Cancers of unknown primary site: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

Multi-omic analysis in carcinoma of unknown primary (CUP): therapeutic impact of knowing the unknown

Carcinoma of unknown primary (CUP) is a difficult-to-manage malignancy. Multi-omic profiles and treatment outcome vs. degree of precision matching were assessed. Tumours underwent next-generation sequencing (NGS) [tissue and/or blood-derived cell-free DNA (cfDNA)]. Selected patients had transcriptome-based immune profiling and/or programmed cell death 1 ligand 1 (PD-L1) immunohistochemistry analysis. Patients could be reviewed by a Molecular Tumor Board, but physicians chose the therapy. Of 6497 patients in the precision database, 97 had CUP. The median number of pathogenic tissue genomic alterations was 4 (range, 0-25), and for cfDNA, was 2 (range, 0-9). Each patient had a distinct molecular landscape. Food and Drug Administration (FDA)-approved biomarkers included the following: PD-L1+ ≥ 1%, 30.9% of CUPs tested; microsatellite instability, 3.6%; tumour mutational burden ≥ 10 mutations·Mb-1, 23%; and neurotrophic receptor tyrosine kinase (NTRK) fusions, 0%. RNA-based immunograms showed theoretically druggable targets: lymphocyte activation gene 3 protein (LAG-3), macrophage colony-stimulating factor 1 receptor (CSF1R), adenosine receptor A2 (ADORA2) and indoleamine 2,3-dioxygenase 1 (IDO1). Overall, 56% of patients had ≥ 1 actionable biomarker (OncoKB database). To quantify the degree of matching (tumours to drugs), a Matching Score (MS; roughly equivalent to number of alterations targeted/total number of deleterious alterations) was calculated post hoc. Comparing evaluable treated patients [MS high, > 50% (N = 15) vs. low ≤ 50% (N = 47)], median progression-free survival was 10.4 vs. 2.8 months (95% CI 0.11-0.64; HR 0.27; P = 0.002); survival, 15.8 vs. 6.9 months (95% CI 0.17-1.16; HR 0.45; P = 0.09); and clinical benefit rate (stable disease ≥ 6 months/partial/complete response), 71% vs. 24% (P = 0.003). Higher MS was the only factor that predicted improvement in outcome variables after multivariate analysis. In conclusion, CUPs are molecularly complex. Treatments with high degrees of matching to molecular alterations (generally achieved by individualized combinations) correlated with improved outcomes.

Efficacy of pembrolizumab in patients with advanced cancer of unknown primary (CUP): a phase 2 non-randomized clinical trial

BACKGROUND

Cancer of unknown primary (CUP) is an aggressive rare malignancy with limited treatment options. Data regarding clinical activity of immune checkpoint inhibitors in CUP is lacking. Therefore, we evaluated the efficacy of pembrolizumab, a programmed cell death-1 inhibitor, in patients with CUP.

METHODS

The study was designed as a phase 2 basket trial for independent rare tumor cohorts including CUP. Adult patients with CUP who had progressed on previous systemic therapy, performance status 0/1 and measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST V.1.1) were eligible. Patients received pembrolizumab (200 mg) intravenously every 21 days. Twenty-nine patients were enrolled and treated between August 2016 and June 2020. The primary endpoint was non-progression rate (NPR) at 27 weeks (NPR-27) per immune-related RECIST. Key prespecified secondary endpoints were confirmed objective response rate (ORR), safety, duration of response (DoR), progression-free survival (PFS) and overall survival (OS). Pretreatment biopsies were examined for biomarkers of response (programmed cell death ligand-1 (PD-L1) expression and tumor infiltrating lymphocytes (TILs)).

RESULTS

Among 25 (of 29 enrolled) eligible and evaluable patients, 14 (56%) had poorly differentiated carcinoma. Patients received a median of two lines of therapy prior to enrollment. Median follow-up was 27.3 months. NPR-27 was observed in seven patients (28.0% (95% CI: 12.1 to 49.4)). ORR was 20.0% (95% CI: 6.8 to 40.7) with five patients achieving immune-related partial response with median DoR of 14.7 months (95% CI: 9.8 to 19.6). Median PFS and OS were 4.1 (95% CI: 3.1 to 5.1) and 11.3 (95% CI: 5.5 to 17.1) months, respectively. Treatment-related adverse events of any and grade ≥3 were seen in 19 (76%) and 4 (16%) patients, respectively. One (4%) patient had grade 3 immune-related acute kidney injury requiring treatment discontinuation. Neither PD-L1 nor TILs were associated with NPR-27. Both positive PD-L1 staining (44.4% vs 6.3%; p=0.040) and intense TIL infiltration (44.4% vs 6.3%; p=0.040) were associated with response.

CONCLUSION

Pembrolizumab showed encouraging efficacy in patients with CUP with acceptable safety profile.

TRIAL REGISTRATION NUMBER

NCT02721732.

Therapeutic Actionability of Circulating Cell-Free DNA Alterations in Carcinoma of Unknown Primary

Cancer of unknown primary (CUP) is a metastatic disease with unidentifiable primary tumor. Somatic alterations can be assessed noninvasively via liquid biopsies interrogating cell-free DNA (cfDNA).

METHODS

We evaluated 1,931 patients with CUP with a cfDNA next-generation sequencing panel (73-74 genes).

RESULTS

Overall, 1,739 patients (90%) had ≥ 1 cfDNA alteration. We then explored alteration actionability (per the levels of evidence from the OncoKB database); 825 patients (47.4% of 1,739) had level 1, level 2, or resistance/R1 alterations. Among 40 clinically annotated patients with CUP who had cfDNA evaluated, higher degrees of matching treatment to alterations (Matching Score > 50% v ≤ 50%) was the only variable predicting improved outcome: longer median progression-free survival (10.4 v 2.5 months; P = .002), overall survival (13.4 v 5.7 months; P = .07, trend), and higher clinical benefit rate (stable disease ≥ 6 months/partial response/complete response; 83% v 25%; P = .003).

CONCLUSION

In summary, cfDNA frequently reveals strong level-of-evidence actionable alterations in CUP, and high degrees of matching to therapy correlates with better outcomes.

Metachronous testicular tumour recurrence in extra-gonadal germ cell tumour: A case report and review of the literature

A 24-year-old male presented in 2014 with left sided abdominal pain and a palpable abdominal mass. After appropriate investigation a diagnosis of an extra-gonadal germ cell tumour was made and he was treated with platinum based chemotherapy. He then underwent retroperitoneal lymph node dissection due to residual disease identified on imaging with no specific tissue type identified on the histological sample. In early 2019 he presented to his General Practitioner with a left sided testicular lump and was diagnosed with non-seminomatous germ cell tumour of the testis, an uncommon condition; metachronous testicular tumour.

Level of Evidence: 5

Cancer of unknown primary - incidence, mortality trend, and mortality-to-incidence ratio is associated with human development index in Central Serbia, 1999-2018: Evidence from the national cancer registry

OBJECTIVES

The aim was to estimate the trend of incidence, mortality and mortality-to-incidence ratio (MIR) in Central Serbia in 1999-2018 and its possible association with the human development index (HDI).

METHODS

In this study, cancer of unknown primary (CUP) was included as C77-C80 codes. Trend analysis was performed in the Joinpoint Regression Programme version 4.8.0.1. HDI combines life expectancy, educational attainment and gross national income. HDI values for Serbia are extracted from the global bank site.

RESULTS

Joinpoint regression analysis of the age-standardised incidence rate of CUP showed a significantly increasing trend with annual percent change (APC) of 8.5% (95% confidence interval [CI] 3.0-14.3%) in males and 7.8% (95%CI 2.7-13.2) in females. The age-standardised mortality rate of CUP showed a significantly decreasing trend with APC of -1.7% (95%CI -2.8 to -0.5%) in males and -1.4% (95%CI -2.7 to -0.1%) in females. MIR showed a significantly decreasing trend with APC of -9.3% (95%CI -14.6 - -3.6%) in males and -7.1% (95%CI -10.5% to -4.2%) in females. The linear regression showed significant inverse association among HDI and the MIR of CUP in males (r²  = 0.464, p = 0.002) and in females (r²  = 0.612, p < 0.001).

CONCLUSIONS

Decline of MIR was associated with HDI, suggesting that CUP prognosis follows socio-economic status.

The usefulness of [18F]FDG-PET/CT in detecting and managing cancers with unknown primary site depends on histological subtype

We assessed the role of [18F]FDG-PET/CT in identifying and managing cancer of unknown primary site (CUP syndrome). We reviewed [18F]FDG-PET/CT scans of individuals with CUP syndrome recorded in clinical referral letters from 2012 to 2019. We evaluated the identification of primary tumor (PT) by [18F]FDG-PET/CT, according to histological subtype, and the impact on clinical management. The median age was 65 years, 36/64 males (56%). PTs were detected in 28/64 (44%) patients. Detection was significantly lower in patients with squamous cell carcinoma (SCC) than with other histologies combined, p = 0.034. Mean age, mean SUVmax (10.6 ± 6.0) and organ involvement were similar between patients with and without discovered PTs; and between patients with SCC and with other histologies combined. However, those with SCC were less likely than the others to present with multi-lesion involvement, p < 0.001. [18F]FDG-PET/CT interpretations apparently affected treatment of 8/28 (29%) patients with PT detected, and in none of the 35 whose PT was not discovered, p < 0.001. [18F]FDG-PET/CT appeared helpful in detecting PT in almost half the patients with CUP syndrome; the lowest rate was for patients with SCC pathology. PET/CT showed limited overall value in guiding clinical management, however benefited those with discovered PT.

Vulvar Paget's Disease Presenting with Fever and Left Inguinal and Peritoneal Lymphadenopathies

BACKGROUND Asymptomatic vulvar Paget's disease is rare and commonly presents with vulvar eczema, erosions, or pruritus. The time from onset to diagnosis of vulvar Paget's disease tends to be rather long because of difficulty making a correct diagnosis owing to similar skin findings with eczema or patients' reluctance to undergo physical examination of their pubic area because of embarrassment. CASE REPORT A 55-year-old woman experienced recurrent episodes of fever for 10 months. Her primary care physician indicated inguinal lymphadenopathy 2 months prior to presentation at our hospital. Contrast-enhanced abdominal computed tomography revealed multiple intra-abdominal lymphadenopathies. With the failure of finding the primary lesion after biopsy, and with a diagnosis of metastatic carcinoma, she was referred to our hospital. On admission, she did not report having vulvar symptoms. As imaging studies revealed no primary lesions, we subsequently added immunostaining to the lymph node biopsy specimens, which suggested Paget's disease. We finally performed a vulvar physical examination and identified eczema. We performed a skin biopsy and histopathological examinations, which provided the final diagnosis of vulvar Paget's disease. CONCLUSIONS We experienced a case of vulvar Paget's disease presenting with inguinal and intraperitoneal lymphadenopathies, without a patient report of vulvar symptoms. When identifying lymphadenopathies, it is crucial to obtain a careful history and perform appropriate physical examinations, suspecting diseases of the vulva or perineum. In addition, immunostaining of lymph node biopsy specimens could be useful in making a correct diagnosis.

A Case Report of Squamous Cell Carcinoma of Unknown Primary That Metastasized to an Inguinal Lymph Node

The term carcinoma of unknown primary (CUP) refers to a malignant tumor whose histology suggests strongly that it is a metastasis, yet the primary lesion is unknown despite sufficient whole body evaluation at the time of examination. CUP has similar incidences in men and women and the average age at diagnosis is 60 years. While its overall incidence varies depending on the report, it generally accounts for 1-5% of all cancers. Thus, it is rare. We encountered a case of squamous cell carcinoma of the inguinal region that seemed to be a metastasis and for which we could not find the primary lesion. This case is reported here along with a literature review on CUP to increase awareness of this rare lesion.

Comprehensive Genomic Profiling of Carcinoma of Unknown Primary Origin: Retrospective Molecular Classification Considering the CUPISCO Study Design

Background

Carcinoma of unknown primary origin (CUP) accounts for 2%–5% of newly diagnosed advanced malignancies, with chemotherapy as the standard of care. CUPISCO (NCT03498521) is an ongoing randomized trial using comprehensive genomic profiling (CGP) to assign patients with CUP to targeted or immunotherapy treatment arms based on genomic profiling. We performed a retrospective analysis of CUP cases referred for CGP to determine how many were potentially eligible for enrollment into an experimental CUPISCO arm.

Materials and Methods

Centrally reviewed adenocarcinoma and undifferentiated CUP specimens in the FoundationCore database were analyzed using the hybrid capture‐based FoundationOne CDx assay (mean coverage, >600×). Presence of genomic alterations, microsatellite instability (MSI), tumor mutational burden (TMB), genomic loss of heterozygosity (gLOH), and programmed death‐ligand 1 (PD‐L1) positivity were determined.

Results

A total of 96 of 303 patients (31.7%) could be matched to an experimental CUPISCO arm. Key genomic alterations included ERBB2 (7.3%), PIK3CA (6.3%), NF1 (5.6%), NF2 (4.6%), BRAF (4.3%), IDH1 (3.3%), PTEN, FGFR2, EGFR (3.6% each), MET (4.3%), CDK6 (3.0%), FBXW7, CDK4 (2.3% each), IDH2, RET, ROS1, NTRK (1.0% each), and ALK (0.7%). Median TMB was 3.75 mutations per megabase of DNA; 34 patients (11.6%) had a TMB ≥16 mutations per megabase. Three patients (1%) had high MSI, and 42 (14%) displayed high PD‐L1 expression (tumor proportion score ≥50%). gLOH could be assessed in 199 of 303 specimens; 19.6% had a score of >16%.

Conclusions

Thirty‐two percent of patients would have been eligible for targeted therapy in CUPISCO. Future studies, including additional biomarkers such as PD‐L1 positivity and gLOH, may identify a greater proportion potentially benefiting from CGP‐informed treatment. Clinical trial identification number. NCT03498521

Implications for Practice

The findings of this retrospective analysis of carcinoma of unknown primary origin (CUP) cases validate the experimental treatment arms being used in the CUPISCO study (NCT03498521), an ongoing randomized trial using comprehensive genomic profiling to assign patients with CUP to targeted or immunotherapy treatment arms based on the presence of pathogenic genomic alterations. The findings also suggest that future studies including additional biomarkers and treatment arms, such as programmed death‐ligand 1 positivity and genomic loss of heterozygosity, may identify a greater proportion of patients with CUP potentially benefiting from comprehensive genomic profiling‐informed treatment.

This article focuses on the ability of comprehensive genomic profiling to identify potentially targetable genetic alterations in cancers of unknown primary, based on the inclusion criteria for the CUPISCO clinical trial and aiming for more effective therapeutic options for patients.

Cancer of unknown primary inside the gastric wall identified by endoscopic submucosal dissection

We report the rare and interesting case of cancer of unknown primary (CUP) detected by endoscopic submucosal dissection (ESD). A 67-year-old man with a gastric adenoma was referred to our hospital for endoscopic treatment. Esophagogastroduodenoscopy revealed a 15-mm submucosal tumor (SMT) at the lesser curvature of the lower gastric body, near the gastric adenoma. Both lesions were resected by ESD. Pathological examination showed that the SMT was a poorly differentiated adenocarcinoma with lymphatic tissue. Additional surgical resection was performed, and the lymph nodes were found to have the same pathological findings as the SMT. These lesions were diagnosed as CUP because the obvious primary site was not detected with additional examination. The patient has been followed up for 24 months without recurrence.

The Diagnostic Value of Cadherin 17 and CDX2 Expression as Immunohistochemical Markers in Colorectal Adenocarcinoma

BACKGROUND

Colorectal cancer is a major cause of morbidity and mortality throughout the world. Although the diagnosis of colorectal cancer is straightforward in primary site, yet it may represent a diagnostic problem in metastatic tumor of unknown primary origin. Hence, immunohistochemical analysis in combination with morphologic assessment and correlation with clinical data becomes crucial, because it is important to specify the primary site of metastasis since some specific tumor types may respond well to targeted molecular therapies. Therefore, establishment of reliable diagnostic markers that confirm or rule out colorectal origin is mandatory.

AIM

To study the expression of cadherin 17 and CDX2 in colorectal carcinoma and to evaluate their diagnostic roles in identifying metastatic colonic from non-colonic adenocarcinomas in cancer of unknown primary site.

DESIGN AND METHODS

This retrospective study included 65 cases of adenocarcinomas: 35 cases of colorectal adenocarcinoma (primary or metastatic) and 30 cases of non-colorectal adenocarcinoma. They were retrieved from the archives of Pathology Department of Ain Shams University and Ain Shams University Specialized Hospitals during the period from 2010 to 2015. Immunohistochemical study was performed using cadherin 17 and CDX2 antibodies.

RESULTS

The sensitivity and specificity of CDX2 and cadherin 17 are 97.1% and 53.3% and 100% and 50% in detecting colonic adenocarcinoma respectively. The PPV, NPV, and overall accuracy of CDX2 versus cadherin 17 were 70.8%, 94.1%, and 76.9% versus 70%, 100%, and 76.9% respectively.

CONCLUSION

Cadherin 17 is a more sensitive marker than CDX2 in diagnosis of carcinoma of unknown primary site especially when colorectal carcinoma is suspected.

Detection efficiency of 18F-flourodeoxyglucose positron emission tomography/computed tomography for primary tumors in patients with carcinoma of unknown primary

Carcinoma of unknown primary (CUP) is defined as biopsy proven tumor metastases that remains unidentified after a thorough diagnostic evaluation. The purpose of this study was to find the detection efficiency of ¹⁸F-flourodeoxyglucose positron emission tomography/computed tomography (¹⁸FDG PET/CT) in patients with CUP. This prospective study was conducted at PET/CT Section of Department of Radiology, Aga Khan University Hospital Karachi, Pakistan from August 2017 to January 2018. Patients with a history of CUP referred for ¹⁸FDG PET/CT scan for detection of primary sites during the study were recruited. ¹⁸FDG PET/CT scan was acquired using standardized protocol, and patients with suspected primary sites underwent biopsies. Scan findings and biopsy results were analyzed to find the detection rate, sensitivity, area under curve (AUC), and positive predictive value (PPV). As no biopsy was performed in negative scan, true negative, and specificity could not be calculated. During the study, 46 consecutive patients with CUP were included. Mean age of cohort was 58 ± 17 years (63% male and 37% female) having a mean body mass index of 24.70 ± 4.97 kg/m². Thirty-four patients (34/46) found to have a hypermetabolic focus suggestive of the primary tumor with known metastatic sites and subjected to biopsy which turned out to be positive in 26/34 patients (true positive). The primary tumor was detected in gastrointestinal and hepatobiliary in 8 (17%), head and neck in 6 (13%), genitourinary 4 (09%), lung 3 (06%), and miscellaneous sites in 5 (11%) patients. Detection rate, sensitivity and PPV of ¹⁸FDG PET/CT were 57%, 68%, and 76%, respectively. Remaining 12/46 patients with negative ¹⁸FDG PET/CT for primary focus did not have biopsy. Receiver operating character curve revealed fair diagnostic strength of ¹⁸FDG PET/CT for detecting unknown primary (AUC 0.667; P = 0.054; standard error = 0.083; confidence interval: 0.504–0.830). We conclude that ¹⁸FDG PET/CT is an effective tool for detecting primary tumor in patients with CUP and its upfront use could preclude the use of many futile diagnostic procedures. Furthermore, higher resolution scanners and acquiring delayed images in patients with negative study could reduce false-negative results in patients with CUP.

Follicular Dendritic Cell Sarcoma or Not? A Series of 5 Diagnostically Challenging Cases

Imperfect or unusual presentation, morphology, or immunophenotype can make the diagnosis of follicular dendritic cell sarcoma (FDCS) very challenging. To illustrate this, we present 5 unique cases from the archives of our tertiary care academic medical center that presented a diagnostic challenge wherein FDCS was the top differential diagnostic possibility. The workup of these cases, including multiple expert consultations, highlights the importance of avoiding specific pitfalls in the diagnosis of FDCS.

Clinical Implications of Noncoding Indels in the Surfactant-Encoding Genes in Lung Cancer

Lung cancer arises from the accumulation of genetic mutations, usually in exons. A recent study identified indel mutations in the noncoding region of surfactant-encoding genes in lung adenocarcinoma cases. In this study, we recruited 94 patients with 113 lung cancers (88 adenocarcinomas, 16 squamous cell carcinomas, and nine other histologies) who had undergone surgery in our department. A cancer panel was designed in-house for analyzing the noncoding regions, and targeted sequencing was performed. Indels in the noncoding region of surfactant-encoding genes were identified in 29/113 (25.7%) cases and represent the precise cell of origin for the lung cancer, irrespective of histological type and/or disease stage. In clinical practice, these indels may be used as clonal markers in patients with multiple cancers and to determine the origin of cancer of unknown primary site.

[2018 Consensus statement by the Spanish Society of Pathology and the Spanish Society of Medical Oncology on the diagnosis and treatment of cancer of unknown primary]

Cancer of unknown primary is defined as a heterogeneous group of tumours that present with metastasis, and in which attempts to identify the original site have failed. They differ from other primary tumours in their biological features and how they spread, which means they can be considered a separate entity. There are several hypotheses regarding their origin, but the most plausible explanation for their aggressiveness and chemoresistance seems to involve chromosomal instability. Depending on the type of study done, cancer of unknown primary can account for 2-9% of all cancer patients, mostly 60-75 years old. This article reviews the main clinical, pathological and molecular studies conducted to analyse and determine the origin of cancer of unknown primary. The main strategies for patient management and treatment, by both clinicians and pathologists, are also addressed.

Survival outcome differences based on treatments used and knowledge of the primary tumour site for patients with cancer of unknown and known primary in Ontario

Introduction

Patients with cancer of unknown primary (cup) have pathologically confirmed metastatic tumours with unidentifiable primary tumours. Currently, very little is known about the relationship between the treatment of patients with cup and their survival outcomes. Thus, we compared oncologic treatment and survival outcomes for patients in Ontario with cup against those for a cohort of patients with metastatic cancer of known primary site.

Methods

Using the Ontario Cancer Registry and the Same-Day Surgery and Discharge Abstract databases maintained by the Canadian Institute for Health Information, we identified all Ontario patients diagnosed with metastatic cancer between 1 January 2000 and 31 December 2005. Ontario Health Insurance Plan treatment records were linked to identify codes for surgery, chemotherapy, or therapeutic radiation related to oncology. Multivariable Cox regression models were constructed, adjusting for histology, age, sex, and comorbidities.

Results

In 45,347 patients (96.3%), the primary tumour site was identifiable, and in 1743 patients (3.7%), cup was diagnosed. Among the main tumour sites, cup ranked as the 6th largest. The mean Charlson score was significantly higher (p < 0.0001) in patients with cup (1.88) than in those with a known primary (1.42). Overall median survival was 1.9 months for patients with cup compared with 11.9 months for all patients with a known-primary cancer. Receipt of treatment was more likely for patients with a known primary site (n= 35,012, 77.2%) than for those with cup (n = 891, 51.1%). Among patients with a known primary site, median survival was significantly higher for treated than for untreated patients (19.0 months vs. 2.2 months, p < 0.0001). Among patients with cup, median survival was also higher for treated than for untreated patients (3.6 months vs. 1.1 months, p < 0.0001).

Conclusions

In Ontario, patients with cup experience significantly lower survival than do patients with metastatic cancer of a known primary site. Treatment is associated with significantly increased survival both for patients with cup and for those with metastatic cancer of a known primary site.

Utility of Computed Tomography-guided Biopsy in Evaluation of Metastatic Spinal Lesions

INTRODUCTION

Computed tomography (CT)-guided biopsy of spine is currently a valuable diagnostic tool and effective technique for diagnosing and planning a proper therapeutic strategy for certain spinal lesions. The reported diagnostic accuracy of core biopsy ranges from 77% to 97%.

MATERIALS AND METHODS

We included all patients with spinal lesions suspicious of metastasis on magnetic resonance imaging, who presented between May 2012 and April 2014 and underwent CT-guided biopsy in our study. A total of thirty patients with spinal lesions were evaluated.

RESULTS

Majority presented in the seventh decade of their life (average age = 53.93; age range = 10-72 years). Male:female ratio was 1.5:1. Pain was the most common presenting symptom (100%). Lumbar spine was the most common site of lesion followed by dorsal spine. Biopsy is the gold standard in histopathological evaluation of spinal lesions. Metastatic lesion was diagnosed in 12 (40%) cases, plasmacytoma in 12 (40%) cases, non-Hodgkin's lymphoma in 2 (6.66%) cases, small round cell tumor in 1 (3.33%) case, nonspecific chronic inflammation in two patients, and necrosis with no viable cells in one patient. The most common malignancy to metastasize to spine was adenocarcinoma. The most common primary tumor of spine was plasmacytoma - multiple myeloma.

CONCLUSION

CCT-guided biopsy is a safe procedure, and no procedure-related complication was seen in any patient.

2018 consensus statement by the Spanish Society of Pathology and the Spanish Society of Medical Oncology on the diagnosis and treatment of cancer of unknown primary

Cancer of unknown primary (CUP) is defined as a heterogeneous group of tumours that present with metastasis, and in which attempts to identify the original site have failed. They differ from other primary tumours in their biological features and how they spread, which means that they can be considered a separate entity. There are several hypotheses regarding their origin, but the most plausible explanation for their aggressiveness and chemoresistance seems to involve chromosomal instability. Depending on the type of study done, CUP can account for 2–9% of all cancer patients, mostly 60–75 years old. This article reviews the main clinical, pathological, and molecular studies conducted to analyse and determine the origin of CUP. The main strategies for patient management and treatment, by both clinicians and pathologists, are also addressed.

Lymph node cancer of the mediastinum with a putative necrotic primary lesion in the lung: a case report

Background

Although mediastinal lymph node cancer is presumed to originate in the lung, the primary site is usually unidentified, so the pathological course remains unclear. We recently encountered a case of mediastinal lymph node cancer having a putative primary lesion remaining in the lung as a necrotic focus.

Case presentation

The patient was a 56-year-old man who visited our department because computed tomography screening had revealed a nodular shadow in the lingular segment. However, on positron emission tomography, fluorine-18 deoxyglucose accumulation was detected in a subcarinal lymph node and not in the nodule in the lingular segment. Biopsy of the lung tumor and the lymph node was performed via minimal thoracotomy. Intraoperative pathologic examination showed necrosis alone and no malignant findings in the lung tumor. By contrast, carcinoma was detected in the lymph node. Additional subcarinal lymph node dissection was performed. Results of postoperative histopathologic examination indicated poorly differentiated adenocarcinoma of the subcarinal lymph node. Meanwhile, the nodule in the lingular segment was speculated to be a spontaneously resolved primary focus of lung cancer.

Conclusions

In this case, the primary lung cancer focus resolved spontaneously after lymph node metastasis, explaining the pathogenesis underlying mediastinal lymph node cancer of unknown primary site. For similar cases of malignancy, aggressive treatment, including surgery, is effective.

Predictors of care for patients with cancer of unknown primary site in three Australian hospitals

AIM

Cancer of unknown primary site (CUP) is a medically challenging malignancy with a poor prognosis. We describe an incident tertiary CUP patient cohort and identify factors predictive of specific types of health care.

METHODS

We reviewed the medical records of 217 patients diagnosed with CUP (2006-2011) in three public hospitals in New South Wales, Australia. We systematically abstracted data and performed multivariable logistic regression to identify factors predictive of tumor biopsy, surgery, chemotherapy, radiotherapy and palliative care.

RESULTS

The median age at CUP diagnosis was 75 years (range 23-98) and 52% were male. The most common mode of presentation was emergency department admission (57%). Serum tumor markers were performed in 42%, fine needle aspiration alone in 15% and core biopsy in 52%. Younger age, health service referral, oncologist review and a family history of cancer predicted receipt of a biopsy (77%). Cancer-related surgery (17%) was more likely in younger patients, those presenting with pain, and those with single lymph node metastases. Younger age and good performance score predicted receipt of chemotherapy (22%). The location of metastases predicted receipt of radiotherapy (28%). Older age, emergency presentation, poor performance score and no oncology review predicted receipt of palliative care only (52%); 77% were referred for palliative care during hospitalization.

CONCLUSION

The determinants of care were generally consistent with international CUP clinical guidelines. Areas of future research include potential underinvestigation and undertreatment of older patients, overuse of certain low-value diagnostic tests, suboptimal use of immunohistochemistry and mammography and underreferral to palliative care.

Precision medicine based on epigenomics: the paradigm of carcinoma of unknown primary

Epigenetic alterations are a common hallmark of human cancer. Single epigenetic markers are starting to be incorporated into clinical practice; however, the translational use of these biomarkers has not been validated at the 'omics' level. The identification of the tissue of origin in patients with cancer of unknown primary (CUP) is an example of how epigenomics can be incorporated in clinical settings, addressing an unmet need in the diagnostic and clinical management of these patients. Despite the great diagnostic advances made in the past decade, the use of traditional diagnostic procedures only enables the tissue of origin to be determined in ∼30% of patients with CUP. Thus, development of molecularly guided diagnostic strategies has emerged to complement traditional procedures, thereby improving the clinical management of patients with CUP. In this Review, we present the latest data on strategies using epigenetics and other molecular biomarkers to guide therapeutic decisions involving patients with CUP, and we highlight areas warranting further research to engage the medical community in this unmet need.

Utility of Genomic Analysis In Circulating Tumor DNA from Patients with Carcinoma of Unknown Primary

Carcinoma of unknown primary (CUP) is a rare and difficult-to-treat malignancy, the management of which might be improved by the identification of actionable driver mutations. We interrogated 54 to 70 genes in 442 patients with CUP using targeted clinical-grade, next-generation sequencing of circulating tumor DNA (ctDNA). Overall, 80% of patients exhibited ctDNA alterations; 66% (290/442) ≥1 characterized alteration(s), excluding variants of unknown significance. TP53-associated genes were most commonly altered [37.8% (167/442)], followed by genes involved in the MAPK pathway [31.2% (138/442)], PI3K signaling [18.1% (80/442)], and the cell-cycle machinery [10.4% (46/442)]. Among 290 patients harboring characterized alterations, distinct genomic profiles were observed in 87.9% (255/290) of CUP cases, with 99.7% (289/290) exhibiting potentially targetable alterations. An illustrative patient with dynamic changes in ctDNA content during therapy and a responder given a checkpoint inhibitor-based regimen because of a mismatch repair gene anomaly are presented. Our results demonstrate that ctDNA evaluation is feasible in CUP and that most patients harbor a unique somatic profile with pharmacologically actionable alterations, justifying the inclusion of noninvasive liquid biopsies in next-generation clinical trials. Cancer Res; 77(16); 4238-46. ©2017 AACR.

Cancers of unknown primary diagnosed during hospitalization: a population-based study

Background

Cancers of Unknown Primary (CUP) are the 3-4^th most common causes of cancer death and recent clinical guidelines recommend that patients should be directed to a team dedicated to their care. Our aim was to inform the care of patients diagnosed with CUP during hospital admission.

Methods

Descriptive study using hospital admissions (Scottish Morbidity Record 01) linked to cancer registrations (ICD-10 C77-80) and death records from 1998 to 2011 in West of Scotland, UK (population 2.4 m). Cox proportional hazards models were used to assess effects of baseline variables on survival.

Results

Seven thousand five hundred ninety nine patients were diagnosed with CUP over the study period, 54.4% female, 67.4% aged ≥ 70 years, 36.7% from the most deprived socio-economic quintile. 71% of all diagnoses were made during a hospital admission, among which 88.6% were emergency presentations and the majority (56.3%) were admitted to general medicine. Median length of stay was 15 days and median survival after admission 33 days. Non-specific morphology, emergency admission, age over 60 years, male sex and admission to geriatric medicine were all associated with poorer survival in adjusted analysis.

Conclusions

Patients with a diagnosis of CUP are usually diagnosed during unplanned hospital admissions and have very poor survival. To ensure that patients with CUP are quickly identified and directed to optimal care, increased surveillance and rapid referral pathways will be required.

Impact of 3T multiparametric MRI and FDG-PET-CT in the evaluation of occult primary cancer with cervical node metastasis

Background

This study aimed to determine the ability of multimodal evaluation with multiparametric 3T-MRI (MPMRI) and positron emission tomography - computed tomography (PET/CT) to detect cancer of unknown primary origin (CUP) with neck lymph node (LN) metastasis.

Methods

The study group comprised 38 retrospectively analysed consecutive patients with LN metastasis in the head and neck (HN) region without known primary tumours (PTs). Statistical values of 3T-MRI and of FDG-PET/CT scans were evaluated.

Results

Of the 38 CUPs, conventional native T1-, T2-weighted and STIR sequences detected 6 PTs. Native sequences plus diffusion-weighted imaging (DWI) found 14-, and with fat suppression contrast-enhanced T1-weighted measurement as well as with the complex MPMRI found 15 primaries and with PET/CT 17 CUPs could be evaluated, respectively. The detection rates were 15.8, 36.8, 39.5, 39.5 and 44.7 % for conventional native MRI, native plus DWI, native with contrast-enhanced MRI (CE-MRI), for MPMRI, and for PET/CT, respectively. The overall detection rate proved by histology was 47.4 %. PET/CT provided the highest sensitivity (Sv: 94.4 %) but a lower specificity (Sp: 65.0 %), using MPMRI (Sv: 88.2 %) the specificity increased to 71.4 %. DWIincreased specificity of the native sequences (Sp: 76.2 %). Conventional native sequences plus DWI as well as 3T-MPMRI and PET/CT were same accurate (Acc: 79.0 %) and had similar likelihood ratio (LR: 3.42, 3.03 and 2.62) in detecting unknown PT sites.

Conclusions

The accuracy of FDG-PET/CT and MPMRI in case of CUP in finding the primary cancer in the neck regions is identical. While using PET/CT whole body information can be obtained in one examination. MPMRI shows the local soft tissue status more accurately. In cases of CUP PET/CT should be the first method of choice if it is available. MPMRI can clarify the exact primary tumor stage, and it can be advantageous in clarifying the prognostic factors, which is necessary in case of advanced tumor stage and when surgery is under consideration. In case low N stage is likely after the clinical examination and wait and see policy can be considered, MPMRI is recommended, and in this case the significance the of radiation free MPMRI is increasing.

Electronic supplementary material

The online version of this article (doi:10.1186/s40644-016-0097-x) contains supplementary material, which is available to authorized users.

Vertebral Metastasis as the Initial Manifestation of Colon Cancer

Oncology guidelines currently recommend against performing colonoscopies in the workup of adenocarcinoma of unknown primary unless colonic malignancy is otherwise suggested by clinical signs or symptoms. We present 2 cases of metastatic colonic adenocarcinoma that presented only with neurologic symptoms from vertebral metastasis. Although bony metastases are a rare presentation of colon cancer and colonoscopy is not warranted in the initial workup of adenocarcinoma of unknown primary, we describe these cases as a reminder that bony metastases do not rule out a colon cancer diagnosis.

Diagnostic Accuracy of 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography in the Evaluation of Carcinoma of Unknown Primary

Objective:

Detection of primary tumor site in patients with carcinoma of unknown primary (CUP) syndrome has always been a diagnostic dilemma, necessitating extensive workup. Early detection of primary tumor site coupled with specific therapy improves prognosis. The low detection rate of the primary tumor site can be attributed to the biological behavior or the small size of the primary tumor to be detected by conventional imaging. The objective of this study was to evaluate the diagnostic accuracy of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography-computed tomography (PET-CT) in detecting CUP.

Methods:

A retrospective, cross-sectional analysis of 100 PET-CT scans of patients with CUP syndrome between November 2009 and December 2013 was performed. Eighteen patients whose final histopathology results could not be obtained for correlation were excluded from analysis. The hypermetabolic sites were assessed in correlation with histopathology. The diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive values were assessed for PET-CT.

Results:

Out of the 82 patients, primary tumor was correctly identified in 57.3% patients by ¹⁸F-FDG PET-CT (true positive). The PET-CT scan results were negative for primary site localization in 15% of patients (false negative). While 21% had true negative results, 7.3% displayed false positive results. PET-CT scan upstaged the disease in 27% cases. Overall, the diagnostic accuracy was found to be 78%, sensitivity 80%, specificity 74%, positive predictive value 88.7% and negative predictive value 59%.

Conclusion:

Our data supports the utility of ¹⁸F-FDG PET-CT scan in the localization and staging of CUP syndrome.

Evolving landscape of tumor molecular profiling for personalized cancer therapy: a comprehensive review

INTRODUCTION

Tumour molecular profiling has been at the crossroads of large-scale integrative genomic studies and major clinical trials over the past 5 years and has provided roadmaps for better disease stratification and therapeutic management.

AREAS COVERED

We review the landscape of precision oncology trials in Asia, Europe and the United States, and emerging insights gained from recently reported studies such as the SHIVA and CUSTOM trials. Changes in the molecular portraits of human cancers and the immune contexture of the tumor microenvironment during treatment may predict the course of tumor progression, including the development of treatment resistance. 'Liquid biopsy' approaches that harness circulating tumor cells, cell-free DNA and exosomes may provide a non-invasive means of monitoring the parent tumor in real-time. Several molecular signatures are being evaluated as biomarkers for emerging immunologic approaches, such as the mismatch-repair deficiency status and nonsynonymous mutation burden in anti-PD-1 immune checkpoint blockade. Finally, we review the current actionability and future clinical impact of multigene panel and next-generation sequencing (NGS)-based profiling.

EXPERT OPINION

In the future, molecular profiling may help to fulfill unmet needs for predictive biomarkers in novel immunotherapeutic approaches, while ongoing precision trials are laying the foundations for clinical uptake of NGS testing.

Multiple Bony Metastatic Lesions and Evaluation of Primary: Case Records of a Cancer Research Centre

During 2012-13, we diagnosed 4 patients with extensive skeletal tuberculosis (TB) who were referred to us as cases of bony metastasis with unknown primary. Radiological investigations done outside favoured a diagnosis of disseminated malignancy. Positron emission tomography/computed tomography (PET/CT) scan performed in our institute for localization of primary lesion also suggested metastatic disease. There was no evidence of malignancy on histo-pathological examination (HPE) of the involved sites. The diagnosis of TB was established on characteristics HPE. This article highlights the diagnostic dilemma of PET/CT in cases of TB versus malignancy and the importance of HPE for reaching an accurate diagnosis.

Comprehensive Genomic Profiling of Carcinoma of Unknown Primary Site: New Routes to Targeted Therapies

IMPORTANCE

For carcinoma of unknown primary site (CUP), determining the primary tumor site may be uninformative and often does not improve outcome.

OBJECTIVE

To discover opportunities for targeted therapies in patients with CUP not currently searched for in routine practice.

DESIGN, SETTING, AND PARTICIPANTS

Comprehensive genomic profiling on 200 CUP formalin-fixed paraffin-embedded specimens (mean, 756× coverage) using the hybrid-capture-based FoundationOne assay at academic and community oncology clinics.

MAIN OUTCOMES AND MEASURES

Presence of targetable genomic alterations (GAs) in CUP and responses to targeted therapies.

RESULTS

There were 125 adenocarcinomas of unknown primary site (ACUPs) and 75 carcinomas of unknown primary site without features of adenocarcinoma (non-ACUPs). At least 1 GA was found in 192 (96%) of CUP specimens, with a mean (SD) of 4.2 (2.8) GAs per tumor. The most frequent GAs were in TP53 (110 [55%]), KRAS (40 [20%]), CDKN2A (37 [19%]), MYC (23 [12%]), ARID1A (21 [11%]), MCL1 (19 [10%]), PIK3CA (17 [9%]), ERBB2 (16 [8%]), PTEN (14 [7%]), EGFR (12 [6%]), SMAD4 (13 [7%]), STK11 (13 [7%]), SMARCA4 (12 [6%]), RB1 (12 [6%]), RICTOR (12 [6%]), MLL2 (12 [6%]), BRAF (11 [6%]), and BRCA2 (11 [6%]). One or more potentially targetable GAs were identified in 169 of 200 (85%) CUP specimens. Mutations or amplifications of ERBB2 were more frequent in ACUPs (13 [10%]) than in non-ACUPs (3 [4%]). Alterations of EGFR (10 [8%] vs 2 [3%]) and BRAF (8 [6%] vs 3 [4%]) were more common in ACUPs than in non-ACUPs. Strikingly, clinically relevant alterations in the receptor tyrosine kinase (RTK)/Ras signaling pathway including alterations in ALK, ARAF, BRAF, EGFR, FGFR1, FGFR2, KIT, KRAS, MAP2K1, MET, NF1, NF2, NRAS, RAF1, RET, and ROS1 were found in 90 (72%) ACUPs but in only 29 (39%) non-ACUPs (P < .001).

CONCLUSIONS AND RELEVANCE

Almost all CUP samples harbored at least 1 clinically relevant GA with potential to influence and personalize therapy. The ACUP tumors were more frequently driven by GAs in the highly druggable RTK/Ras/mitogen-activated protein kinase (MAPK) signaling pathway than the non-ACUP tumors. Comprehensive genomic profiling can identify novel treatment paradigms to address the limited options and poor prognoses of patients with CUP.

[(177)Lu-DOTA](0)-D-Phe(1)-Tyr(3)-Octreotide ((177)Lu-DOTATOC) For Peptide Receptor Radiotherapy in Patients with Advanced Neuroendocrine Tumours: A Phase-II Study

PURPOSE

To characterise efficacy and safety of (177)Lu-DOTATOC as agent for peptide receptor radiotherapy (PRRT) of advanced neuroendocrine tumours (NET).

PATIENTS AND METHODS

Fifty-six subjects with metastasized and progressive NET (50% gastroenteral, 26.8% pancreatic, 23.2% other primary sites) treated consecutively with (177)Lu-DOTATOC were analysed retrospectively. Subjects were administered (177)Lu-DOTATOC (mean 2.1 cycles; range 1-4) as 7.0GBq (median) doses at three-monthly intervals. Efficacy was analysed using CT and/or MRI according to RECIST 1.1 criteria and results were stratified for the number of administered cycles and the primary tumour origin.

RESULTS

In the total NET population (A), median progression-free (PFS) and overall survival (OS) were 17.4 and 34.2 months, respectively, assessed in a follow-up time (mean ± SD) of 16.1 ± 12.4 months. In patients receiving more than one cycle, mean follow-up time was 22.4 ± 11.0 months for all NETs (B) and PFS was 32.0 months for all NETs (B), 34.5 months for GEP-NET (C), and 11.9 months for other NETs (D). Objective response rates (Complete/Partial Responses) were 33.9%, 40.6%, 54.2%, and 0% for A, B, C, and D groups, respectively, while disease control rates in the same were 66.1%, 93.8%, 100%, and 75%. Complete responses (16.1%, 18.8% and 25.0% for groups A, B and C) were high, 78% of which were maintained throughout the follow up. There were no serious adverse events. One case of self-limiting grade 3 myelotoxicity was reported. Although 20% of patients had mild renal insufficiency at baseline, there was no evidence of exacerbated or de novo renal toxicity after treatment.

CONCLUSION

(177)Lu-DOTATOC is a novel agent for PRRT with major potential to induce objective tumour responses and sustained disease control in progressive neuroendocrine tumours, even when administered in moderate activities. The observed safety profile suggests a particularly favourable therapeutic index, including in patients with impaired bone marrow or renal function, which reflects a uniquely low uptake of (177)Lu-DOTATOC by normal organs.

Carcinoma of unknown primary and paraneoplastic dermatomyositis

Dermatomyositis is known to be associated with neoplastic disorders, however the presentation of carcinoma of unknown primary as dermatomyositis is rare. We describe a case index of 50-year-old female who presented with enlarged inguinal lymph nodes accompanied with symmetric proximal muscle weakness and erythematous plaques. Conventional basic work-up did not reveal the diagnosis, however, positron emission tomography-computed tomography and re-staining of the pathology specimen suggested the ovaries as the primary site. Chemotherapy including carboplatin paclitaxel and bevacizumab led to complete response of disease and improvement in the dermatomyositis. The present case emphasizes the importance of a thorough directed evaluation for the underlying cancer in patients with carcinoma of unknown primary presenting as dermatomyositis. We further provide an up-to-date detailed review of published data describing these clinical entities.

Identification and survival outcomes of a cohort of patients with cancer of unknown primary in Ontario, Canada

BACKGROUND

Cancer of unknown primary origin (CUP) is defined by the presence of pathologically identified metastatic disease without clinical or radiological evidence of a primary tumour. Our objective was to identify incident cases of CUP in Ontario, Canada, and determine the influence of histology and sites of metastases on overall survival (OS).

MATERIAL AND METHODS

We used the Ontario Cancer Registry (OCR) and the Same-Day Surgery and Discharge Abstract Database (SDS/DAD) to identify patients diagnosed with CUP in Ontario between 1 January 2000, and 31 December 2005. Patient diagnostic information, including histology and survival data, was obtained from the OCR. We cross-validated CUP diagnosis and obtained additional information about metastasis through data linkage with the SDS/DAD database. OS was assessed using Cox regression models adjusting for histology and sites of metastases.

RESULTS

We identified 3564 patients diagnosed with CUP. Patients without histologically confirmed disease (n = 1821) had a one-year OS of 10.9%, whereas patients with confirmed histology (n = 1743) had a one-year OS of 15.6%. The most common metastatic sites were in the respiratory or digestive systems (n = 1603), and the most common histology was adenocarcinoma (n = 939). Three-year survival rates were 3.5%, 5.3%, 41.6% and 3.6% among adenocarcinoma, unspecified carcinoma, squamous cell carcinoma and undifferentiated histology, respectively. Three-year survival rates were 40%, 2.4%, 8.0% and 4.6% among patients with metastases localised to lymph nodes, the respiratory or digestive systems, other specified sites, and unspecified sites, respectively.

CONCLUSION

CUP patients in Ontario have a poor prognosis. Some subgroups may have better survival rates, such as patients with metastases localised to lymph nodes and patients with squamous cell histology.

Comprehensive tumor profiling identifies numerous biomarkers of drug response in cancers of unknown primary site: analysis of 1806 cases

Background

Cancer of unknown primary (CUP) accounts for approximately 3% of all malignancies. Despite extensive laboratory and imaging efforts, the primary site usually cannot be unequivocally confirmed, and the treatment for the most part remains empirical. Recently, identification of common cancer pathway alterations in diverse cancer lineages has offered an opportunity to provide targeted therapies for patients with CUP, irrespective of the primary site.

Patients and Methods

1806 cancers of unknown primary were identified among more than 63,000 cases profiled at Caris Life Sciences. Multiplatform profiling of the tumor samples included immunohistochemistry, gene sequencing and in situ hybridization methods in an effort to identify changes in biomarkers that are predictive of drug responses.

Results

Biomarkers associated with a potential drug benefit were identified in 96% of cases. Biomarkers identified included those associated with potential benefit in nearly all classes of approved cancer drugs (cytotoxic, hormonal, targeted biological drugs). Additionally, biomarkers associated with a potential lack of benefit were identified in numerous cases, which could further refine the management of patients with CUP.

Conclusion

Comprehensive biomarker profiling of CUP may provide additional choices in treatment of patients with these difficult to treat malignancies.

Lung Cancer Detected 5 Years after Resection of Cancer of Unknown Primary in a Mediastinal Lymph Node: A Case Report and Review of Relevant Cases from the Literature

We report the rare and interesting case of a primary lung cancer detected 5 years after cancer of unknown primary (CUP) of a mediastinal lymph node (LN) was resected. A 40-year-old male was diagnosed with adenocarcinoma of unknown primary in a mediastinal lymph node after resection of the mediastinal tumor. Five years after resection of the CUP in mediastinal LN, a small, abnormal nodular shadow in left upper lobe was detected by chest CT. This pulmonary tumor was diagnosed as a lung adenocarcinoma. The pathological and immunohistological findings of the resected pulmonary tumor resembled those of the LN resected 5 years before. We speculated that the pulmonary lesion represented primary lung cancer that enlarged later than the metastatic mediastinal LN. This case illustrates the importance of careful observation and long-term follow-up in patients treated for CUP of a thoracic LN.

Diagnostic Imaging Efficacy In Metastases From Unknown Primary Site--Own Material

Cancer of Unknown Primary Origin (CUPO) is defined by the presence of metastatic lesions, diagnosed by means of cytological or pathological evaluation, for which no primary site can be detected during a thorough examination. The clinical investigation, directed at locating the site of the neoplastic lesion, is determined by the results of laboratory tests, imaging procedures, and pathological examinations. It is also essential to conduct a complete medical history and thorough physical examination. The detection of the primary site allowed to introduce specific therapy, which can offer clinical benefits, considering a favorable prognosis. The aim of the study was to assess the range of diagnostic procedures performed in patients with CUPO and efficacy in identifying the primary lesion.

MATERIAL AND METHODS

Retrospective analysis comprised a group of 29 patients with CUPO, operated between January, 2002 and December, 2011, at the Department of Surgical Oncology, Medical University in Łódź. The study group comprised 16 male and 13 female patients; median age at presentation was 58.3 years (ranging between 30-79 years).

RESULTS

Detailed diagnostic management depending on the location of metastatic lesions and their histological type was performed in 20 of the 29 study patients (69%). Considering the remaining 9 (31%) patients detailed diagnostics was not performed, due to the patients' poor general condition. In 55% (11/20) of patients subject to detailed diagnostics, the primary neoplastic lesion was determined.

CONCLUSIONS

Considering the study group, most patients with cancer of unknown primary origin were characterized by a favorable prognosis, which justified thorough diagnostics, in order to establish the primary neoplastic lesion. The introduction of diagnostic examinations enabled to identify the primary site of the tumor in more than 50% of patients. With the development of imaging methods one can expect improvement of unsatisfactory results, considering the detection of primary neoplastic foci.

Health service utilisation and investigations before diagnosis of cancer of unknown primary (CUP): A population-based nested case-control study in Australian Government Department of Veterans' Affairs clients

BACKGROUND

Population-based data on the use of health services and diagnostic investigations for patients with cancer of unknown primary (CUP) is scarce. It is uncertain whether the pathways to diagnosis are different for CUP compared to other cancers.

METHODS

We performed a population-based nested matched case-control study using linked routinely collected records for Australian Government Department of Veterans' Affairs clients, 2004-2007. We compared health care consultations, hospitalisations, emergency department visits, and diagnostic procedures in the three months prior and the month of diagnosis for 281 clients registered with a diagnosis of CUP (C809) and 1102 controls randomly selected from clients registered with a first diagnosis of metastatic cancer of known primary.

RESULTS

Overall, the median age at cancer diagnosis was 83 years. CUP patients were slightly older and had significantly more comorbidities prior to diagnosis than those with known primary. Compared to known primary, a diagnosis of CUP was significantly more likely after an emergency department visit, less specialist input, fewer invasive diagnostic procedures such as resection or endoscopy, and more non-invasive procedures such as magnetic resonance imaging. There were no differences in primary care or allied health consultations and hospitalisations.

CONCLUSIONS

This health care pathway suggests delayed recognition of cancer and scope for improvement in the medical management of high-risk individuals presenting to primary care. The pattern of diagnostic investigations reveals under-investigation in some CUP patients but this is likely to reflect recognition of limited treatment options and poor prognosis and is consistent with clinical guidelines.

Cancer of Unknown Primary origin in the genomic era: Elucidating the dark box of cancer

Cancer of Unknown Primary (CUP) comprises a heterogeneous disease group with diagnosis of metastatic malignancy in the absence of an identifiable primary site after diagnostic work up. CUP may either resemble a specific primary tumor site sharing common clinicopathological characteristics and prognosis, or present as a distinct disease entity with undifferentiated pathological features, usually bearing dismal prognosis. Diagnosis and management have traditionally been based on clinicopathological characteristics and therapeutic strategies have been mainly empirical. In the last decade, the advent of massive gene sequencing and the advances in genomic technologies have shed light on the genomic landscape of CUP. Several gene panel tests are currently commercially available and are used in an effort to correlate the genomic characteristics of a specific CUP tumor to those of a known primary tumor, guiding thus therapeutic management. Nevertheless, these efforts are hampered by the rarity of CUP and the inability to validate the results of such tests due to the paucity of randomized clinical trials. In the current work, we provide an overview of CUP with emphasis on the impact of the genome sequencing technologies on diagnosis and management of these tumors. We also discuss potential implications of genomics for the future treatment of CUP and address the challenges of the implementation of these therapeutic strategies in routine clinical practice.

Dramatic response of chemotherapy for cancer of unknown primary origin of sarcomatoid carcinoma producing granulocyte colony-stimulating factor

Cancer of unknown primary origin (CUP) which is usually diagnosed based on the histological type of metastatic site has marked heterogeneous characteristics. Sarcomatoid carcinoma defined as CUP has not been reported according to our literature survey. A 59-year-old man presented with enlarged multiple thoracic lymph nodes, huge splenomegaly and nodules in left temporal lobe of the brain. The histopathological diagnosis of lymph node and spleen was sarcomatoid carcinoma. However, all extensive diagnostic examinations could not detect a site of primary origin. The laboratory data showed marked leukocytosis with increased serum granulocyte colony-stimulating factor (G-CSF). Therefore, the patient was finally diagnosed of CUP of sarcomatoid carcinoma producing G-CSF. After gamma knife treatment for brain metastases, two regimens of taxan-based chemotherapy (carboplatin and paclitaxel, gemcitabine and docetaxel) were administered, with no effect but further tumor progression. Splenectomy for avoiding splenic rupture was performed. As the third line chemotherapy, the combination consisting of doxorubicin and ifosfamide was administered and showed a good therapeutic effect and normalized white blood cell count and serum G-CSF level. He achieved complete remission after three cycles. Herein we present an extremely rare case of CUP of sarcomatoid carcinoma producing G-CSF. Our case suggests the importance of chemotherapy including doxorubicin and ifosfamide, and multimodal therapeutic strategy for this aggressive disease.

Patients with cancer of unknown primary: a retrospective analysis of 223 patients with adenocarcinoma or undifferentiated carcinoma

BACKGROUND

Cancer of unknown primary (CUP) now accounts for 2-3% of all fatal cases of cancer in Germany. Histologically, most of these tumors are either adenocarcinoma or undifferentiated carcinoma. Scant data on their clinical features and prognosis are now available, and the published survival times are highly variable. In this article, we document and analyze our own experience with CUP to date.

METHOD

We took all 223 patients with CUP (adenocarcinoma or undifferentiated carcinoma) whom we saw in our CUP clinic from 2006 to 2010 as an unaltered sample for retrospective analysis of clinical data and overall survival. We performed the analysis with Kaplan-Meier plotting, log-rank testing, and Cox regression.

RESULTS

With a median follow-up time of 32.9 months, the median survival from the time of diagnosis was 16.5 months. Metastases were most commonly found in the lymph nodes, followed by the liver, bones, and lungs. The main pre-treatment prognostic variables that remained significant after adjustment for multiple testing were the Eastern Cooperative Oncology Group (ECOG) score for overall state of health and the number of organ systems involved. These variables were used to construct a practice-oriented risk stratification.

CONCLUSION

In patients with adeno- or undifferentiated CUP syndrome, the ECOG score and the number of organ systems involved are important risk factors.

Indolent metastatic squamous cell carcinoma of unknown primary in the intrathoracic lymph node: a case report and review of the literatures

Metastatic squamous cell carcinoma from a cancer of unknown primary (CUP) affecting the intrathoracic lymph node is very rare. We reported a case of metastatic squamous cell carcinoma in the hilar and interlobar lymph node from a patient with CUP and reviewed the associated literature. Abnormal mass in the right hilar area was incidentally detected. A chest computed tomography scan showed a 2.5-cm diameter mass in the right hilum that had changed little in size for 3 years. The patient underwent a right pneumonectomy and mediastinal lymph node dissection. A metastatic squamous cell carcinoma in the hilar and interlobar lymph nodes without a primary lung or other lesion was diagnosed. The patient received adjuvant chemotherapy for a diagnosis of T0N1M0 lung cancer.

Targeting Src-mediated Tyr216 phosphorylation and activation of GSK-3 in prostate cancer cells inhibit prostate cancer progression in vitro and in vivo

Recent studies suggest a positive correlation between glycogen synthase kinase-3 (GSK-3) activation and tumor growth. Currently, it is unclear how both Akt that inhibits GSK-3 and active GSK-3 are maintained concurrently in tumor cells. We investigated the role of GSK-3 and the existence of an Akt-resistant pathway for GSK-3 activation in prostate cancer cells. Our data show that Src, a non-receptor tyrosine kinase is responsible for Y216GSK-3 phosphorylation leading to its activation even when Akt is active. Experiments involving mouse embryonic fibroblasts lacking cSrc, Yes and Fyn, as well as Src activity modulation in prostate cancer cells with constitutively active (CA-Src) and dominant negative Src (DN-Src) plasmids demonstrated the integral role of Src in Y216GSK-3 phosphorylation and activity modulation. Inhibition of GSK-3 with SB415286 in PC3 cells resulted in impaired motility, proliferation and colony formation. Treatment of PC3 cells with the Src inhibitor dasatinib reduced Y216GSK-3 phosphorylation and inhibited proliferation, invasion and micrometastasis in vitro. Dasatinib treatment of athymic nude mice resulted in impaired growth of PC3 cell tumor xenograft. Together, we provide novel insight into the Src-mediated Y216GSK-3 phosphorylation and activation in prostate cancer cells and reveal the potential benefits of targeting Src-GSK-3 axis using drugs such as dasatinib.

Comparison of different prostatic markers in lymph node and distant metastases of prostate cancer

Prostate cancer is mostly diagnosed at an early stage; however, some tumors are diagnosed in a metastatic stage as cancer of unknown primary origin. In order to allow specific treatment in the case of prostate cancer presenting as cancer of unknown primary origin, it is important to determine the tumor origin. Prostate-specific antigen is used as a diagnostic marker for prostate cancer but the expression declines with progression to castration-resistant prostate cancer. Aim of this study was to identify the most informative marker constellation, which is able to detect metastatic prostate cancer at high sensitivity. The widely used prostate cancer markers such as prostate-specific antigen, prostate-specific acid phosphatase, androgen receptor, prostate-specific membrane antigen, prostein, and ETS-related gene were investigated for their sensitivity to detect prostatic origin of metastases. Expression of prostate-specific antigen, prostate-specific acid phosphatase, androgen receptor, prostate-specific membrane antigen, prostein, and ETS-related gene was determined on archived tissue specimens consisting of benign prostatic tissue (n=9), primary prostate cancer (n=79), lymph node metastases (n=58), and distant metastases (n=39) using immunohistochemistry. The staining intensity was categorized as negative (0), weak (1), moderate (2), and strong (3). All markers except ETS-related gene were able to detect at least 70% of lymph node metastases and distant metastases, with prostate-specific antigen, androgen receptor, and prostate-specific membrane antigen having the highest sensitivity (97%, 91%, and 94%, respectively). A further increase of the sensitivity up to 98% and 100% could be achieved by the combination of prostate-specific antigen, prostate-specific membrane antigen, or androgen receptor for lymph node metastases and for distant metastases, respectively. The same sensitivity could be reached by combining prostate-specific membrane antigen and prostein. Our data show that a combined staining of at least two prostate markers should be utilized to identify metastases as originating from prostate cancer.

Male pelvic squamous cell carcinoma of unknown primary origin

Pelvic squamous cell carcinoma of unknown primary origin has been described in several case reports of female patients. However, there have been no published reports describing male patients with pelvic squamous cell cancer of unknown primary origin. Our case describes a 52-year-old man who presented with right buttock pain, rectal urgency, and constipation. His physical examination demonstrated tenderness to palpation around his gluteal folds. Computed tomography scan of his abdomen and pelvis demonstrated a large mass in his retroperitoneum. The mass was determined to be squamous cell carcinoma of unknown primary origin. Additionally, the patient had small nodules in his right lower lung lobe and right hepatic lobe. The patient was treated with concomitant chemoradiation, including cisplatin and intensity-modulated radiation therapy, followed by carboplatin and paclitaxel. The patient achieved partial remission, in which he remained one year after his presentation. Our case is consistent with the literature which suggests that squamous cell carcinoma of unknown primary origin occurring outside of the head and neck region may have a more favorable prognosis than other carcinomas of unknown primary origin. Further studies are necessary to determine the most appropriate work-up, diagnosis, and optimal treatment strategies.

Clinical guideline SEOM: cancer of unknown primary site

Cancer of unknown primary site is a histologically confirmed cancer which is manifested in advanced stage, with no identifiable primary site after the use of standard diagnostic procedures. Patients are initially placed into one of categories based upon the examination of the initial biopsy: adenocarcinoma, squamous cell carcinoma, neuroendocrine carcinoma and poorly differentiated carcinoma. Appropriate patient management requires an understanding of several clinicopathologic features that help to identify several subsets of patients with more responsive tumors.

[Importance of nuclear medicine diagnostics in CUP syndrome]

CLINICAL/METHODICAL ISSUE

The diagnostic work-up in patients with carcinoma of unknown primary (CUP) syndrome is extensive, highly time-consuming and cost-intensive and ultimately often fails to detect a primary site.

STANDARD RADIOLOGICAL METHODS

In this context chest X-ray and computed tomography (CT) have been used as standard imaging modalities in CUP syndrome.

METHODOLOGICAL INNOVATIONS

Since the introduction of positron emission tomography (PET) evaluation of tumor vitality has become possible. Furthermore, PET-CT hybrid scanners allow the combination of functional and morphological imaging.

PERFORMANCE

Several meta-analyses have reported an additional overall detection rate between 24.5 % and 44 % by either PET or PET-CT. Metastatic localization (cervical versus extracervical) did not influence the performance. The sensitivity was usually high (> 80 %) but specificity was moderate ranging from 68 % to 88 % at best. If mentioned, the results obtained by fluorodeoxyglucose (FDG)-PET significantly changed the clinical management in approximately one third of the patients studied. In a direct comparison with PET alone, PET-CT did not depict significantly more primary tumors but was able to reduce false positive findings.

ACHIEVEMENTS

To determine the real additional value of PET-CT in the diagnosis of CUP syndrome large prospective studies with more uniform inclusion criteria are needed. Despite the capabilities of FDG-PET-CT there is as yet no evidence that a potentially improved diagnostic algorithm is translated into a better patient outcome.

PRACTICAL RECOMMENDATIONS

Nevertheless, FDG-PET-CT should be performed in all CUP patients where conventional imaging failed to detect a primary site or the results are equivocal. In CUP patients with cervical lymph node metastases PET-CT should be carried out prior to panendoscopy to reduce the number of false negative biopsies.