Objective:

To report a case of microinvasive cervical squamous cell carcinoma with endometrial spread that was misdiagnosed as high-grade squamous intraepithelial lesion (HSIL) during conization.

Approach:

• Case Presentation: A 56-year-old postmenopausal woman was referred after high-risk HPV positivity and cytology showing atypical squamous cells that could not rule out HSIL. Colposcopy-directed biopsy and subsequent deep cervical conization indicated HSIL/CIN grade 3 with glandular involvement, but no definite invasive carcinoma was identified. Due to concerns about residual disease, the patient underwent an extrafascial total hysterectomy.

Key Findings:

• Final pathology revealed HSIL with a microinvasive squamous cell carcinoma focus measuring less than 0.5 mm and superficial endometrial spread.
• Immunohistochemistry confirmed the cervical origin of the neoplasm, excluding primary endometrial disease.
• At 6 months post-surgery, the patient was disease-free and tested negative for HPV.

Interpretation:

Conization may underestimate invasive disease in postmenopausal women, particularly with cervical atrophy and glandular involvement. Immunohistochemistry is crucial for distinguishing cervical neoplasia from primary endometrial lesions.

Limitations:

• The findings are based on a single patient case, which limits the generalizability of the results.
• The diagnostic challenges presented by cervical atrophy in postmenopausal women may not apply universally.

Conclusion:

This case highlights the importance of thorough evaluation of cervical lesions in postmenopausal women and the role of immunohistochemistry in accurate diagnosis.