VEGFA Status as a Predictive Marker of Therapy Outcome in Metastatic Gastric Cancer Patients Following Ramucirumab-Based Treatment

Metastatic gastric cancer (mGC) often has a poor prognosis and may benefit from a few targeted therapies. Ramucirumab-based anti-angiogenic therapy targeting the VEGFR2 represents a milestone in the second-line treatment of mGC. Several studies on different cancers are focusing on the major VEGFR2 ligand status, meaning VEGFA gene copy number and protein overexpression, as a prognostic marker and predictor of response to anti-angiogenic therapy. Following this insight, our study aims to examine the role of VEGFA status as a predictive biomarker for the outcome of second-line therapy with Ramucirumab and paclitaxel in mGC patients. To this purpose, the copy number of the VEGFA gene, by fluorescence in situ hybridization experiments, and its expression in tumor tissue as well as the density of micro-vessels, by immunohistochemistry experiments, were assessed in samples derived from mGC patients. This analysis found that amplification of VEGFA concomitantly with VEGFA overexpression and overexpression of VEGFA with micro-vessels density are more represented in patients showing disease control during treatment with Ramucirumab. In addition, in the analyzed series, it was found that amplification was not always associated with overexpression of VEGFA, but overexpression of VEGFA correlates with high micro-vessel density. In conclusion, overexpression of VEGFA could emerge as a potential biomarker to predict the response to anti-angiogenic therapy.

De-Implementation of Axillary Staging and Radiotherapy in Low-Risk Breast Cancer Patients Aged 70-79 Years from Six Italian Cancer Institutes

In women aged ≥70 with low-risk breast cancer (BrC), some major international guidelines recommend against sentinel lymph node biopsy (for example, those from the Society of Surgical Oncology, U.S.) and post-lumpectomy radiotherapy (for example, those from the National Comprehensive Cancer Network, U.S.). We assessed the frequency of both procedures in six National Cancer Institutes (IRCCSs) in the North, the Centre, and the South of Italy. Data on tumour characteristics and treatment were obtained from each centre. Patients aged 70-79 years diagnosed with a pT1-pT2, clinically axillary lymph node-negative, oestrogen and/or progesterone receptor-positive, and human epidermal growth factor receptor 2-negative BrC between 2015 and 2020 were eligible for the study. Factors associated with the omission of the two procedures were evaluated using binary penalised logistic regression models. Axillary staging was omitted in 33/1000 (3.3%) women. After simultaneous adjustment for the centre of treatment and all other key variables, axillary staging was omitted more often in 2015-2016 vs. 2017-2020 (odds ratio (OR): 2.7; 95% CI: 1.0-7.5), in women aged 75-79 vs. 70-74 years (OR: 2.3; 95% CI: 1.1-4.9), and in those who had mastectomy vs. breast-conserving surgery (OR: 3.3; 95% CI: 1.2-9.0). The higher the histological grade was, the less frequent were the omissions (OR for grade 3 vs. grade 1: 0.2; 95% CI: 0.0-0.7). Post-lumpectomy radiotherapy was omitted in 56/651 (8.6%) women with no significant association with age, period, tumour stage, and tumour grade. In conclusion, the omission of axillary staging and post-lumpectomy radiotherapy in low-risk older BrC patients was rare in the Italian IRCCSs. Although women included in the study cannot be considered a nationally representative sample of BrC patients in Italy, our findings can serve as a baseline to monitor the impact of future guidelines. To do that, the recording and storage of hospital-based information should be improved.

The role of rapid on site evaluation on touch imprint cytology and brushing during conventional bronchoscopy

BACKGROUND

The increase in immunohistochemical and molecular predictive tests in lung cancer requires new strategies for managing small samples taken during bronchoscopic procedures. The value of Rapid On Site Evaluation (ROSE) during conventional bronchoscopic procedures on endobronchial neoplasms in optimizing small biopsies and cytologlogical tissue specimens for diagnostic testing, and ancillary studies was evaluated.

METHOD

ROSE on touch imprint cytology (TIC) and brushing was performed on 690 consecutive cases of patients undergoing biopsies, using fiber optic bronchoscopy. Immunohistochemical assay for PD-L1, ALK, and ROS1 and molecular testing, via next generation technique for EGFR, KRAS, and BRAF, were performed.

RESULTS

The concordance between ROSE and final diagnoses was almost perfect for brushing (sensitivity: 0.84; specificity: 0.96), and less so for touch preparations (sensitivity: 0.77; specificity: 0.89). Immunohistochemical assay for PD-L1 was evaluated on 256 bioptic cases with only six unsuitable samples. Material available for immunohistochemistry for ALK was sufficient in 151 biopsies with no inadequate cases. ROS1 was evaluated in 132 biopsies, with only two unsuitable samples. Molecular analysis was performed on 128 biopsies, 29 TIC, and 17 brushing. Out of these, only ten were considered to be unsuitable.

CONCLUSIONS

ROSE is an effective procedure for monitoring the quality and quantity of material taken during conventional bronchoscopic procedures for evaluating the suitability of small samples that must undergo immunohistochemical and molecular assay.

Tumor Infiltrating Lymphocytes and NHERF1 Impact on Prognosis of Breast Cancer Patients

BACKGROUND

Breast cancer (BC) is a heterogeneous disease, and patients with apparently similar clinicopathological characteristics in clinical practice show different outcome. This study evaluated in primary BCs and in the subgroup of the triple-negative breast cancers (TNBCs) the level of tumor infiltrating lymphocytes (TILs), Na⁺/H⁺ exchanger regulatory factor 1 (NHERF1) expression, and their association respect to the clinical outcome of patients.

MATERIAL AND METHODS

NHERF1 expression was assessed by immunohistochemistry in 338 BC samples; the analysis of TILs was examined using hematoxylin and eosin stained slides, according to International TILs Working Group 2014.

RESULTS

Multivariate analysis identified TILs as an independent prognostic factor for DFS in the entire cohort and in the TNBC subgroup (HR, 0.32; 95% CI, 0.12-0.87; P = 0.026; and HR, 0.22; 95% CI, 0.06-0.80; P = 0.022, respectively). Univariate and survival analysis by Kaplan-Meier method revealed that patients with cytoplasmic (c) NHERF1^-/TILs⁺ expression had better DFS than other patients (P = 0.049), and this result was also found in the TNBC subgroup (P = 0.031). Moreover, TNBC patients with cNHERF1^-/TILs^- expression had a worse DFS and OS than other patients (P = 0.057 and P = 0.002, respectively).

CONCLUSIONS

In the complex scenario of BC and in the era of tumor immunogenicity and immunotherapy, we found an association of TIL levels and cNHERF1 expression that could be useful to identify BCs and particularly TNBC patients with different prognosis and clinical outcome.

Intratumoral, rather than stromal, CD8+ T cells could be a potential negative prognostic marker in invasive breast cancer patients

BACKGROUND

Tumor infiltrating lymphocytes (TILs) are widely considered a key sign of the immune interaction between host and tumor, and potentially prognostic biomarkers of good or bad outcome in many cancers, included invasive breast cancer (BC). However, results about the association between TIL typology, location and BC prognosis, are controversial. The aim of the study was to evaluated the prognostic significance of TIL subtypes (CD4+, CD8+, FOXP3+ T cells) and their location (stromal "s" and intratumoral "i" CD4+ and CD8+) in BC patients, focusing on the association between these markers and immunocheckpoint molecules such as cytotoxic T lymphocyte antigen 4 (CTLA-4), programmed cell death ligand 1 (PD-L1) and its receptor (PD-1).

METHODS

CD4+, CD8+, FOXP3+, CTLA4+, PD-L1+ and PD-1+ expression was examined by immunohistochemistry on tissue microarrays (TMAs) from 180 BC patients. Univariate and Kaplan-Meier analyses of disease free survival (DFS) were performed to evaluate the prognostic significance of marker expression.

RESULTS

Total CD8+ T cells were not significantly associated with DFS. Differently, patients with iCD8+ and sCD8+ overexpression showed a trend toward respectively a worse (P = .050) and a better 5-years DFS (P = .064). Interestingly, TIL expression of both PD-1+ and PD-L1+, was significantly associated with iCD8+ (P = .0004; P < .0001 respectively), while only TIL expression of PD-1 was associated with sCD8+ (P = .001).

CONCLUSION

Our data show that iCD8+ T cells, but no sCD8+ T cells identify a subgroup of patients with poor DFS and this could be due to the overexpression of PD-L1/PD-1 pathway.

Discordance between FISH, IHC, and NGS Analysis of ALK Status in Advanced Non-Small Cell Lung Cancer (NSCLC): a Brief Report of 7 Cases

BACKGROUND: Anaplastic lymphoma kinase (ALK) rearrangement represents a landmark in the targeted therapy of non–small cell lung cancer (NSCLC). Immunohistochemistry (IHC) is a sensitive and specific method to detect ALK protein expression, possibly an alternative to fluorescence in situ hybridization (FISH). In this study, the concordance of FISH and IHC to determine ALK status was evaluated, particularly focusing on discordant cases. MATERIALS AND METHODS: ALK status was tested by FISH and the IHC validated method (Ventana ALK (D5F3) CDx Assay) in 95 NSCLCs. Discordant cases were analyzed also by next-generation sequencing (NGS). The response to crizotinib of treated patients was recorded. RESULTS: Seven (7.3%) discordant cases were ALK FISH positive and IHC negative. They showed coexistent split signals pattern, with mean percentage of 15.4%, and 5′ deletions pattern, with mean percentage 31.7%. Two cases had also gene amplification pattern. In three cases (42.8 %), the polysomy was observed. The NGS assay confirmed IHC results. In these patients, the treatment with crizotinib was ineffective. CONCLUSIONS: In our discordant cases, a coexistent complex pattern (deleted, split, and amplified/polysomic) of ALK gene was observed by FISH analysis. These complex rearranged cases were not detectable by IHC, and it could be speculated that more complex biological mechanisms could modulate protein expression. These data highlight the role of IHC and underscore the complexity of the genetic pattern of ALK. It could be crucial to consider these findings in order to best select patients for anti-ALK treatment in daily clinical practice.

Thyroglobulin Determination in Fine Needle Aspiration Biopsy Washout of Suspicious Lymph Nodes in Thyroid Carcinoma Follow up

BACKGROUND

Differentiated thyroid carcinomas (DTCs) account for about 1% of all human malignancies. Cervical lymph nodes metastases and recurrences in the thyroid bed frequently occur. Furthermore, about 10-15% of patients develop distant metastases. Therefore, patients must undergo life-long follow-up.

OBJECTIVE

The aim of this study was to evaluate the usefulness of Thyroglobulin measurement in FNAB washout (FNAB-Tg) in the detection of local metastasis in patients affected by or evaluated for thyroid cancer.

MATERIALS AND METHODS

In a 3-year period, a total of 83 consecutive patients coming to our attention at the Ear-Nose-Throat (ENT) Outpatients Service of the National Cancer Research Center &amp;quot;Istituto Tumori Giovanni Paolo II&amp;quot; of Bari, Italy, because of the finding of one or more cervical lymph node(s), were enrolled in the study. After collection of the cytological specimen, the needle used for performing FNAB was then washed in 1 ml of normal saline. 89 FNAB washouts were collected from the same number of lymph nodes and subsequently investigated for Thyroglobulin levels using a sequential chemiluminescent-immunometric assay.

RESULTS

Comparing the cytological or, when performed, histological diagnoses with the results of FNAB-Tg, we found that in 24 cases of lymph node metastases from PTC (19 lymph nodes from patients at the first diagnoses and 5 lymph nodes from PTC patients in follow up) the mean level of Thyroglobulin was 1840.11 ng/ml; range: <0,2 to 11440 ng/ml. In the group of PTC patients (27 lymph nodes) with lymph nodes negative for metastatic involvement at cytology (i.e. no lymph node recurrence at follow-up), as well as in the cases of subjects without PTC and submitted to FNAB because of the appearance of lymph node(s) classified as reactive at cytology (37 lymph nodes), FNAB-Tg was lower than or equal to 0.2 ng/ml. As expected, the Thyroglobulin level was not detectable (< 0.2 ng/ml) also in a lymph node FNAB from a case of anaplastic thyroid carcinoma.

CONCLUSION

In our study, FNAB-Tg was not detectable in all node negative patients showing, when considering together all the lymph node metastases, a 96% sensitivity and 100% specificity.

β-catenin interaction with NHERF1 and RASSF1A methylation in metastatic colorectal cancer patients

There is an increasing need to identify new biomarkers in colorectal cancer (CRC) to further characterize this malignancy. β-catenin plays a central role in the Wnt signaling pathway. It also binds Na⁺/H⁺ exchanger regulating factor 1 (NHERF1) and interacts with the RAS-association domain family 1, isoform A (RASSF1A), but the mechanisms of this possible crosstalk are still not fully understood. In this study, we analyzed for the first time the different subcellular expression of β-catenin, NHERF1, and RASSF1A and their relationships with RASSF1A methylation in the progression of CRC. We assessed immunohistochemical expression and RASSF1A methylation in 51 patients with stage IV colorectal cancer. Biomarker expression analysis was carried out considering the tumor-adjacent normal tissue, the primary tumor, and the paired liver metastases. Regarding the tumor compartment, it was found that cytoplasmic β-catenin expression was positively correlated to membranous (r = 0.3002, p = 0.0323) and nuclear NHERF1 (r = 0.293, p = 0.0368). In the liver metastases, instead, we found a positive correlation of cytoplasmic and nuclear β-catenin expression with RASSF1A methylation (r = 0.4019, p = 0.0068 and r = 0.3194, p = 0.0345, respectively).

In conclusion, our results showed that β-catenin was the crucial protagonist in metastatic CRC through different effector proteins involved in this developing process. In tumor tissues, β-catenin was predominantly associated with NHERF1 in a dynamic context, while interestingly in liver metastases, we noted an increase of its oncogenic function through RASSF1A inactivation.

EGFR Polysomy in Squamous Cell Carcinoma of the Thyroid. Report of Two Cases and Review of the Literature

Aims and background

Primary squamous cell carcinoma of the thyroid gland (PSCCT) is an uncommon malignancy characterized by a poor prognosis. A radical surgical approach combined with radiotherapy or chemotherapy is the generally accepted treatment for this tumor. The epidermal growth factor receptor (EGFR) is a transmembrane tyrosine kinase receptor modulating the cell proliferation and biological progression of many human epithelial tumors. The EGFR overexpression in PSCCT suggests an additional therapeutic option for the treatment of this tumor.

Methods and study design

The clinicopathological features and immunohistochemical profiles of two cases of primary squamous cell carcinoma of the thyroid in a 66-year-old and an 83-year-old woman are presented. EGFR status was valued in both cases.

Results

Overexpression of EGFR protein was detected in 50% and 75% of the tumor cell membranes. EGRF gene polysomy was detected in both tumors.

Conclusions

Pharmaceuticals targeting EGFR may help to provide the rationale for an additional, novel therapeutic option for this rare tumor, especially when other therapeutic options have been exhausted.

NHERF1 together with PARP1 and BRCA1 expression as a new potential biomarker to stratify breast cancer patients

It has been recognized that Na⁺/H⁺ Exchanger Regulatory Factor 1 (NHERF1) in breast cancer (BC) acts as a tumor suppressor or as an oncogenic protein, depending on its subcellular localization. This study aims to correlate NHERF1 expression to BRCA1 and PARP1 proteins, to investigate their relationship, and their biological and clinical significance. Using immunohistochemistry on tissue microarrays, we evaluated subcellular NHERF1, BRCA1 and PARP1 expression in 308 BCs including a subgroup (n=80) of triple negative BCs (TNBCs). Herein, we show that nuclear NHERF1 (nNHERF1) expression was significantly associated with nuclear BRCA1 (nBRCA1) expression (p=0.0008), and an association was also found between nuclear PARP1 (nPARP1) and nBRCA1 (p<0.0001). Cytoplasmic NHERF1 (cNHERF1) was correlated to nPARP1 (p<0.0001). Survival analyses showed that the patients with positive nPARP1 and nNHERF1 tended toward a shorter 5-year overall survival (OS) (p=0.057). In TNBCs, the association between nBRCA1 and nPARP1 was maintained (p<0.0001), and an association between nNHERF1 and nPARP1 was observed (p=0.010). Univariate analysis revealed that TNBCs with positive cNHERF1 and nPARP1 had a shorter 5-year OS (p=0.048).

Our data suggest that NHERF1 could be a new potential biomarker in combination with PARP1 and BRCA1 expression to stratify BC patients. In particular, in TNBCs, cNHERF1 associated with nPARP1 expression identified a patient subgroup with a shorter survival, for whom it may be useful to develop novel therapeutic strategies.

VEGF and TWIST1 in a 16-biomarker immunoprofile useful for prognosis of breast cancer patients

This study concerns the expression of biomarkers involved in diverse pathways, such as progression, DNA repair mechanisms and angiogenesis to establish an immunoprofile capable of characterizing sporadic versus familial breast cancers (BCs). The aim was to identify a patient subgroup with a different clinical outcome, which could then be directed towards new targeted therapies. Hierarchical cluster analysis (HCA) was carried out using the immunohistochemical score from tissue microarray sections of an initial cohort of 183 (88 sporadic and 95 familial) patients with invasive BC. For the survival analysis, only those patients with complete follow-up were considered. The HCA revealed a 16-protein immunoprofile, nine of which represent the core, as was also found when familial and sporadic BCs were analysed individually. The 16-biomarker immunoprofile was able to identify a group of patients (Group 1) with a more aggressive tumour phenotype. Survival analyses showed that VEGF⁺ /TWIST1^- patients with familial BC of Group 1 tended to demonstrate a lower DFS than the VEGF^- /TWIST1⁺ sporadic BC patients of Group 2 (p = 0.052). Moreover, the entire cohort of VEGF⁺ /TWIST1^- patients showed a statistically worse DFS than the patients with VEGF^- /TWIST1⁺ expression (p = 0.034). In conclusion, we found that tumour stratification based on an immunoprofile is useful to predict the patient clinical behaviour. In particular, our study indicates that the clustering of tumors on the basis of this immunoprofile suggests the possibility to differentiate familial from sporadic BCs and to clinically select those patients who are more likely to benefit from inhibition of the VEGF pathway.

Is immunohistochemistry of BRAF V600E useful as a screening tool and during progression disease of melanoma patients?

BACKGROUND

In clinical practice the gold standard method to assess BRAF status in patients with metastatic melanoma is based on molecular assays. Recently, a mutation-specific monoclonal antibody (VE1), which detects the BRAF V600E mutated protein, has been developed. With this study we aimed to confirm the clinical value of the VE1 Ventana® antibody, as today a univocal validated and accredited immunohistochemical procedure does not exist, to preliminary detect BRAF status in our routine diagnostic procedures. Moreover, we explored the biological meaning of BRAF immunohistochemical labeling both as a predictor marker of response to target therapy and, for the first time, as a player of acquired tumor drug resistance.

METHODS

We analyzed a retrospective series of 64 metastatic melanoma samples, previously investigated for molecular BRAF status, using a fully automatized immunohistochemical method. We correlated the data to the clinicopathologic characteristics of patients and their clinical outcome.

RESULTS

The sensitivity and the specificity of the Ventana® VE1 antibody were 89.2 and 96.2% respectively, while the positive predictive value and negative predictive value were 97.1 and 86.2%, respectively. For six mutated patients the histological sample before treatment and when disease progressed was available. The immunohistochemical BRAF V600E expression in the specimens when disease progressed was less intense and more heterogeneous compared to the basal expression. Multivariate analysis revealed that a less intense grade of positive expression is an independent predictor of a less aggressive stage at diagnosis (p = 0.0413).

CONCLUSIONS

Our findings encourage the introduction of immunohistochemistry as a rapid screening tool for the assessment of BRAF status in melanoma patients in routine diagnostic procedures and prepare the ground for other studies to highlight the role of immunohistochemical BRAF V600E expression in patients at the time of progression.

Immunoprofile from tissue microarrays to stratify familial breast cancer patients

Familial breast cancer (BC) is a heterogeneous disease with variable prognosis. The identification of an immunoprofile is important to predict tumor behavior for the routine clinical management of familial BC patients. Using immunohistochemistry on tissue microarrays, we studied 95 familial BCs in order to analyze the expression of some biomarkers involved in different pathways. We used unsupervised hierarchical clustering analyses (HCA), performed using the immunohistochemical score data, to define an immunoprofile able to characterize these tumors. The analyses on 95 and then on a subset of 45 tumors with all biomarkers contemporarily evaluable, revealed the same biomarker and patient clusters. Focusing on the 45 tumors we identified a group of patients characterized by the low expression of estrogen receptor (P = 0.009), progesterone receptor (P < 0.001), BRCA1 (P = 0.005), nuclear Na⁺/H⁺ exchanger regulatory factor 1 (NHERF1) (P = 0.026) and hypoxia inducible factor-1 alpha (P < 0.001), and also by the higher expression of MIB1 (P = 0.043), cytoplasmic NHERF1 (P = 0.004), cytoplasmic BRCT-repeat inhibitor of hTERT expression (P = 0.001), vascular endothelial growth factor (VEGF) (P = 0.024) and VEGF receptor-1 (P = 0.029). This immunoprofile identified a more aggressive tumor phenotype associated also with a larger tumor size (P = 0.012) and G3 grade (P = 0.006), confirmed by univariate and multivariate analyses. In conclusion, the clinical application of HCA of immunohistochemical data could allow the assessment of prognostic biomarkers to be used simultaneously. The 10 protein expression panel might be used to identify the more aggressive tumor phenotype in familial BC and to direct patients towards a different clinical therapy.

Activating c-KIT mutations in a subset of thymic carcinoma and response to different c-KIT inhibitors

BACKGROUND

To analyze a multi-institutional series of type C thymic carcinomas (TCs) (including neuroendocrine tumors), focusing on the expression and mutations of c-KIT.

MATERIALS AND METHODS

Immunohistochemical expression of c-KIT/CD117, p63, CD5 and neuroendocrine markers, as well as mutational analysis of c-KIT exons 9, 11, 13, 14, 17 by direct sequencing of 48 cases of TCs. Immunohistochemical and molecular data were statistically crossed with clinicopathological features.

RESULTS

Overall, 29 tumors (60%) expressed CD117, 69% were positive for CD5 and 85% (41 cases) for p63. Neuroendocrine markers stained all six atypical carcinoids and five poorly-differentiated thymic squamous cell carcinomas. Overall, six CD117-positive cases (12.5%) showed c-KIT mutation. No mutation was detected in CD117-negative tumors and carcinoids. All the mutations were found in poorly-differentiated thymic squamous cell carcinomas expressing CD117, CD5, p63 and lacking neuroendocrine markers (6 of 12 cases with these features). Mutations involved exon 11 (four cases: V559A, L576P, Y553N, W557R), exon 9 (E490K) and exon 17 (D820E).

CONCLUSIONS

All TCs need an immunohistochemical screening with CD117, while c-KIT mutation analysis is mandatory only in CD117-positive cases, particularly when coexpressing CD5 and p63, lacking neuroendocrine differentiation. The finding of c-KIT mutation can predict efficacy with different c-KIT inhibitors.

Giant genital cavernous haemangioma: case description and surgical management

Giant genital haemangiomas are rare occurrences. Once properly diagnosed, they should be managed by surgery with wide and deep margins. We present a clinical case and provide suggestions for diagnosis and treatment of this unusual pathology.

Rapidly-growing hemangioma of the testicle clinically simulating an aggressive neoplasm. A case report

We present a case of intraparenchymatous capillary-type hemangioma of the testicle in an adult. The patient was a 37-year-old man who showed a rapidly enlarging and palpable mass in left testicle. Radical orchiectomy was performed, and histological examination revealed an unencapsulated lobulated tumour with wide hemorrhagic portions. To our knowledge, the occurrence of rapid enlargement in a testicular hemangioma has not been previously reported, which might be explained by the development of intra-tumoural haemorrhage.

Expression of estrogen receptor in hemangioma of the uterine cervix: reports of three cases and review of the literature

The occurrence of hemangioma in the female genital tract, particularly in uterine cervix, is rare. The majority of them show asymptomatic behavior. Surgical excision remains curative in most of the cases. Conservative therapies such as sclerosing agents, cryotherapy, and CO(2) laser excision may be alternatively applied. We present three cases of hemangiomas of the cervix in asymptomatic women, diagnosed as cavernous hemangioma in two cases and capillary hemangioma in one. All tumors were immunoreactive for CD31, CD34, factor-VIII-related antigen. Focal expression of estrogen receptors was detected. No positivity was obtained with progesterone receptor antibodies. The presence of estrogen receptor in the endothelial cells of the hemangioma of the cervix suggests a direct role of this hormone in the hemangioma development. A possible target therapy is discussed.

Microsatellite and EGFR, HER2 and K-RAS analyses in sclerosing hemangioma of the lung

Sclerosing hemangioma (SH) is an uncommon pulmonary tumor thought to derive from primitive respiratory epithelium consisting of 2 cell populations (cuboidal surface and polygonal stromal cells) and sharing some clinical characteristics (frequent occurrence in nonsmoking women of Asian ethnicity) with bronchioloalveolar carcinoma with which it has been suggested a possible common origin. We investigated 11 cases of SH by immunohistochemistry, fluorescence in situ hybridization, and polymerase chain reaction-based microsatellite and mutational analyses with particular emphasis on possible alterations of microsatellite loci located at tumor suppressor genes (FHIT, p16, Rb, and p53) involved in lung adenocarcinoma genesis and EGFR, HER2, and K-RAS genes. Although EGFR expression was observed in all tested cases, none showed HER2 immunostaining. Fluorescence in situ hybridization and mutational analysis of EGFR and HER2 and also K-RAS sequencing did not reveal molecular alterations, whereas allelic losses at p16 and Rb loci (4 and 2 out of 9 tested cases, respectively) with an identical microsatellite allelic loss pattern in both cuboidal and polygonal cells were observed. The finding of microsatellite alterations in chromosomal regions related to genes deeply involved in early stage lung adenocarcinoma could suggest a possible link between SH and bronchioloalveolar carcinoma, but tumor pathway promoted by EGFR, HER2, and K-RAS does not represent a common molecular mechanism of tumorigenesis. Microsatellite alterations identified in cuboidal and polygonal cells further confirm the clonal and neoplastic nature of both components of SH.

Pleural malignant solitary fibrous tumor with sarcomatous overgrowth showing PDGFRbeta mutation

Pleural malignant solitary fibrous tumors (SFTs) are uncommon, and little is known about their histogenesis and molecular features. We report a case of pleural SFT with sarcomatous overgrowth that showed expression for PDGFRbeta and a missense mutation on exon 18 of the PDGFRbeta gene. The involvement of the PDGFRbeta gene in SFT is compatible with a pericytic derivation, also supporting a possible role of this tyrosine kinase in malignant transformation and in the adoption of novel molecular therapies.

Role of chemotherapy and the receptor tyrosine kinases KIT, PDGFRalpha, PDGFRbeta, and Met in large-cell neuroendocrine carcinoma of the lung

PURPOSE

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a relatively uncommon, high-grade neuroendocrine tumor sharing several features with small-cell lung carcinoma (SCLC) but currently considered as a variant of non-SCLC and accordingly treated with poor results. Little is known about the optimal therapy of LCNEC and the possible therapeutic molecular targets.

PATIENTS AND METHODS

We reviewed 83 patients with pure pulmonary LCNEC to investigate their clinicopathologic features, therapeutic strategy, and immunohistochemical expression and the mutational status of the receptor tyrosine kinases (RTKs) KIT, PDGFRalpha, PDGFRbeta, and Met.

RESULTS

LCNEC histology predicted a dismal outcome (overall median survival, 17 months) even in stage I patients (5-year survival rate, 33%). LCNEC strongly expressed RTKs (KIT in 62.7% of patients, PDGFRalpha in 60.2%, PDGFRbeta in 81.9%, and Met in 47%), but no mutations were detected in the exons encoding for the relevant juxtamembrane domains. Tumor stage and size (> or = 3 cm) and Met expression were significantly correlated with survival. At univariate and multivariate analysis, SCLC-based chemotherapy (platinum-etoposide) was the most important variable correlating with survival, both in the adjuvant and metastatic settings (P < .0001).

CONCLUSION

Pulmonary LCNEC represents an aggressive tumor requiring multimodal treatment even for resectable stage I disease, and LCNEC seems to respond to adjuvant platinum-etoposide-based chemotherapy. Patients who received this therapy had the best survival rate. Despite our failure in finding mutational events in the tested RTKs, the strong expression of KIT, PDGFRalpha, PDGFRbeta, and Met in tumor cells suggests an important role of these RTKs in LCNEC, and these RTKs seem to be attractive therapeutic targets.

The value of c-kit mutational analysis in a cytokeratin positive gastrointestinal stromal tumour

The expression of cytokeratins in gastrointestinal stromal tumours (GISTs) is rare and may lead to diagnostic confusion when it occurs. This report describes a metastatic GIST that stained strongly for cytokeratins, CD117, and CD34 in a patient who was previously diagnosed with gastric epithelioid angiosarcoma. A review of both tumours showed the same histological and immunohistochemical profiles, and c-kit molecular analysis revealed an insertional mutation at codon 558 of exon 11 in both tumours. Thus, pathologists should be aware that GISTs can occasionally express cytokeratins, and that c-kit mutational investigations may have a key diagnostic role and may prevent diagnostic mistakes that could have important clinical implications.