Fit-for-Purpose Ki-67 Immunohistochemistry Assays for Breast Cancer.

New therapies are being developed for breast cancer, and in this process, some "old" biomarkers are reutilized and given a new purpose. It is not always recognized that by changing a biomarker's intended use, a new biomarker assay is created. The Ki-67 biomarker is typically assessed by immunohistochemistry (IHC) to provide a proliferative index in breast cancer. Canadian laboratories assessed the analytical performance and diagnostic accuracy of their Ki-67 IHC laboratory-developed tests (LDTs) of relevance for the LDTs' clinical utility. Canadian clinical IHC laboratories enrolled in the Canadian Biomarker Quality Assurance Pilot Run for Ki-67 in breast cancer by invitation. The Dako Ki-67 IHC pharmDx assay was employed as a study reference assay. The Dako central laboratory was the reference laboratory. Participants received unstained slides of breast cancer tissue microarrays with 32 cases and performed their in-house Ki-67 assays. The results were assessed using QuPath, an open-source software application for bioimage analysis. Positive percent agreement (PPA, sensitivity) and negative percent agreement (NPA, specificity) were calculated against the Dako Ki-67 IHC pharmDx assay for 5%, 10%, 20%, and 30% cutoffs. Overall, PPA and NPA varied depending on the selected cutoff; participants were more successful with 5% and 10%, than with 20% and 30% cutoffs. Only 4 of 16 laboratories had robust IHC protocols with acceptable PPA for all cutoffs. The lowest PPA for the 5% cutoff was 85%, for 10% was 63%, for 20% was 14%, and for 30% was 13%. The lowest NPA for the 5% cutoff was 50%, for 10% was 33%, for 20% was 50%, and for 30% was 57%. Despite many years of international efforts to standardize IHC testing for Ki-67 in breast cancer, our results indicate that Canadian clinical LDTs have a wide analytical sensitivity range and poor agreement for 20% and 30% cutoffs. The poor agreement was not due to the readout but rather due to IHC protocol conditions. International Ki-67 in Breast Cancer Working Group (IKWG) recommendations related to Ki-67 IHC standardization cannot take full effect without reliable fit-for-purpose reference materials that are required for the initial assay calibration, assay performance monitoring, and proficiency testing.

Predictors of Outcome in Mammary Adenoid Cystic Carcinoma: A Multi-Institutional Study.

Mammary adenoid cystic carcinoma (ACC) is a rare subtype of breast cancer with a favorable prognosis. Here we report on predictors of outcome based on a detailed morphologic review and analysis of 108 mammary ACC. Sixty-four tumors (59.2%) were pure conventional ACC, 23 (21.3%) were pure basaloid ACC. Follow-up was available for 87 patients (median: 51 mo). Eighteen patients (20.7%) developed recurrence: 7 (8%) had local recurrence and 14 (16%) had distant metastasis. Two patients died of disease, 1 died of an unrelated cause, 14 were alive with disease (including 8 in palliative care), and 70 (80.5%) were alive with no evidence of disease. Of 90 patients with known lymph node (LN) status 9 (10%) had nodal involvement (all with basaloid ACC). Distant metastases in patients with predominantly basaloid ACC compared with pure conventional ACC were more common (40% vs. 7.7%) and occurred earlier (22 vs. 84 mo). The following factors were found to be predictive of recurrence-free survival: positive margin, Nottingham grade, neovascularization, basaloid component, perineural invasion, lymphovascular invasion, >30% solid growth, necrosis and LN involvement; the first 3 remained statistically significant on multivariate analysis. Factors predictive of distant disease-free survival were neovascularization, Nottingham grade, lymphovascular invasion, solid component >50%, LN involvement, basaloid component >50%, tumor necrosis, perineural invasion, and final margin. Only neovascularization remained statistically significant on multivariate analysis. Basaloid ACC is an aggressive variant of mammary ACC with more frequent nodal involvement and higher incidence of distant spread. LN staging should be performed for all mammary basaloid ACC.

Diagnostic pitfalls in fine needle aspiration biopsy of the spleen.

Fine needle aspiration (FNA) of the spleen is rarely performed, due to fear of procedure complications. The objective of this study is to review the cytologic diagnoses of aspiration biopsy of the spleen performed in a cancer center. Archival material (9-year period) was reviewed and correlated with histologic and ancillary test results, when available.Forty-one splenic FNA specimens were identified. There were no reported procedure complications. Nineteen cases were diagnosed as malignant. Of these, 11 were lymphomas. Nineteen cases were diagnosed as benign. There was one false-negative case and four false-positive cases. Primary splenic neoplasms were rare and misinterpreted as malignant. It is important to be familiar with the normal cytology of this uncommonly aspirated organ in order to successfully identify neoplastic and malignant processes. The use of ancillary studies is important in the definitive classification of benign and malignant splenic lesions.

Grg1 acts as a lung-specific oncogene in a transgenic mouse model.

Groucho proteins are transcriptional corepressors that are recruited to gene regulatory regions by numerous transcription factors. Long isoforms, such as Grg1, have all the domains of the prototype Drosophila Groucho. Short Groucho proteins, such as Grg5, have only the amino-terminal Q and G/P domains. We generated Grg1 and Grg5 transgenic mice and found that Grg1 overexpression induces lung adenocarcinoma, whereas Grg5 overexpression does not. Coexpression of Grg5 with Grg1 reduces tumor burden. Grg1 and Grg5 both diminish p53 protein levels; however, only Grg1 overexpression induces elevated levels of ErbB1 and ErbB2 receptor tyrosine kinases. The molecular and biological changes that accompany tumor progression in Grg1 transgenic mice closely reiterate events seen in human lung cancer. We also found that within a human lung tumor tissue array, a significant number of carcinomas overexpress Grg1/TLE1. Our data suggest that Grg1 overexpression contributes to malignancy in human lung cancers.

Fine needle aspiration biopsy of primary mucinous carcinoma of the skin: a case report.

BACKGROUND: Primary mucinous carcinoma of the skin is a rare neoplasm of sweat gland origin. To date there are only 2 case reports in English describing its features on fine needle aspiration biopsy (FNAB). We describe an additional case and review the literature regarding this entity. To the best of our knowledge, this is the first reported case with a sentinel lymph node biopsy. CASE: A 78-year-old woman presented with a 3-cm left scalp mass at an outside institution. Following incomplete excision, multiple subcentimeter nodules developed in the skin adjacent to the biopsy site. FNAB of the nodules confirmed a recurrence of mucinous carcinoma. Clinical examination and extensive radiographic studies did not reveal primary disease elsewhere, thus supporting a diagnosis of primary mucinous carcinoma of the skin. At the time of wide excision of the residual tumor, sentinel lymph node biopsy revealed a single focus of micrometastasis. The patient declined adjuvant therapy and was disease free 6 months after the initial diagnosis. CONCLUSION: Cutaneous mucinous carcinoma is a tumor characterized by bland histocytologic features and abundant extracellular pools of mucin. Without a high index of suspicion, this rare entity may be overlooked or misdiagnosed. Numerous benign and malignant mucin-producing primary and secondary mimics exist, and immunohistochemistry offers limited benefits in differentiating them. Cytologic diagnosis of primary mucinous carcinoma of the skin is possible; however, correlation of clinical, radiologic and pathologic features is necessary to arrive at an accurate diagnosis.

Skp2 gene copy number aberrations are common in non-small cell lung carcinoma, and its overexpression in tumors with ras mutation is a poor prognostic marker.

PURPOSE: Skp2 plays a critical role in cell cycle progression, especially at the G(1)-S transition, putatively through its control of several cell cycle regulator proteins. The Skp2 gene is located on a region of chromosome 5p that is commonly overrepresented in lung cancer. The present study aimed to evaluate Skp2 abnormalities and their prognostic value in non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: In total 16 NSCLC cell lines and 163 primary tumors were included in studies to measure Skp2 relative gene copy number, mRNA abundance, and protein level. The tumors were also evaluated for p27 protein expression level and ras mutation. These values were correlated with the clinical and pathological features of the patients. RESULTS: Skp2 relative gene copy number aberrations were found in 88 and 65% of NSCLC cell lines and primary tumors, respectively. Overrepresentation was especially common among squamous cell carcinoma (74%). Both gene copy overrepresentation (13%) and loss (35%) were found in adenocarcinoma. Skp2 relative gene copy number was significantly correlated with mRNA and protein levels, but none of these were correlated with p27 protein levels. Neither high Skp2 protein expression nor ras mutation was prognostically significant. In NSCLCs with ras mutation, however, high Skp2 protein expression was a significant independent poor prognostic marker. CONCLUSION: There appears to be a synergistic interaction between high Skp2 protein expression and ras mutation with negative impact on the survival of NSCLC patients.

Fine needle aspiration of renal cortical lesions in adults.

The role of fine needle aspiration (FNA) biopsy of renal cortical lesions was controversial in the past because the result of the FNA did not affect clinical management. All renal cortical lesions, except metastasis, were subject to surgical resection. However, with the advances in neoadjuvant targeted therapies, knowledge of the renal cortical tumor histological subtype is critical for tailoring clinical trials and follow-up strategies. At present, there are clinical trials involving the use of novel kinase inhibitors for conventional (clear cell) and papillary renal cell carcinoma. We studied 143 consecutive cases of renal cortical lesions, evaluated after radical or partial nephrectomies over a 2-year period. An air-dried smear and a Thinprep® slide were prepared in all cases. The slides were Diff-Quick and Papanicolaou stained, respectively. The cytology specimens were reviewed and the results were then compared with the histologic diagnosis. Cytology was highly accurate to diagnose conventional RCC, while the accuracy for papillary RCC, chromophobe RCC, and papillary urothelial carcinoma was much lower. Our results indicate that ancillary studies might have an important role in the subclassification of renal cortical neoplasms for targeted treatment.

Vaginal solitary fibrous tumor: a case report with recurrence after incomplete excision.

OBJECTIVE: Primary solitary fibrous tumors (SFTs) of the female genital tract are exceedingly rare. We report a spindle cell tumor of the vagina with features consistent with a SFT in a 52-year-old woman. MATERIALS AND METHODS: The original tumor was studied with the appropriate panel of immunohistochemical stains. The first recurrence of the tumor was 10 months after its original incomplete excision, and a second recurrence occurred 29 months later. Both recurrences were analyzed using the same immunohistochemical panel. RESULTS: After considering several related differential diagnoses, the diagnosis of SFT was made based on the morphological and immunophenotypic features. CONCLUSION: To the best of our knowledge, this is the third case of vaginal SFT in the English literature, with 2 recurrences after incomplete excision.

Fine-needle aspiration cytology of mammary adenomyoepithelioma: a study of 12 patients.

BACKGROUND: Adenomyoepithelioma (AME) of the breast is a rare neoplasm that is characterized by a biphasic proliferation of epithelial and myoepithelial cells. Incomplete excision of this lesion is associated with a greater risk of recurrence. Although the histology of AME is well characterized, its cytomorphology has not been assessed in a large series. METHODS: The authors conducted a retrospective evaluation of cytologic findings in fine-needle aspiration biopsy (FNAB) material from 12 patients with histologically proven benign AMEs of the breast. RESULTS: All aspirates were moderately to highly cellular with large clusters composed of epithelium and myoepithelium. The myoepithelium was admixed with the ductal cells or was present as naked bipolar nuclei in 75% of samples. Small clusters or dispersed myoepithelial cells with epithelioid morphology were also present and showed intranuclear and intractyoplasmic vacuoles in one-third of samples. Mild-to-moderate nuclear atypia was noted in some samples, but no necrosis or mitoses were seen. None of the patients were diagnosed originally with AME: Two tumors were classified as benign and consistent with fibroadenoma, 6 tumors were atypical, 2 tumors were suspicious for carcinoma, and 2 tumors were positive for malignant cells. CONCLUSIONS: Because of the varied histology of AME, cytologic diagnosis of this neoplasm can be very challenging. Accurate identification of the myoepithelium is crucial to avoid misinterpretation as carcinoma. Conservative diagnosis and further histologic evaluation is recommended for these patients.

Immunophenotypic diversity of endometrial adenocarcinomas: implications for differential diagnosis.

Many endometrial adenocarcinomas, particularly those of endometrioid type, express estrogen receptors (ERs), progesterone receptors (PRs), and vimentin. This typical immunophenotype is frequently considered a standard against which others are compared when immunohistochemistry is used for differential diagnosis. We tested large numbers of endometrial cancers, enriched for high-grade tumors, to determine whether this reported immunophenotype was valid and whether expression differences between types of endometrial carcinoma could be exploited for diagnostic purposes. Immunohistochemical stains were performed on the following types of endometrial cancers using established methodology: International Federation of Gynecology and Obstetrics (FIGO) grades 1 and 2 endometrioid-42; FIGO grade 3 endometrioid-40; serous-24; clear cell-11; carcinosarcoma-9. In total, 92% of serous carcinomas expressed p16 strongly compared to weak-to-moderate expression of p16 in 7-67% of other tumors (FIGO grades 1 and 2 carcinoma and carcinosarcoma, respectively). A total of 84% of FIGO grades 1 and 2 carcinomas expressed ER compared to 9-54% of other tumors (clear cell and serous carcinomas respectively); 83% of FIGO grades 1 and 2 expressed PR compared to 11-54% of other carcinomas (carcinosarcoma and serous carcinoma, respectively). Most carcinomas were negative for monoclonal carcinoembryonic antigen (mCEA), and those that were positive showed mostly only focal membrane expression. Vimentin was expressed in nearly every tumor. Most tumors were diffusely vimentin positive, but a large range of expression patterns, from focal to diffuse and from weak to strong, was noted. Only 70% of FIGO grades 1 and 2 endometrioid carcinomas and 26% of grade 3 endometrioid carcinomas possessed the reportedly characteristic endometrial cancer immunophenotype p16 (-), ER (+), PR (+), mCEA (-), and vimentin (+). Endometrial cancers demonstrate substantial immunophenotypic diversity that remained apparent even within groups of similar histologic subtype and grade. ER, PR, and p16 expression was more illustrative of tumor type and degree of differentiation than they were of endometrial origin. In contrast, the vimentin-positive/CEA-negative phenotype remained the most constant among all endometrial cancers.

Perivascular epithelioid cell tumor of the orbit: a case report and review of the literature.

We present a unique case of a perivascular epithelioid cell tumor (PEComa) in the orbit of a 9-year-old female patient. The entity of PEComas has been described only recently. Characteristic histologic features and an immunohistochemical profile of negativity for epithelial markers and positivity for melanogenesis-related markers define the tumors. In children and young adults, this tumor has a predilection for the falciform ligament and ligamentum teres of the liver. It is associated with, but not exclusive to, tuberous sclerosis. To the best of our knowledge, this is the first reported case of a PEComa of the orbit in a child or adult. The main differential diagnoses for this melanin pigment-producing lesion include melanoma and pigmented paraganglioma. The histologic features, immunohistochemical profile, ultrastructural studies, and molecular studies led us to favor a diagnosis of PEComa. The prognosis of this entity is undetermined due largely to the small number of reported cases.

Primary extranodal marginal zone B-cell lymphoma of MALT type of the endometrium.

BACKGROUND: Only one case of primary extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) of the endometrium has been previously reported. CASE: A 65-year old patient presented with postmenopausal bleeding. She was found to have endometrial polyps. The endometrial curettings showed a dense lymphoid infiltrate that was suggestive of a lymphoproliferative disorder. Histological examination of the total abdominal hysterectomy revealed primary extranodal marginal zone B-cell lymphoma (MALT-type lymphoma) of the endometrium. The diagnosis was supported by morphology, immunohistochemistry, and molecular analysis. CONCLUSIONS: Extranodal MALT lymphoma of the endometrium is exceptionally rare although the female genital tract is rich in mucosa and the presence of MALT tissue has been previously described. The diagnosis of lymphoproliferative disorder in this case was initially made on endometrial curettings. Although most lymphoid aggregates within endometrial curettings are due to reactive conditions such as endometritis, the possibility of lymphoma must be kept in mind when dense lymphoid aggregates or atypical lymphoid cells are present in the curettings.

Precursor B-cell lymphoblastic lymphoma of the ovaries: an immunohistochemical study and review of the literature.

A 46-year-old woman presented with increasing abdominal girth. Investigations revealed bilateral ovarian tumors but no evidence of systemic disease. A total abdominal hysterectomy and bilateral salpingo-oophorectomy were performed. There was no evidence of extraovarian tumor at the time of the operation. A diagnosis of precursor B cell lymphoblastic lymphoma was established by histologic examination, immunohistochemical staining, and molecular analysis. After a 6-month follow-up, there was evidence of focal bony involvement that improved after chemotherapy. Although non-Hodgkin's lymphoma may involve the female genital tract, particularly the ovaries, primary ovarian lymphoma is rare and its definition controversial. To the best of our knowledge, this is only the third reported case of a primary lymphoblastic lymphoma of the ovary.

Juvenile xanthogranuloma of the nose.

Juvenile xanthogranuloma is a type of non-Langerhans cell histiocytosis that occurs most frequently in infants and children. It is usually asymptomatic and can present as either a cutaneous or extracutaneous lesion. The present case is believed to be the first reported in the English literature of juvenile xanthogranuloma presenting as an ulcerated bleeding lesion on the dorsum of the nose.

Le xanthogranulome juvénile est un type d'histiocytose non langerhansienne qui affecte davantage les nourrissons et les enfants. Il est en général asymptomatique et peut se manifester par une lésion cutanée ou extracutanée. Le cas de xanthogranulome juvénile présenté ici serait le premier à avoir été signalé dans la littérature de langue anglaise sous la forme d'une lésion ulcérée sanguinolente au niveau de l'arête du nez.