Specific Biomarker Expression Patterns in the Diagnosis of Residual and Recurrent Endometrial Precancers After Progestin Treatment: A Longitudinal Study.

BACKGROUND: Conservative management with progestin is a treatment option for atypical hyperplasia (AH). However, pathologic diagnosis of residual/recurrent lesions is often problematic because of the profound morphologic changes induced by progestin and the lack of established diagnostic criteria for progestin-treated residual AH. METHODS: We conducted a longitudinal study of 265 endometrial biopsies from 54 patients with a history of AH on progestin therapy. Patient outcomes were divided into 3 categories after morphologic review and immunohistochemical staining with phosphatase and tensin homolog (PTEN) and paired box 2 (PAX2): (1) persistent or residual disease; (2) recurrent disease; (3) complete response. All specimens were classified into 3 categories based on morphology: (1) persistent/recurrent disease (nonresponse), (2) morphologically uncertain response, (3) optimally treated (complete response). The staining patterns of PTEN/PAX2 were tracked over time in individual patients and correlated with morphologic findings before and after progestin therapy. RESULTS: Our data showed that aberrant expression patterns of PTEN and/or PAX2 were identified in 48 (88.9%) of the 54 primary biopsies and persisted in persistent/recurrent AH across serial endometrial biopsies (n=99, P<0.00001), while normal PTEN and PAX2 expressions were consistently observed in optimally treated cases (n=84, P<0.00001). More importantly, follow-up biopsies that showed a morphologically uncertain response but a PTEN/PAX2 expression pattern identical to the initial biopsy were significantly correlated with persistent or recurrent disease (n=18, P=0.000182), as evidenced by areas with morphologic features diagnostic of AH on subsequent biopsy. CONCLUSIONS: Biomarker PTEN/PAX2 signatures offer a valuable diagnostic aid to identify residual AH in progestin-treated endometrial samples for which the biomarker status from preprogestin treated AH is known. The findings of this study are promising for a possible future change of diagnostic practice.

Significantly increased PELP1 protein expression in primary and metastatic triple-negative breast carcinoma: comparison with GATA3 expression and PELP1's potential role in triple-negative breast carcinoma.

PELP1 is a novel coregulator of nuclear hormone receptors and is implicated in playing a role in driving breast cancer and enhancing metastatic potential. The PELP1 protein expression and potential role of PELP1 in triple-negative breast carcinoma (TNBC) have not been well characterized. We investigated PELP1 expression by immunohistochemistry in primary and metastatic triple-negative tumors in human tissues and compared its expression with GATA-binding protein 3 (GATA3), a novel diagnostic marker for TNBC. We examined the expression of PELP1 and GATA3 in 70 primary TNBC cases and found that PELP1 had a significantly higher frequency of expression compared to GATA3 (96% versus 46%; P < .0001). The mean extent score of expression of PELP1 was also significantly higher than GATA3's expression (3.87 ± 0.07 versus 0.91 ± 0.15; P < .0001). PELP1 had stronger staining intensity than GATA3. Furthermore, PELP1 immunoreactivity was consistently maintained in paired primary and metastatic TNBC cases (100%). The frequency of PELP1 expression (100%) in metastatic triple-negative tumors was higher than that of GATA3 (40%) in the same tumors (P < .0001). These findings indicate that PELP1 is a much more sensitive marker than GATA3 for TNBCs. PELP1 may have diagnostic utility for metastatic TNBC in appropriate settings, such as history of primary TNBC in cases where the primary is negative for GATA3, mammaglobin, and GCDFP-15. The diffuse and strong nuclear immunoreactivity of PELP1 in most cases suggests that PELP1 may be a molecular target for the treatment of TNBC. We hope that this study will provide insights into the role of PELP1 in TNBC.

Decreased androgen receptor expression is associated with distant metastases in patients with androgen receptor-expressing triple-negative breast carcinoma.

To characterize prognostic values of androgen receptor (AR) in triple-negative (TN) breast cancers, we investigated AR expression status and levels, explored an association of AR expression with metastatic disease, and correlated AR expression with Ki-67 in TN invasive breast carcinomas. AR expression was analyzed with immunohistochemistry in 121 cases of TN tumors. Thirty-nine cases had distant metastatic disease and 82 had locoregional disease only. AR was positive in 38 (31.4%) of the 121 cases. Our results indicate that among the AR-positive TN tumors, distant metastases are significantly associated with lower expression of AR compared with cases with only locoregional disease, and that AR expression negatively correlates with Ki-67 expression. These findings suggest that decreased intratumoral AR expression may be predictive of distant metastatic disease and AR expression levels may have potential prognostic value in AR-expressing TN tumors.

Predictors of invasion and axillary lymph node metastasis in patients with a core biopsy diagnosis of ductal carcinoma in situ: an analysis of 255 cases.

The diagnosis of ductal carcinoma in situ (DCIS) using core biopsy does not ensure the absence of invasion on final excision. We performed a retrospective analysis of 255 patients with DCIS who had subsequent excision. Clinical, radiologic, and pathologic findings were correlated with risk of invasion and sentinel lymph node (SLN) metastasis. Of 255 patients with DCIS, 199 had definitive surgery and 52 (26%) had invasive ductal carcinoma (IDC) on final excision. Extent of abnormal microcalcification on mammography, and presence of a radiologic/palpable mass and solid type of DCIS were significantly associated with invasion on final excision. Sentinel lymph node biopsy was performed in 131 (65.8%) patients of whom 18 (13.4%) had metastasis. Size of IDC and extent of DCIS on final pathology were significantly associated with positive SLN. Micrometastasis and isolated tumor cells comprised majority (71.4%) of the metastases in DCIS. SLN biopsy should be considered in those with high risk DCIS.

Melanoma in a carcinoma ex pleomorphic adenoma of the parotid gland: a case report and putative histogenesis.

A rare example of melanoma arising in carcinoma ex pleomorphic adenoma is presented. The diagnosis, differential diagnosis, and putative histogenesis of the melanoma component are discussed.

Hormone receptor status rather than HER2 status is significantly associated with increased Ki-67 and p53 expression in triple-negative breast carcinomas, and high expression of Ki-67 but not p53 is significantly associated with axillary nodal metastasis in triple-negative and high-grade non-triple-negative breast carcinomas.

Triple-negative (TN) breast carcinoma is associated with a higher recurrence rate and shorter survival and lacks the benefit of specific therapy. TN tumors usually express high levels of Ki-67 and p53 that are considered prognostic markers for breast cancer. We compared Ki-67 and p53 expression between TN and high-grade non-TN invasive carcinomas in a total of 214 cases and investigated an association between their expression and axillary nodal metastasis in these tumors. Our findings demonstrate that TN tumors are associated with significantly higher expression of Ki-67 and p53 compared with non-TN tumors, which may contribute to the poorer prognosis in TN tumors. Hormone receptor negativity rather than HER2 negativity is associated with the significantly increased Ki-67 and p53 expression in TN tumors. Furthermore, a high expression level of Ki-67 but not p53 is more likely to be associated with axillary nodal metastasis in these cases.

Intratumoral expression level of epidermal growth factor receptor and cytokeratin 5/6 is significantly associated with nodal and distant metastases in patients with basal-like triple-negative breast carcinoma.

Triple-negative (TN) breast carcinoma, characterized by estrogen receptor, progesterone receptor, and HER2 negativity, is a group of aggressive tumors that can be further classified into 2 subtypes: basal-like, defined as CK5/6 and/or epidermal growth factor receptor (EGFR) positive by immunohistochemistry; and non-basal-like. Clinical characteristics and tumor profiles were analyzed in 105 cases of TN tumors. Among these cases, 35 had distant metastasis, 34 had axillary nodal metastasis only, and 36 were nodal negative. Our results indicate basal-like TN breast tumors with nodal and distant metastases are significantly associated with a higher intratumoral expression of EGFR and CK5/6 compared to those in the nodal negative group. High level of intratumoral EGFR and CK5/6 expression may play a role in development of nodal or distant metastases in patients with basal-like TN tumors and may be predictive of metastatic disease. Furthermore, EGFR targeted therapy may be potentially useful in the treatment of basal-like TN breast cancer.

Diagnostic utility of SALL4 in extragonadal yolk sac tumors: an immunohistochemical study of 59 cases with comparison to placental-like alkaline phosphatase, alpha-fetoprotein, and glypican-3.

Extragonadal yolk sac tumors (YSTs; primary and metastatic) are rare but are malignant germ cell tumors. Pathologic diagnosis of extragonadal YSTs can be challenging without immunohistochemical markers but markers used for diagnosing these tumors such as placental-like alkaline phosphatase (PLAP), alpha-fetoprotein (AFP), and glypican-3 lack adequate sensitivity and/or specificity. In earlier studies with gonadal germ cell tumors, SALL4 has been identified as a novel diagnostic marker for YSTs and other types of primitive germ cell tumors. Here, we investigated the diagnostic utility of SALL4 in 59 extragonadal YSTs (27 primary sacrococcygeal, 15 primary nonsacrococcygeal, and 17 metastatic) by immunohistochemical staining. We also compared SALL4 with PLAP, AFP, and glypican-3. In addition, we performed immunostains for pancytokeratin, epithelial membrane antigen, and OCT4 in these tumors. Our results showed that all 59 YSTs showed strong pancytokeratin staining (70% tumor cells in 1 case, >90% tumor cells in 58) and 10 (17%) of them also showed focal epithelial membrane antigen staining (<3% tumor cells). All 59 YSTs were negative for OCT4. Strong SALL4 staining was seen in all 59 YSTs (in more than 90% tumor cells in 54 and 70% to 85% tumor cells in 5 YSTs). Only 39 of 59 (66%) YSTs showed positive PLAP staining and the staining was often focal (in less than 30% tumor cells) (28 of 39 cases). Positive AFP staining was seen in the vast majority of YSTs (56 of 59 or 95%); however, 32 (54%) YSTs showed staining in less than 30% tumor cells. Although all 59 YSTs showed positive glypican-3 staining, 18 (30%) showed staining in less than 30% tumor cells, and additional 10 (17%) showed staining in between 30% and 60% tumor cells. In these 59 YSTs, the mean percentage of tumor cells stained with PLAP was 14% (range: 0% to 90%), with AFP 35% (range 0% to 95%), and with glypican-3 57% (range: 1% to 100%), whereas the mean percentage of tumor cells stained for SALL4 was 94% (range: 70% to 100%) (P<0.001). Our results indicate that SALL4 is a novel sensitive (100% sensitivity) diagnostic marker for extragonadal YSTs. SALL4 is a more sensitive marker than PLAP, AFP, or glypican-3 for extragonadal YSTs.

SALL4 is a novel sensitive and specific marker of ovarian primitive germ cell tumors and is particularly useful in distinguishing yolk sac tumor from clear cell carcinoma.

Ovarian primitive germ cell tumors (GCTs) are uncommon tumors and sometimes pose diagnostic challenges. Among them, yolk sac tumor (YST) poses the greatest diagnostic difficulty and can be mistaken for clear cell carcinoma (CCC). Current immunohistochemical markers such as alpha-fetoprotein (AFP), glypican-3, cytokeratin (CK) 7, and epithelial membrane antigen (EMA) used to distinguish YST from CCC lack adequate sensitivity and specificity. Here by immunohistochemistry, we investigated a novel marker SALL4 in 98 GCTs (29 YSTs, 18 dysgerminomas, 6 gonadoblastomas, 6 embryonal carcinomas, 15 immature and 12 mature teratomas, 7 carcinoid tumors, 3 strumal carcinoids, and 2 struma ovarii) with particular interest of exploring SALL4 to distinguish YST from CCC. One hundred sixty-three non-GCTs including 45 CCCs were also stained. We found that SALL4 is strongly positive in more than 90% tumor cells in all YSTs, dysgerminomas, gonadoblastomas, and embryonal carcinomas. Variable SALL4 staining is seen in 11 of 15 immature teratomas. All other GCTs included in this study are negative for SALL4. Except 3 CCCs with focal SALL4 staining (<15% tumor cells), SALL4 is negative in the remaining 160 non-GCTs. We also compared SALL4 with AFP, glypican-3, CK7, and EMA in all YSTs and CCCs. AFP and glypican-3 are positive in 24 (83%) and 20 (69%) YSTs, respectively, whereas 16 (35%) and 13(28%) CCCs show positive AFP and glypican-3 staining, respectively. Three (10%) and 4 (14%) YSTs show focal (<2% tumor cells) CK7 and EMA staining, respectively. CK7 and EMA are positive in all 45 CCCs but 3 (7%) and 1 (2%) cases show staining in less than 30% tumor cells, respectively. Our findings indicate that SALL4 is a novel sensitive and specific marker for ovarian primitive GCTs. SALL4 is particularly useful in distinguishing YST from CCC and better than AFP, glypican-3, CK7, and EMA.

False-positive sentinel lymph nodes in breast cancer patients caused by benign glandular inclusions: report of three cases and review of the literature.

We report 3 cases of sentinel lymph nodes (SLNs) containing benign glandular inclusions (BGIs) in patients with breast carcinoma that were initially misdiagnosed as metastatic carcinoma. The first case had an SLN with glandular elements adjacent to a squamous inclusion cyst, the second had an SLN with a single complex gland showing apocrine features, and the third had 2 SLNs, each containing rare glands lined by bland columnar cells and surrounded by thin, fibrous bands. All glandular elements were distinctly different from the corresponding invasive carcinoma. Immunostains for myoepithelial markers revealed smooth muscle myosin reactivity and scattered p63+ nuclei, indicating the presence of myoepithelial cells. Based on morphologic and immunohistochemical findings, a diagnosis of BGIs was established. Our case series report indicates that comparison with the morphologic features of primary breast carcinoma and using immunohistochemical analysis for myoepithelial markers are important ancillary tools in distinguishing BGIs from metastatic carcinoma.

Primary mucinous adenocarcinoma of the thymus: a case report and review of the literature.

Primary thymic mucinous adenocarcinoma is extremely rare; to our knowledge, only 2 cases have been reported to date. We describe a third case of primary mucinous adenocarcinoma of the thymus in a 41-year-old man who presented with an anterior mediastinal mass with subsequent metastasis to the lung. The initial diagnosis was of metastatic mucinous adenocarcinoma, but extensive clinical workup of the patient failed to reveal a primary tumor elsewhere in the body. The specific identification of mucinous adenocarcinoma as a primary thymic neoplasm can be difficult or impossible. Morphologic and immunophenotypic similarities to mucinous adenocarcinomas of the gastrointestinal tract can pose diagnostic challenges for surgical pathologists, especially in small biopsy specimens.

Immunohistochemical expression of beta-catenin in solitary fibrous tumors.

CONTEXT: Immunohistochemical staining for beta-catenin may be used as an indicator of the integrity of the Wnt signaling and beta-catenin degradation pathways. Among mesenchymal tumors, aberrant nuclear localization of beta-catenin is seen in desmoid-type fibromatoses but has not been described for solitary fibrous tumors that may mimic the former lesions, especially in small biopsy samples. OBJECTIVE: To study the immunohistochemical expression of beta-catenin in solitary fibrous tumors. DESIGN: We performed immunohistochemical staining for beta-catenin in 12 solitary fibrous tumors, one of which showed histologic features of malignancy. RESULTS: All the tumors showed strong and diffuse reactivity for beta-catenin. Four tumors (33%) showed nuclear staining for beta-catenin, whereas the remaining tumors showed either a membranous or mixed membranous and cytoplasmic pattern of staining. The only histologically malignant tumor of the group showed a mixed membranous and cytoplasmic pattern of staining for beta-catenin. CONCLUSIONS: Immunohistochemical staining for beta-catenin in solitary fibrous tumors does not show a consistent pattern, which may be due to differences in tumorigenesis. Larger studies with clinical follow-up are required for estimating the impact of the variable staining pattern on clinical behavior of these tumors.

Secondary syphilis: a histologic and immunohistochemical evaluation.

The usual method for detecting spirochetes in tissue sections is the silver stain; however, they are often difficult to detect due to marked background staining commonly seen with this technique. In certain clinical settings, such as neurosyphilis, congenital syphilis, and immunosuppressive conditions including human immunodeficiency virus (HIV) infection, a better method of detecting spirochetes in tissue sections is needed. We compare immunohistochemistry (IHC) with a monoclonal antibody to Treponema pallidum to silver staining in 19 biopsies from 17 patients with serologic evidence of secondary syphilis. IHC demonstrated a sensitivity of 71%, which was superior to the 41% sensitivity of the silver stain (p = 0.084). Furthermore, specificity was improved with IHC, as background artifacts were markedly reduced. Dermal spirochetes were visualized in all 12 positive cases, while epidermal organisms were seen in only eight cases. This finding lies contrary to accepted teaching that organisms are most commonly seen at the dermal epidermal junction. Of interest, perineural plasmacellular infiltrates were frequently seen in our cases (74%). Spirochetes were not seen in any of 14 control cases with similar histopathologic patterns. Although serologic studies remain the gold standard, IHC is more sensitive and specific than silver stain for detecting T. pallidum in biopsies of secondary syphilis.

Primary glomangioma of the liver: a case report and review of the literature.

Glomangiomas are a subset of glomus tumors that have a rich vascular network. Although a majority of the glomus tumors occur in the skin of the hand, they have also been reported in the deep soft tissue, bone, lungs, and gastrointestinal tract, especially the stomach. To our knowledge, only one such case has previously been reported primarily occurring in the liver. We report a case of a glomangioma primarily arising in the liver of a 57-year-old man who presented with right flank pain of several months' duration. A 3.0-cm hepatic mass was excised and consisted of numerous, small-to-medium branched vessels with the stroma containing small, round, regular cells with sharply outlined round-to-oval nuclei. Immunostains showed the tumor cells to be diffusely positive for vimentin and smooth muscle actin and to be focally positive for calponin. Collagen IV stained the pericellular matrix. The immunostain for CD34 highlighted the vascular network as well as outlined the tumor cells in many areas. Coexpression of actin and CD34 in glomus tumors, although unusual, has recently been reported in the literature. Despite its bland histology, the large tumor size and deep visceral location were suggestive of aggressive behavior; thus, a close clinical follow-up was recommended. The patient had an unremarkable postoperative course and has no evidence of metastatic disease 12 months after the procedure. An accurate diagnosis and an understanding the biology of this rare disease, especially in an unusual location, are crucial to its management.