Trimming in of a spleen with a mass
We’ve provided guidelines and sampling tips to significantly improve their diagnostic accuracy for haemangiosarcoma in splenic masses, leading to better patient outcomes.
Larger splenic masses, in particular haemangiosarcomas, are prone to develop extensive haemorrhage and necrosis to a point, where neoplastic tissue is to a vast extent replaced by a haematoma.
Because of this, viable and diagnostic neoplastic tissue may be very difficult to find in the histologic sections.
The likelihood of detecting a haemangiosarcoma in the spleen compared to the number of sections examined has been evaluated in a paper by Herman et al.
According to this paper, if only 1 or 2 sections of a splenic mass are examined, the likelihood of missing a haemangiosarcoma is 32% and 17% respectively.
If 5 sections from a splenic mass are examined, the likelihood of detecting haemangiosarcoma increases to 95%.
Based on these results, by default, we always trim in 5 sections of any larger splenic mass, as well as one section of a macroscopically normal area of spleen.
It is very important that the sections are taken from the transition area of the mass into the spleen, as the probability of finding viable neoplastic tissue in these areas is higher. If the subcapsular haematoma is sampled, frequently, no neoplastic tissue is histologically detected in the sections.
Statistically, increasing the number of sections of a mass examined, increases the likelihood of detecting haemangiosarcoma only marginally, e.g. 10 sections are predicted to detect haemangiosarcoma in 99% of cases. However, if histologically in the 5 sections of the mass that we routinely examine, no neoplastic tissue is seen and no other convincing cause for the mass lesion is found, then we request additional sections of the mass to further rule out an underlying neoplasm.
If you send a whole spleen for histology, cutting the surface of larger masses, as well as the surface of the spleen can help with fixation, as the thick capsule and high blood content of the spleen often cause poor fixation.
We understand that sending a whole spleen can be cumbersome, especially if containers of adequate size to fully immerse the spleen in sufficient amounts of formalin are not at hand. Consider cutting off the part of the spleen with the mass and fixing and submitting only this part. Alternatively, portions of a mass can be submitted, however, if you choose to do this, please follow the sampling protocol that we apply in our lab: sample at least 5 different regions of the mass, where it transitions into normal spleen and avoid sampling of the subcapsular haematoma.
For further information on our histopathology services, please contact us by emailing [email protected] or by calling 0117 951 1283.