Clinical guideline SEOM: cancer of unknown primary site

Cancer metastasis under the magnifying glass of epigenetics and epitranscriptomics

Most of the cancer-associated mortality and morbidity can be attributed to metastasis. The role of epigenetic and epitranscriptomic alterations in cancer origin and progression has been extensively demonstrated during the last years. Both regulations share similar mechanisms driven by DNA or RNA modifiers, namely writers, readers, and erasers; enzymes responsible of respectively introducing, recognizing, or removing the epigenetic or epitranscriptomic modifications. Epigenetic regulation is achieved by DNA methylation, histone modifications, non-coding RNAs, chromatin accessibility, and enhancer reprogramming. In parallel, regulation at RNA level, named epitranscriptomic, is driven by a wide diversity of chemical modifications in mostly all RNA molecules. These two-layer regulatory mechanisms are finely controlled in normal tissue, and dysregulations are associated with every hallmark of human cancer. In this review, we provide an overview of the current state of knowledge regarding epigenetic and epitranscriptomic alterations governing tumor metastasis, and compare pathways regulated at DNA or RNA levels to shed light on a possible epi-crosstalk in cancer metastasis. A deeper understanding on these mechanisms could have important clinical implications for the prevention of advanced malignancies and the management of the disseminated diseases. Additionally, as these epi-alterations can potentially be reversed by small molecules or inhibitors against epi-modifiers, novel therapeutic alternatives could be envisioned.

Diagnostic value of tumor markers in identifying favorable or unfavorable subsets in patients with cancer of unknown primary: a retrospective study

Background

Routine measurement of tumor markers is not recommended in daily clinical practice for patients with cancer of unknown primary (CUP). We evaluated the diagnostic value of tumor markers in identifying favorable or unfavorable subsets in patients with CUP.

Methods

We retrospectively reviewed the medical records of patients who were diagnosed with CUP between October 2010 and July 2015 at the National Cancer Center Hospital. The tumor markers of the patients were examined, including squamous cell carcinoma antigen, cytokeratin fraction, carcinoembryonic antigen, sialyl Lewis X, neuron-specific enolase, pro-gastrin-releasing peptide, α-fetoprotein, protein induced by vitamin K absence or antagonist II, prostate-specific antigen, soluble interleukin-2 receptor, carbohydrate antigen 19–9, cancer antigen 125, cancer antigen 15–3, NCC-ST-439 (ST439), elastase-1, human chorionic gonadotropin, and sialyl-Tn (STN).

Results

Among 199 patients with suspected CUP, 90 were diagnosed with confirmed CUP (12 in the favorable subset and 78 in the unfavorable subset). No tumor markers showed 100% sensitivity for unfavorable subsets. ST439 (p = 0.03) and STN (p = 0.049) showed 100% specificity for unfavorable subsets.

Conclusions

For patients with suspected CUP who show elevated ST439 or STN levels, the treatment strategy should be based on the premise that the patient is likely to be placed in the unfavorable subset.

Quantified CIN Score From Cell-free DNA as a Novel Noninvasive Predictor of Survival in Patients With Spinal Metastasis

Purpose: Most currently available scores for survival prediction of patients with bone metastasis lack accuracy. In this study, we present a novel quantified CIN (Chromosome Instability) score modeled from cfDNA copy number variation (CNV) for survival prediction. Experimental Design: Plasma samples collected from 67 patients with bone metastases from 11 different cancer types between November 2015 and May 2016 were sent through low-coverage whole genome sequencing followed by CIN computation to make a correlation analysis between the CIN score and survival prognosis. The results were validated in an independent cohort of 213 patients. Results: During the median follow-up period of 598 (95% CI 364-832) days until December 25, 2018, 124 (44.3%) of the total 280 patients died. Analysis of the discovery dataset showed that CIN score = 12 was the optimal CIN cutoff. Validation dataset showed that CIN was elevated (score ≥12) in 87 (40.8%) patients, including 5 (5.75%) with head and neck cancer, 11 (12.6%) with liver and gallbladder cancer, 11 (12.6%) with cancer from unidentified sites, 21 (24.1%) with lung cancer, 7 (8.05%) with breast cancer, 4 (4.60%) with thyroid cancer, 6 (6.90%) with colorectal cancer, 4 (4.60%) with kidney cancer, 2 (2.30%) with prostate cancer, and 16 (18.4%) with other types of cancer. Further analysis showed that patients with elevated CIN were associated with worse survival (p < 0.001). For patients with low Tokuhashi score (≤8) who had predictive survival of less than 6 months, the CIN score was able to distinguish patients with a median overall survival (OS) of 443 days (95% CI 301-585) from those with a median OS of 258 days (95% CI 184-332). Conclusion: CNV examination in bone metastatic cancer from cfDNA is superior to the traditional predictive model in that it provides a noninvasive and objective method of monitoring the survival of patients with spine metastasis.

Carcinoma of Unknown Primary in a Patient With Lynch Syndrome

Lynch syndrome is the most common form of hereditary colorectal cancer and is associated with an increased incidence of endometrial cancer, small bowel cancer, and other malignancies. The advent of immune checkpoint blockade, next-generation sequencing, and precision medicine molecular tumor boards have revolutionized the current treatment landscape for many cancers and allowed for more creative approaches to treating patients. In addition, tissue agnostic approvals have also served as valid treatment options for patients with otherwise untreatable cancers. In this report, we discuss the case of a 70-year-old woman with Lynch syndrome found to have retroperitoneal lymphadenopathy with p16-negative squamous cell carcinoma, diagnosed as carcinoma of unknown primary (CUP). To our knowledge, this is the first report of Lynch syndrome-associated squamous cell CUP. More research is needed on newly emerging cancer presentations in Lynch syndrome patients as they achieve longer lifespans.

Extensive diagnostic work-up for patients with carcinoma of unknown primary

Patients with carcinoma of unknown primary (CUP) present with metastatic disease without an identified primary tumour. The unknown site of origin makes the diagnostic work-up and treatment challenging. Since little information is available regarding diagnostic work-up and treatment in daily practice, we collected and analysed these in a patient cohort with regard to the recommendations of the national CUP guideline. Data of 161 patients diagnosed with CUP in 2014 or 2015 were extracted from the Netherlands Cancer Registry (NCR) and supplemented with diagnostic work-up information from patient files and analysed. Patients underwent an average of five imaging studies during the diagnostic phase (range 1-17). From the tests as recommended in the national guideline on CUP, a chest X-ray was most commonly performed (73%), whereas a PET-CT was done in one out of four patients (24%). Biopsies were taken in 86% of the study population, with Cytokeratin 7 being the most frequently tested histopathological marker (73%). Less than half of patients received therapy (42%). CUP patients undergo extensive diagnostic work-up. The performance status did not influence the extent of the diagnostic work-up in CUP patients, but it was an important factor for receiving treatment.

[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.

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.

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.

Metastatic Neuroendocrine Carcinoma of Unknown Origin Arising in the Femoral Nerve Sheath

BACKGROUND

Metastatic neuroendocrine carcinoma of unknown origin is a rare condition, usually presenting with lesions in the liver and/or lung. We present the first reported case of a metastatic neuroendocrine carcinoma of unknown origin arising in the femoral nerve sheath.

CASE DESCRIPTION

Magnetic resonance imaging demonstrated what was thought to be a schwannoma in the left femoral nerve sheath in the proximal femoral triangle, immediately inferior to the anterior inferior iliac spine. At the time of operation, the tumor capsule was invading surrounding tissue, as well as three trunks of the femoral nerve. The patient underwent a subtotal resection, preserving the integrity of the residual functioning femoral nerve trunks. Histologic evaluation determined that the tumor had features consistent with a metastatic neuroendocrine carcinoma of unknown primary origin. The patient recovered well postoperatively, and subsequent radiologic evaluation failed to demonstrate a potential primary site. Unfortunately, the patient re-presented with disease progression and was subsequently referred to palliative care.

CONCLUSIONS

We recommend that there is a definite role for surgery in the management of solitary neuroendocrine carcinoma of unknown origin.

Electronic Risk Assessment System as an Appropriate Tool for the Prevention of Cancer: a Qualitative Study

BACKGROUND

Decision making modalities for screening for many cancer conditions and different stages have become increasingly complex. Computer-based risk assessment systems facilitate scheduling and decision making and support the delivery of cancer screening services. The aim of this article was to survey electronic risk assessment system as an appropriate tool for the prevention of cancer.

MATERIALS AND METHODS

A qualitative design was used involving 21 face-to-face interviews. Interviewing involved asking questions and getting answers from exclusive managers of cancer screening. Of the participants 6 were female and 15 were male, and ages ranged from 32 to 78 years. The study was based on a grounded theory approach and the tool was a semi- structured interview.

RESULTS

Researchers studied 5 dimensions, comprising electronic guideline standards of colorectal cancer screening, work flow of clinical and genetic activities, pathways of colorectal cancer screening and functionality of computer based guidelines and barriers. Electronic guideline standards of colorectal cancer screening were described in the s3 categories of content standard, telecommunications and technical standards and nomenclature and classification standards. According to the participations' views, workflow and genetic pathways of colorectal cancer screening were identified.

CONCLUSIONS

The study demonstrated an effective role of computer-guided consultation for screening management. Electronic based systems facilitate real-time decision making during a clinical interaction. Electronic pathways have been applied for clinical and genetic decision support, workflow management, update recommendation and resource estimates. A suitable technical and clinical infrastructure is an integral part of clinical practice guidline of screening. As a conclusion, it is recommended to consider the necessity of architecture assessment and also integration standards.

Primary squamous cell carcinoma in the chest wall mimicking abscess

We report a case of squamous cell carcinoma (SCC) presenting a painful cystic mass which originated from the chest wall with bony destructions. The patient underwent complete excision with chest wall reconstruction. Although the imaging characteristics of chest wall tumor can be variable, SCC should be considered in differential diagnosis in the case of symptomatic cystic mass in elderly patients.