SPRINGFIELD PATHOLOGY ASSOCIATES
Surgical Pathology Report
Patient: Robert Chen
MRN: MRN003
Date of Procedure: January 15, 2024
Date of Report: January 18, 2024
Specimen: Colon biopsy, sigmoid
CLINICAL HISTORY:
56-year-old male with rectal bleeding, change in bowel habits, and sigmoid mass
seen on colonoscopy.
GROSS DESCRIPTION:
Received in formalin labeled "sigmoid colon biopsy" are six fragments of tan-pink
tissue ranging from 0.2 to 0.4 cm in greatest dimension. All tissue submitted in
two cassettes.
MICROSCOPIC DESCRIPTION:
Sections show colonic mucosa with an invasive adenocarcinoma. The tumor is
moderately differentiated and consists of malignant glands infiltrating through
the muscularis mucosae into the submucosa. There is associated desmoplastic
stromal reaction and lymphovascular space invasion is identified.
The malignant glands show enlarged, hyperchromatic nuclei with prominent nucleoli
and increased mitotic activity. Areas of necrosis are present.
IMMUNOHISTOCHEMISTRY:
CK20: Positive
CDX2: Positive
CK7: Negative
MLH1: Retained nuclear expression
MSH2: Retained nuclear expression
MSH6: Retained nuclear expression
PMS2: Retained nuclear expression
MOLECULAR:
Microsatellite instability testing: Microsatellite stable (MSS)
DIAGNOSIS:
SIGMOID COLON, BIOPSY:
- INVASIVE MODERATELY DIFFERENTIATED ADENOCARCINOMA
- LYMPHOVASCULAR INVASION PRESENT
- TUMOR IS MICROSATELLITE STABLE
COMMENT:
This is a conventional colonic adenocarcinoma. Retained expression of mismatch
repair proteins (MLH1, MSH2, MSH6, PMS2) indicates microsatellite stable tumor.
Clinical correlation and staging studies recommended to determine extent of disease
and guide treatment decisions.
Pathologist: Dr. Elizabeth Morgan, MD
Board Certified Anatomic and Clinical Pathology
Date Signed: January 18, 2024