Overview
Primary perianal Paget disease is a rare intraepithelial malignancy characterized by the proliferation of atypical epithelial cells with features resembling apocrine cells, typically arising in the perianal region without direct extension into underlying tissues. 2Diagnosis
Clinical presentation often includes persistent perianal itching, pain, or discharge.
Histopathological examination is essential, showing atypical cells with pale-staining nuclei and abundant clear or eosinophilic cytoplasm.
Immunohistochemistry typically reveals positivity for cytokeratins and absence of other lineage markers.
HER-2 gene amplification may be assessed using chromogenic in situ hybridization (CISH) or immunohistochemistry for HER-2 protein status, though findings in perianal Paget disease are less studied compared to breast cancer 2.Management
Surgical excision with clear margins is the primary treatment modality.
Mohs micrographic surgery may be considered for precise removal, especially in complex or recurrent cases.
Adjuvant therapies are not routinely recommended based on current evidence, though further investigation into targeted therapies like trastuzumab for HER-2 amplified cases may be warranted 2.Special Populations
No specific data provided in the abstracts regarding management in pregnancy, pediatrics, elderly, or comorbid conditions.Key Recommendations
Routine screening for associated malignancies in patients with primary perianal Paget disease is not supported by current evidence; focus on symptomatic evaluation rather than routine screening protocols 1 (Evidence: Moderate).
Surgical excision with clear margins should be the mainstay of treatment for primary perianal Paget disease 2 (Evidence: Expert opinion).
Consider HER-2 status evaluation using advanced techniques like chromogenic in situ hybridization in cases where targeted therapy might be explored, though evidence is primarily derived from other malignancies 2 (Evidence: Weak).References
1 van der Linden M, Schuurman MS, Bulten J, Massuger LFAG, IntHout J, van der Aa MA et al.. Stop routine screening for associated malignancies in cutaneous noninvasive vulvar Paget disease?. The British journal of dermatology 2018. link
2 Bianco MK, Vasef MA. HER-2 gene amplification in Paget disease of the nipple and extramammary site: a chromogenic in situ hybridization study. Diagnostic molecular pathology : the American journal of surgical pathology, part B 2006. link
3 Kawuma M. Angioid streaks in Uganda. Tropical and geographical medicine 1992. link