[Surgical options in cancer of unknown primary (CUP)]

Local ablative treatment with surgery and/or radiotherapy in single-site and oligometastatic carcinoma of unknown primary

BACKGROUND

Single-site carcinoma of unknown primary (CUP) is recognised as a distinct favourable subtype in the European Society of Medical Oncology (ESMO) classification. There is broad consensus that these patients are candidates for local ablative treatment strategies with surgery and/or radiotherapy, but data on their outcomes are scarce.

PATIENTS AND METHODS

In this study, we have addressed the prospects of cure and prognostic factors in a retrospective cohort of 63 patients who were eligible for local treatment at our centre.

RESULTS

Median event-free (EFS) and overall survival (OS) were 15.6 months and 52.5 months, respectively. Of 61 patients who received local treatment, 20 (32.8%) remained event-free over a median follow-up of 28 months. Baseline clinical parameters including affected organ, number, volume and histology of metastases had no significant impact on prognosis, whereas deleterious TP53 mutations and DNA copy number loss emerged as independent adverse risk factors with respect to EFS. Surgical treatment was associated with improved OS as compared to radiation-based therapy.

CONCLUSION

Our study advocates to pursue localised treatment with surgery and/or radiotherapy whenever feasible and implies that genetic parameters might additionally determine the clinical course of single-site CUP patients.

CUP Syndrome-Metastatic Malignancy with Unknown Primary Tumor

BACKGROUND

2-4% of newly diagnosed cases of malignant disease involve cancer of unknown primary (CUP). This mixed entity is one of the 6 most common types of malignant disease in Germany. Highly refined treatment strategies can now be offered to patients with CUP.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed with an emphasis on articles from the past decade. The current guidelines and recommendations of specialty societies were also considered in the evaluation.

RESULTS

CUP most commonly manifests itself as metastases to the lymph nodes, lungs, liver, or bones. With the aid of imaging studies, including functional hybrid imaging and further medical examination, a primary tumor can be discovered in up to 40% of patients initially diagnosed with CUP. Immunohistochemistry guided by histomorphology often enables precise characterization of the lesion and can be supplemented, in selected cases, by molecular-genetic diagnostic evaluation. The most commonly detected types of primary tumor are cancers of the lung, pancreas, liver, and biliary system. For patients with local metastases, surgical resection or radiotherapy with curative intent is usually indicated, sometimes in the framework of a multimodal treatment concept. The median 2-year survival of patients with disseminated CUP is only 20%. For such patients, specific types of systemic therapy are recommended on the basis of the diagnostic characterization of the disease. Immune-modulatory antibodies can be effective, particularly in the treatment of CUP that has been characterized with biomarkers, but should still be considered experimental at present.

CONCLUSION

A combination of conventional and innovative diagnostic methods enables the provision of highly refined therapeutic strategies to patients with CUP who are undergoing treatment in interdisciplinary cancer centers.

Axillary lymph node metastases from unknown primary: A French multicentre study

PURPOSE

The aim of the study was to investigate the management and prognosis of axillary cancers from unknown primaries (CUPax).

METHODS

We included all patients with lesions described as axillary nodal metastases from an unknown primary referred to four French tertiary breast cancer centres between January 1988 and December 2012. The inclusion criteria comprised: no sign of primary breast cancer on clinical examination nor on imaging (mammography, ultrasonography and breast MRI) and no primary tumour identified elsewhere.

RESULTS

CUPax represented 1.8% of all metastatic axillary lymphadenopathies in our institutions. The overall survival rate was 71%, and 16.7% of patients had secondary inflammatory breast cancer signalling a posteriori that CUPax originated from the breast. Factors that favourably affected survival according to univariate analysis were: histological type of non specific adenocarcinoma (versus other types, p = 0.02), only one lymph node involved (versus several, p = 0.04), a normal CA153 serum-level (p = 0.02), no distant metastasis at initial assessment (p = 0.02), no secondary distant metastasis (p = 0.005) and radiotherapy to the ipsilateral breast/chest wall/lymph nodes (p = 0.04). On multivariate analysis including these factors, a histological type of non-specific adenocarcinoma (p = 0.03) and distant metastases (p = 0.03) were identified as independent factors affecting survival.

CONCLUSION

We believe that these results will shed light on current investigations and treatment of this rare entity.