This retrospective, single-center study shows that assessment of the residual fatty tissue does not lead to the finding of more positive lymph nodes, even though the extended pathological assessment resulted in a 29% higher lymph node count. As might be expected, extra lymph nodes discovered in residual fat tended to be very small. It should also be considered that it may be possible in some cases that the ‘extra’ lymph nodes were actually fragments of the palpable lymph nodes that had been left behind after conventional dissection.

The median number of lymph nodes resulting from conventional pathology dissection in our study was 21. This corresponds with what is described in the literature; a mean of 21 to 32 lymph nodes is reported in various studies [7,8,9,10].

Both approaches to pathology dissection have their benefits and disadvantages. Using the standard procedure, very small lymph nodes are not visible by macroscopic inspection, resulting in a lower lymph node count [1]. Using the extended approach, smaller lymph nodes are identified, usually resulting in a higher lymph node count, and possibly representing a more accurate reflection of the exact number of lymph nodes present in the specimen. The extended approach is likely to be less influenced by the individual pathologist performing the dissection [11], making it easier to compare different clinics, surgeons, and even different treatment strategies. However, this approach is more time-consuming and costly [1]. The median cost of the extra assessment of the residual fatty tissue was estimated as 264 euros. This may pale into insignificance compared to the cost of the entire treatment, but it is important to be critical where the yield seems minimal.

This is a retrospective study with several limitations. First, this is a single-center study, and the results may not be generalizable, owing to differences in population and pathological protocols. There was no revision of the pathology; however, the pathology reports are standard and are issued by pathologists experienced in the subspecialty. Although we included 85 patients, our study population may be too small to find an undetected positive node in the residual fatty tissue. We consider it to be a strength that we studied two different tumor types and that two groups of surgeons (gynecologists and urologists) performed the operations. There was no recall bias, outliers were checked and validated. Double entry of data was performed.

The present study indicates that the current pathology practice (enclosing only those lymph nodes detected by sight and/or palpation) is adequate. There appears to be no clinical relevance to studying residual fatty tissue; no extra positive lymph nodes were found, and there was therefore no effect on further treatment in both cervical and bladder cancer.