No abstract

Adenosquamous carcinoma of the breast (ASBC) is a rare variant of metaplastic breast cancer with both glandular as well as squamous differentiation. Their lack of distinct imaging characteristics, sometimes subtle histological characteristics and overlapping features with other benign lesions pose a diagnostic challenge. Unlike other forms of metaplastic breast cancer, low-grade adenosquamous carcinoma (LGAC) tends to follow an indolent course with favourable prognosis. We reviewed eight cases of LGAC in our institution from June 2005 to March 2014. In six cases, LGAC was only found after excisional biopsy. In our patients, LGAC frequently co-existed with other forms of breast pathology. Two patients had incidental findings of LGAC alongside their primary malignant tumour (adenoid cystic carcinoma and invasive ductal carcinoma in one, four foci between 0.5 and 4.0 mm within a radial sclerosing lesion adjacent to a malignant phyllodes tumour in the other). A further four patients had LGAC within a complex sclerosing lesion. One patient had a focus of LGAC within a fibroadenoma. One had a focus of LGAC within a benign phyllodes tumour. None of the patients had evidence of nodal involvement. A high degree of suspicion is recommended as such lesions tend to be incidental histological findings within benign tumours or within complex sclerosing lesions. Although the risk of nodal and distant metastasis is low, the potential for local recurrence necessitates aggressive local excision with margin clearance. The role of axillary dissection has yet to be defined and routine sentinel node biopsy and axillary clearance may not be necessary in view of rarity of nodal metastasis in literature. Benefit from adjuvant radiotherapy or chemotherapy is not clearly defined. All eight patients in our study have shown no evidence of recurrence after definitive surgery but longer periods of surveillance is required.

Mucinous epithelial ovarian cancer has a poor prognosis in the advanced stages and responds poorly to conventional chemotherapy. We aim to elucidate the clinicopathological factors and incidence of HER2 expression of this cancer in a large Asian retrospective cohort from Singapore. Of a total of 133 cases, the median age at diagnosis was 48.3 years (range, 15.8–89.0 years), comparatively younger than western cohorts. Most were Chinese (71%), followed by Malays (16%), others (9.0%), and Indians (5%). 24% were noted to have a significant family history of malignancy of which breast and gastrointestinal cancers the most prominent. Majority of the patients (80%) had stage I disease at diagnosis. Information on HER2 status was available in 113 cases (85%). Of these, 31 cases (27.4%) were HER2+, higher than 18.8% reported in western population. HER2 positivity appeared to be lower among Chinese and higher among Malays patients (p = 0.052). With the current standard of care, there was no discernible impact of HER2 status on overall survival. (HR = 1.79; 95% CI, 0.66–4.85; p = 0.249). On the other hand, positive family history of cancer, presence of lymphovascular invasion, and ovarian surface involvements were significantly associated with inferior overall survival on univariate and continued to be statistically significant after adjustment for stage. While these clinical factors identify high risk patients, it is promising that the finding of a high incidence of HER2 in our Asian population may allow development of a HER2 targeted therapy to improve the management of mucinous ovarian cancers.