ABSTRACT
A case report<br>A 70-year-old male with small bowel adenocarcinoma involving retroperitoneal invasion had undergone chemotherapy after non-curative operation. However, this patient had to discontinue the first and second lines of chemotherapies within one month due to serious side effects of anti-cancer agents. Subsequently, the patient complained of severe low-back pain and there was evidence of local recurrence around the resected small intestine. Therefore, phototherapy was applied three times a week to relieve the low-back pain while the patient underwent the third line of chemotherapy. It was interesting to note that these combination therapies coincidentally ameliorated the various side effects caused by anti-cancer drugs. For one year during the third line of chemotherapy, the patient had to temporarily discontinue chemotherapy only two times when phototherapy was not available for one week due to consecutive national holidays in May and November. The quality of life of this patient was well maintained, and he only needed to be hospitalized for the last two months before he died.<br>Epidemiological studies have shown a high incidence of cancer in people less exposed to solar rays. The sunshine “vitamin” 1 alpha, 25-dihydroxy vitamin D<sub>3</sub> (1, 25(OH)<sub>2</sub>D<sub>3</sub>) is involved in these epidemiological studies based on the evidence that 1, 25(OH)<sub>2</sub>D<sub>3</sub> is an antiproliferative agent that may inhibit proliferation of cancer cells in vitro and development in animals. To elucidate the synergetic effect of phototherapy in combination with chemotherapy, we assayed serum levels of 1, 25(OH)<sub>2</sub>D<sub>3</sub> in this patient compared with those of end-stage cancer patients undergoing chemotherapy alone. Serum levels of 1, 25(OH)<sub>2</sub>D<sub>3</sub> in this patient after receiving the combination therapies were higher than those in other cancer patients treated with chemotherapy alone.<br>Our results indicate that phototherapy may be a good complementary therapy with chemotherapy for cancer patients.