article and approved the submitted version.

Funding

This study was supported by the Guangzhou Science and Technology Bureau (201904010396) and the National Natural Science Foundation of China (81573780).

Abstract

Cutaneous metastases of colorectal cancer (CRC) are rare, occurring in 0.7% to 5% of cancer patients. Furthermore, the molecular subtypes of cutaneous metastasis of CRC are unclear. Here, we present a rare case of cutaneous metastasis of high-frequency microsatellite instability (MSI-high)/BRAFV600E-mutant cecum cancer.

Background

Colorectal cancer (CRC) is a common malignancy worldwide and is one of the leading causes of cancer-related deaths. More than 10% of patients with CRC have metastases at the time of diagnosis. CRC commonly metastasizes to the regional lymph nodes, lungs, liver, and peritoneum, but cutaneous metastases are rare.

Case presentation

A 77-year-old woman presented at the outpatient clinic with a subcutaneous mass on her left back (Fig. 1 a, b). She experienced severe weight loss and loss of appetite a few months before visiting the outpatient clinic.

Conclusions

Cutaneous metastasis of cancer is rare, occurring in 0.7%–5% of cancer patients [1]. Higher rates of cutaneous metastasis occur in melanomas, breast and lung cancers, and mucosal carcinomas of the head and neck [2]. The incidence of cutaneous metastasis of CRC is only 2.3% [3].

Availability of data and materials

The data that support the findings of this study are available from the corresponding author, TY, upon reasonable request.

Abbreviations

18F-fluorodeoxyglucose-positron emission tomography/computed tomography, XELOX + BEV: capecitabine + oxaliplatin + bevacizumab, MMR: mismatch repair

Acknowledgements

We thank Dr. Hideki Noda for providing cutaneous metastasis information. We would like to thank Editage ( www.editage.jp) for the English language editing.