For the first time, scientists have found evidence that pain is an independent marker for overall survival in recurrent ovarian cancer, with women with pain living for significantly less time after their diagnosis than those without pain.
The survival toll is particularly high for patients with pain despite receiving pain medication, who have seven months less to live than women without pain. The findings underscore the importance of effective pain management in ovarian cancer patients, the researchers said.
“Pain has not only an immense impact on quality of life and functioning but also on overall survival in ovarian cancer,” the investigators said. “Inadequate pain management was associated with decreased survival.”
The study, “The Prognostic and Predictive Role of Pain Before Systemic Chemotherapy in Recurrent Ovarian Cancer: an Individual Participant Data Meta-Analysis of the North-Eastern German Society of Gynecological Oncology (NOGGO) of 1226 Patients,” was published in the journal Supportive Care in Cancer.
Pain is a very common symptom among cancer patients and survivors, and it significantly affects quality of life and mental health. However, despite guidelines by multiple organizations for pain management, optimal pain medication remains a challenge.
On top of that, physicians tend to underestimate pain in cancer patients, particularly in women, the study found.
The researchers sought to determine if pain influences the survival of women with ovarian cancer, and if so, whether pain medications reduce the toll it takes on patients’ lives. To do so, the team of German scientists retrospectively examined data from 1,226 patients who participated in three clinical trials (NCT00312988, NCT00437307, and NCT01047891), all held in Berlin.
The trials, conducted by the North-Eastern German Society of Gynecological Oncology (NOGGO), compared the efficacy of different treatments for recurrent ovarian cancer.
The majority of patients (84.7%) had locally advanced or metastatic disease and were enrolled during their first recurrence (83%).
Data on pain was available for 952 women, and more than one-third (36.6%) reported moderate-to-severe pain. A total of 31% were taking non-opioid medication, while 16% had been prescribed opioids.
There were no differences between patients with or without pain in terms of disease stage, number of recurrences, blood toxicity, or response to platinum-based chemotherapy. The researchers also noted no difference between chemotherapy regimens, and no association between pain and progression-free survival (the length of time a patient lives without the disease getting worse).
However, women with pain had a worse functional status and had received less cycles of chemotherapy than patients without pain. Despite that, these women did not discontinue chemotherapy more often than those without pain.
As expected, quality of life was significantly diminished by pain. Fatigue, nausea and vomiting, sleeping disorders, and abdominal symptoms such as loss of appetite, diarrhea, and constipation, were all more frequently found in women with pain.
Researchers then found that the median overall survival of patients without pain was 22 months, but it decreased to 18.2 months in women with pain.
In addition, pain management and the women’s response to it influenced survival as well. The results showed that the median overall survival of patients with pain who received sufficient pain medication was 19.6 months. However, it decreased to 18.5 months in women without sufficient pain medicine. Patients with pain despite receiving pain medication had the lowest overall survival: 15 months.
“We could show that ovarian cancer patients with moderate to severe pain have a decreased survival compared with patients without pain. Thus, sufficient pain medication is paramount not only to improve quality of life but also to improve survival,” the investigators said.
The team acknowledged some limitations to their study, such as its retrospective nature. They also noted that “data were derived from phase II/III trials which were not powered for this individual patient data meta-analysis.”
However, according to the researchers, “this study underlines the urgent need for effective pain management for both quality of life and overall survival in patients with recurrent ovarian cancer. Patients shall therefore receive best supportive care as early as possible. This should be further investigated in prospective trials.”