exploratory surgery, manual and instrumental means of investigating an area of the body suspected of disease when a specific diagnosis is not possible through noninvasive or simple biopsy techniques. If the lesion is in the abdomen, exploratory surgery involves a laparotomy, or incision into the abdomen to observe the lesion. If possible, a biopsy sample is removed. In some cases a lesion may be inoperable because of its location or attachment to vital structures from which it cannot be separated.