Submandibuler growth with bilateral multiple lung nodules , is it malignancy case?

Possible: The diagnosis of malignancy is definitive only on biopsy. However, there are suspicious patterns and presentations. Yours may be one but it's hard to tell without much information.

Tissue needed: Not necessarily. Is worrisome. But, there are non-cancer, inflammatory conditions/diseases that can present. One example, systemic sarcoidosis can present like this. Don't give up hope.

Need more info...: About your symptoms and the imaging. Lung nodules and growth within or next to the submandibular gland raise suspicion for cancer, but need to put all of the data together. Will probably need to have a biopsy to get tissue to examine under the microscope - that will allow an exact diagnosis and plan of treatment.