The haemorrhage exclusion sign can be a useful MRI finding following prostate biopsy.
The normal prostate produces high concentrations of citrate, which among other properties, acts as an anticoagulant 1. As tumour cells are dysfunctional, they will produce lower levels of citrate than the surrounding normal prostate and should bleed less.
Post-biopsy haemorrhage is detectable on multiparametric prostate MRI, particularly in the peripheral zone 2, as hyperintense areas on T1W sequences, due to the paramagnetic effect of methaemoglobin.
The abnormal prostate tissue will appear darker on T1W (with corresponding low T2W signal and diffusion restriction) and will be outlined by the haemorrhage in the adjacent normal prostate, hence can help identify or delineate lesions 1,2.
Treatment and prognosis
Alone, the positive predictive value (PPV) of this haemorrhage exclusion sign is about 50%, but with consideration of other features on other sequences, this can approach 95% for prostate cancer 3. This can be especially useful in the post-biopsy state, where post-biopsy changes are considered to reduce the diagnostic yield of MRI.
- 1. Rosenkrantz AB, Taneja SS. Radiologist, be aware: ten pitfalls that confound the interpretation of multiparametric prostate MRI. AJR. American journal of roentgenology. 202 (1): 109-20. doi:10.2214/AJR.13.10699 - Pubmed
- 2. Tamada T, Sone T, Jo Y, Yamamoto A, Yamashita T, Egashira N, Imai S, Fukunaga M. Prostate cancer: relationships between postbiopsy hemorrhage and tumor detectability at MR diagnosis. Radiology. 248 (2): 531-9. doi:10.1148/radiol.2482070157 - Pubmed
- 3. Barrett T, Vargas HA, Akin O, Goldman DA, Hricak H. Value of the hemorrhage exclusion sign on T1-weighted prostate MR images for the detection of prostate cancer. Radiology. 263 (3): 751-7. doi:10.1148/radiol.12112100 - Pubmed