Novel microRNA-based assay demonstrates 92% agreement with diagnosis based on clinicopathologic and management data in a cohort of patients with carcinoma of unknown primary.

BACKGROUND: Cancer of unknown or uncertain primary is a major diagnostic and clinical challenge, since identifying the tissue-of-origin of metastases is crucial for selecting optimal treatment. MicroRNAs are a family of non-coding, regulatory RNA molecules that are tissue-specific, with a great potential to be excellent biomarkers. METHODS: In this study we tested the performance of a microRNA-based assay in formalin-fixed paraffin-embedded samples from 84 CUP patients. RESULTS: The microRNA based assay agreed with the clinical diagnosis at presentation in 70% of patients; it agreed with the clinical diagnosis obtained after patient management, taking into account response and outcome data, in 89% of patients; it agreed with the final clinical diagnosis reached with supplemental immunohistochemical stains in 92% of patients, indicating a 22% improvement in agreement from diagnosis at presentation to the final clinical diagnosis. In 18 patients the assay disagreed with the presentation diagnosis and was in agreement with the final clinical diagnosis, which may have resulted in the administration of more effective chemotherapy. In three out of four discordant cases in which supplemental IHC was performed, the IHC results validated the assay's molecular diagnosis. CONCLUSIONS: This novel microRNA-based assay shows high accuracy in identifying the final clinical diagnosis in a real life CUP patient cohort and could be a useful tool to facilitate administration of optimal therapy.

Immunohistochemical study of the epithelial-mesenchymal transition phenotype in cancer of unknown primary: incidence, correlations and prognostic utility.

BACKGROUND: The epithelial to mesenchymal transition (EMT) has been associated with metastatic dissemination and poor outcome in several solid tumour types. Our aim was to study its incidence and its prognostic significance in cancer of unknown primary (CUP). PATIENTS AND METHODS: One hundred tumour samples of CUP were loaded in tissue microarrays and were studied for immunohistochemical (IHC) expression of E-cadherin, N-cadherin, vimentin, the EMT transcription factor (SNAIL) and the stem cell marker octamer-binding transcription marker 4(OCT4). An EMT phenotype was defined as low expression of E-cadherin, expression of N-cadherin with/without vimentin with concomitant expression of SNAIL, as assessed by percentage of tumour cell staining. RESULTS: Among 100 CUP cases, the histological diagnosis was adenocarcinoma in 55, squamous carcinoma in 20 and undifferentiated carcinoma in 15, with a high grade seen in 46. Therapy consisted of palliative chemotherapy, mostly platinum based. The median progression-free survival and overall survival (OS) were 7 and 12 months respectively. Distributional studies resulted in selection of IHC cut-offs for E-cadherin (negative when expressed in <60% of tumour cells), N-cadherin, vimentin (positive when expressed in ≥40% of tumour cells), SNAIL (positive when stained in ≥80% of tumour cells). An EMT phenotype was observed in 8 cases (8.1%) and was strongly associated with poor OS (median OS EMT(-)=13 months vs. median OS EMT(+)=8 months, p=0.023). When we used staining intensity (H-Score), an EMT phenotype was observed in 16 patients and carried borderline adverse prognostic utility for outcome (median OS 9 vs. 14 months, p=0.07). The presence of the EMT phenotype correlated significantly with male gender, high grade and presence of visceral metastases (χ(2) p<0.05), while EMT mediator expression was correlated to high NOTCH 2/3 expression. Other factors, prognostic for poor survival, were male gender, PS≥2, non-platinum therapy (χ(2) p<0.05). CONCLUSION: EMT is infrequently seen in tumours of CUP. However, an adverse prognostic significance for patient outcome has been identified and may warrant studies of therapeutic targeting.

Profiling immunohistochemical expression of NOTCH1-3, JAGGED1, cMET, and phospho-MAPK in 100 carcinomas of unknown primary.

Cancer of unknown primary (CUP) is a heterogeneous entity, managed on the basis of "one size fits all" therapeutic concepts; insights into the molecular biology of CUP are urgently needed. We retrospectively examined the immunohistochemical (IHC) expression of Notch1, 2, 3, Jagged1, cMET, and pMAPK biomolecules in 100 CUP tumors using tissue microarrays, aiming to study their correlation to clinicopathologic characteristics and prognostic utility for patient outcome. Notch3 and pMAPK were most frequently expressed (97 and 91 %, respectively). A linear correlation of Notch3 and cMET expression was found (p = 0.001), while pMAPK emerged as the major adverse prognostic factor (median overall survival OS 9 vs. 17 months, p = 0.016), carrying also a significantly positive predictive value (p = 0.02). Our study indicated a favorable prognostic impact of cMET expression in CUP, both in univariate (median OS 15 vs. 9 months, p = 0.05) and in multivariate analysis (Relative Risk RR for death 0.48, p = 0.025). cMET and Notch3 expression were found to be statistically more frequent in squamous carcinomas (positive in 90 % of cases), associated with a unique metastatic IHC pattern (cMET-high in soft tissue/lymph node metastases, p < 0.001, Notch3-high in visceral, peritoneal/pleural and soft tissue/lymph node metastases, p < 0.001). Our study points to the MAPK and cMET axes as crucial in defining cancer progression and outcome in CUP patients and, if validated, could justify attempts at their therapeutic modulation.

Trabectedin-related rhabdomyolysis: an uncommon but fatal toxicity.

Rhabdomyolysis is defined as the dissolution of striped muscle characterized by the leakage of intracellular muscle components into the circulation, which can ultimately lead to renal failure with a possible fatal outcome. Trabectedin is a potential cause of rhabdomyolysis. Herein, we describe a case of rhabdomyolysis in a female patient with recurrent metastatic leiomyosarcoma of the uterus and who had full recovery, and we review the already published cases in order to identify a common pattern of emergence.

Neuroendocrine carcinoma of unknown primary: a systematic review of the literature and a comparative study with other neuroendocrine tumors.

INTRODUCTION: Neuroendocrine carcinomas of unknown primary (NCUP) represent a specific subset with relatively favorable prognosis. Data on biology, management and outcome of NCUP patients have not been systematically reviewed neither compared to those of neuroendocrine tumors of known primary. PATIENTS AND METHODS: We systematically reviewed all publications studying neuroendocrine CUP patients and presented a single center retrospective patient series. In addition, we analyzed and specified the similarities and/or differences between NCUP and other neuroendocrine malignancies. RESULTS: Five hundred patients with NCUP constituted a heterogeneous cohort in terms of histology, grade, anatomic site and tumor biology in published series and were managed mostly with platinum-based regimens. Among 294 patients with available outcome data, a median survival of 15.5 months (range 11.6-40) was observed. Comparative analysis with neuroendocrine solid tumors (NET) revealed that poorly-differentiated NCUP share an aggressive natural history and a dismal prognosis similar to high grade pulmonary and extrapulmonary neuroendocrine carcinomas (Large Cell Neuroendocrine bronchial Carcinomas, LCNEC and poorly differentiated gastroenteropancreatic tumors, GEP-NET). Well differentiated NCUP reveal a more indolent course with a survival range resembling that of typical and atypical pulmonary carcinoids, well differentiated gastrointestinal NETs and limited small cell lung carcinomas. CONCLUSION: No evidence for distinct biology or outcome of NCUP patients emerged when histological grade was matched for known primary NETs. The high heterogeneity of the NCUP subgroup limits the potential for identification of reliable prognosticators and hinders development of novel targeted therapies.

Cancer of unknown primary patients with midline nodal distribution: midway between poor and favourable prognosis?

BACKGROUND: Midline nodal cancer of unknown primary (CUP) has varying definitions and an unclear natural history compared to that of extragonadal germ cell cancer (EGCC) and neuroendocrine tumors. METHODS: We systematically reviewed all published series of patients with midline nodal CUP using three distinct definitions and presented our own retrospective cohort. RESULTS: Sixty four fit patients (median age 64) with poorly differentiated carcinoma or adenocarcinoma in midline nodal areas were treated from 1998 to 2008 at our center. Only two patients had elevated serum germ cell markers. Forty-eight percentage of patients responded to platinum-based chemotherapy (CR 11%). The median survival was 12 months (2-year survival 18%). Good PS (Hazard Ratio HR 0.287, p=0.058) and administration of platinum (HR 0.340, p=0.08) predicted for more favourable outcome. A subgroup of 15 male patients selected with stricter criteria had a CR rate of 33% and median survival of 18 months (2-year survival 24%). We identified 10 series of midline nodal CUP patients defined with discordant criteria. Despite high response rates (35-65%) to platinum chemotherapy, the median survival clustered around 12 months. Predictive factors for superior survival were low tumor bulk, patient fitness, female gender, carcinomatous histology, and absence of visceral metastases. There were differences between midline nodal CUP patients and EGCC as well as neuroendocrine tumors (age, tumor markers, response to therapy, long-term survival). CONCLUSIONS: Midline nodal CUP patients are poorly defined, fare less well than EGCC or neuroendocrine cancer and probably constitute a heterogeneous entity with a minority harbouring atypical germ cell cancer.