Years ago, whenever Dad had tinned fish on toast, he would mix Lea & Perrins Worcestershire sauce into any particular fish mix. Before I left my accommodation a few weeks ago, I'd re-discovered Worcestershire by mixing it in with tinned fish to then put in salad.
The primary purpose of Worcestershire sauce is to enhance the flavour of any food it is mixed into; in some cases, such as tinned tuna, it can be used to moisten a particular food. It is especially effective when adding to casseroles and some pies.
I re-discovered it because I had some tins of tuna to eat but the tuna was all dry; as such, I remembered what Dad used to put in his tinned fish.