Investigation of unprovoked venous thromboembolism: a case for a tempered approach?

CT imaging for occult malignancy in patients with unprovoked venous thromboembolism (VTE) in a tertiary centre: is it worthwhile?

BACKGROUND

Investigating patients with unprovoked venous thromboembolism (uVTE) for occult malignancy can prove a diagnostic dilemma and imaging is often used extensively in this patient group.

AIMS

The primary objective of this study was to determine the incidence of malignancy on CT and other imaging over a 10-year period. A secondary objective was to evaluate the role of laboratory and other non-imaging tests performed.

METHODS

A retrospective key word search of our hospital's imaging system was performed to identify patients with unprovoked DVT/PE over the last 10 years. All imaging, histology, endoscopy, laboratory tests, and clinical follow-up over 2 years were analysed. Patients with provoked VTE were excluded.

RESULTS

150 patients had uVTE. 9 patients were diagnosed with occult malignancy by different investigations on index hospital admission (3 patients) or subsequently on clinical follow-up (6 patients). Mean age of patients was 62 years. 116 patients had CT body imaging. The incidence of malignancy diagnosed by initial CT imaging was 1.7% with a sensitivity of 22%, specificity 87%, and PPV 12.5%. Overall incidence of malignancy identified by imaging alone during the index hospital admission was 2%. Total incidence of malignancy including index admission and follow-up was 6%. Median time to cancer diagnosis was 12 months.

CONCLUSION

CT imaging had a low yield for diagnosing malignancy. Extensive imaging strategies increase cost and radiation exposure without improving mortality. Clinical follow-up, history taking, and physical examination guiding appropriate investigations remain the best tool for unmasking occult malignancy in patients with uVTE.

Unprovoked venous thromboembolism in women over 40: is screening for occult malignancy with mammography and abdominopelvic CT of benefit?

AIM

To determine imaging and pathological outcomes in cases of unprovoked venous thromboembolism (VTE) referred for mammogram. A secondary objective was to elucidate outcomes of abdominopelvic computed tomography (CT) imaging performed in this cohort.

MATERIALS AND METHODS

A retrospective review of mammograms performed in cases of unprovoked VTE was undertaken from January 2016 to September 2019. Patient notes and imaging were reviewed to establish patient demographics, additional imaging required, biopsies performed, pathology findings, and eventual outcomes. Cases were reviewed to determine if concurrent CT abdomen/pelvis was performed to screen for malignancy. Outcomes of CT were recorded.

RESULTS

One hundred and thirty-nine women attended for screening mammogram following unprovoked VTE during the study period. Mean patient age was 68 years (range 42-89 years). Fourteen women (10%) were recalled for further breast imaging, with two cases of confirmed malignancy (1.4%). Of the 139 women, 118 also underwent CT imaging, with 18 patients (15%) recalled for further investigations. Two (1.7%) cases of malignancy (lung and ovarian) were identified.

CONCLUSION

A low cancer detection rate was demonstrated in women undergoing mammography or CT following unprovoked VTE. In addition, the high number of false-positive findings and need for additional investigations questions the value of screening in this setting. Based on these findings, Cambridge Breast Unit has ceased mammographic and abdominopelvic CT imaging in women with unprovoked VTE, anticipating the newly updated National Institute for Health and Care Excellence (NICE) guidelines.