Cutaneous metastasis of cecum cancer with MSI-high and BRAFV600E mutation: a case report
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Published on: February 10, 2023
Kosuke Yunoki1, Takuya Yano2, Masanori Yoshimitsu1
1Department of Surgery, Hiroshima City Hiroshima Citizens Hospital, 7-33 Motomachi, Naka-ku, Hiroshima, 730-8518, Japan.
Background:
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.
Case Presentation:
A 77-year-old woman presented at the outpatient clinic with a subcutaneous mass on her left back. An excisional biopsy was performed and metastatic cutaneous adenocarcinoma was diagnosed. A computed tomography scan of the thorax and abdomen showed thickening of the cecum wall, the presence of pericolic lymph nodes, multiple masses in the liver, and a single nodule in the right lung. Right colectomy with D2 lymphadenectomy and functional end-to-end anastomosis was performed because of the almost-complete intestinal obstruction. The expression of KRAS wild type, BRAFV600E mutation, and MSI-high was detected in the cecum cancer using molecular pathological examination. She received chemotherapy with XELOX + BEV regimen (capecitabine + oxaliplatin + bevacizumab). After four administrations, a computed tomography scan showed reduction of distant metastases, which suggested partial response.
Conclusions:
We encountered a rare case of cutaneous metastasis of MSI-high and BRAFV600E-mutant cecum cancer. In the future, it will be necessary to accumulate more cases to identify clinical features and more effective treatments for CRCs with cutaneous metastasis.
Insights
This study reports a rare case of cutaneous metastasis in a patient with high-frequency microsatellite instability (MSI-high) and BRAFV600E-mutant cecum cancer. Further research is needed to understand clinical features and treatments for such rare colorectal cancer (CRC) presentations.
Area of Science:
- Oncology
- Gastroenterology
- Dermatology
Background:
- Cutaneous metastases from colorectal cancer (CRC) are infrequent, affecting 0.7%–5% of patients.
- The molecular characteristics of CRC cutaneous metastases remain largely undefined.
- This case highlights a rare instance of MSI-high and BRAFV600E-mutant cecum cancer with skin involvement.
Purpose of the Study:
- To document and analyze a rare case of cutaneous metastasis originating from a BRAFV600E-mutant and MSI-high cecum tumor.
- To contribute to the understanding of the molecular subtypes associated with CRC cutaneous metastases.
Main Methods:
- A case presentation of a 77-year-old female with a subcutaneous mass.
- Diagnostic procedures included excisional biopsy, CT scans, and molecular pathological examination (KRAS, BRAFV600E, MSI status).
- Treatment involved right colectomy followed by XELOX + BEV chemotherapy.
Main Results:
- Metastatic cutaneous adenocarcinoma was diagnosed.
- The cecum cancer was characterized as MSI-high with a BRAFV600E mutation.
- The patient showed a partial response to XELOX + BEV chemotherapy, with reduced distant metastases.
Conclusions:
- This case represents a rare occurrence of cutaneous metastasis from MSI-high and BRAFV600E-mutant cecum cancer.
- Accumulating more cases is crucial for defining clinical features and optimizing treatments for CRCs with cutaneous metastasis.
- Further investigation into the molecular landscape of CRC with skin metastasis is warranted.
