A Senior Medical Student Taking a Surgical Examination Was Asked $(10 \mathrm{~cm})$

A senior medical student taking a surgical examination was asked to look at a 55-year-old man. On examination of the abdomen, he found a hard, fixed mass in the midline, about 4 in. $(10 \mathrm{~cm})$ in diameter, lying on the transpyloric plane. On questioning, the patient said that he had recently lost $20 \mathrm{lb}$ and had a poor appetite. The student told the examiner that the patient was suffering from a carcinoma of the stomach and should have an immediate gastrectomy. The examiner then asked the student if he had examined the patient's scrotum, and the student admitted he had not. On examination, the scrotum was found to contain a large, hard mass on the right side that was not tethered to the skin. The inguinal lymph nodes on the right side were normal. Explain the connection between the abdominal swelling and the scrotal swelling. Why were the inguinal lymph nodes normal?