My husky has a chest lump, drinks a lot, and barely urinates. Serious?

the two problems may be related and personally I would give priority to the lump at this stage.
Although a picture of it would help to determine the underlying cause more specifically, generally speaking this kind of lump/growth needs to be ideally assessed by your veterinarian to have a definitive and specific answer. Usually there are two ways your vet can do that a part from examining it directly during physical examination. A biopsy can be taken under local or general anesthetic, otherwise a smaller sample through a fine needle can be aspirated (this technique is called FNA= fine needle aspiration).
Differentials include skin cysts, infections, benign or more sinister type of tumors.
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