New City Osaki Clinic homepage > Treatment outcomes and case reports > Pancreatic cancer, case of pancreatic cancer 1
This patient, who is in their 80s, first underwent examination because of abdominal pain and diarrhea. A tumor of 2.5 cm in diameter was found in pancreatic head. The patient was diagnosed with advanced pancreatic cancer of stage 4a involving blood vessels. Fortunately, there was no distant metastasis, but surgeries were impossible due to old age. This patient thus requested highly active NK (natural killer) cell therapy at the New City Osaki Clinic.
In cooperation with the patient’s regular hospital, highly active NK cell therapy was started in combination with a low dose treatment in which 40 mg/day of an oral anticancer agent, TS-1, was administered for one week and the administration was suspended for one week. TS-1 is an anticancer agent, but did not cause any problematic side effects other than mild discomfort in stomach because it was used at a low dose, which typically has minor adverse impact.
In immune cell therapy, the first few times of administration were given at a two-week interval, and then the interval was extended to four weeks and later to six weeks. As the therapy was continued, the patient regained their appetite and came to be able to lead the life not different from the daily life before the onset of cancer. It has already been over one and a half years since the diagnosed of advanced pancreatic cancer.
Figure 1 shows the change in a tumor marker after the start of treatment for pancreatic cancer. CA19-9 was decreased two months after the start and maintained around 1000 after that. In regular CT scan, neither increase nor decrease in the size of the cancer has been observed and no metastasis has been detected. The cancer almost stopped progressing and the condition without progression has been maintained.
In the initial six times of administration, 82 billion active lymphocytes (on average, 13.7 billion per dosing) were given to this patient. NK cells accounted for 60% of these lymphocytes. Thus, the mean number of NK cells administered per dosing was 8.2 billion and the remaining cells were activated T cells (mainly, cytotoxic T cells). When such a large amount of NK cells and activated T cells are administered to the body, the lymphocytes in the blood circulating in the body are also changed.
First, the lymphocyte count was almost doubled compared with 1000/μl before the treatment (Figure 2).
When we examined the increased lymphocytes in detail, the proportion of NK cells increased from 16.9% to 36.3% and the NK activity was also enhanced from 36% to 57%. At the same time, the proportion of NKG2D-positive lymphocytes increased from 39.9% to 61.5% (Figure 3).
This patient had a certain level of immunity before the start of treatment and their immunity was enhanced by the treatment.
We consider that concomitant use of a small amount of TS-1 increased the sensitivity of cancer cells to immunity (making cancer cells susceptible to the attack by immune cells), that the administration of a large amount of highly active NK cells and activated T cells in the above condition provided the strong troop that can directly attack cancer cells, and that subsequent increase in the number and activity of NK cells in blood resulted in stronger immunity of the body. From now, it is necessary to observe the patient’s condition to speculate whether or not such good conditions last over time. However, pancreatic cancer, which was considered in the past to progress rapidly, appears to be in a “dormant state” in this patient at present.
Progression of cancer is generally thought to be slower in older patients. In a study comparing the outcome of treatment in patients in their 60s and those in their 80s, however, the outcome of those in 60s was reported to be better. Because patients in their 80s are physically weak and their immune systems are compromised, not only surgeries but also the use of some anticancer agents is considered to be difficult.
Thus, even for old patients with difficult-to-treat pancreatic cancer, it is possible to provide treatment that enables them to survive with as few burdens as possible by combining a very small amount of anticancer agents that does not lead to side effects and highly active NK cell therapy.