Aggravation of Hemorrhoids in Patients With Cervical Cancer Undergoing Radiotherapy: A Nationwide Population-based Study

Discussion

This study was undertaken to determine whether RT aggravates hemorrhoids in patients with cervical cancer. We found that RT significantly increased rates of hemorrhoid aggravation and anal bleeding in this patient population. The anorectal side-effects of pelvic irradiation are classified as radiation-induced proctitis (10), and the effect of irradiation on hemorrhoids is often neglected. As a result, few studies have addressed the relationship between RT and hemorrhoids (5, 8, 9). The symptoms of acute proctitis are diarrhea and tenesmus and those of chronic proctitis are bleeding and painful defecation (10). However, if hemorrhoids are exacerbated, bleeding and pain appear early in the RT period (5, 6). Therefore, the differential diagnosis of hemorrhoid aggravation and radiation-induced proctitis is essential to ensure that proper treatment choices are made, and it should be determined whether acute anal symptoms are due to hemorrhoid aggravation or lower rectal wall problems. If it is decided that symptoms are due to hemorrhoid aggravation, clinical management involving sitz baths and dietary changes is necessary (11, 12). Although acute anal symptoms are not considered severe, once exacerbated, they may be painful for long periods and result in poor tolerance to RT. For these reasons, patients with hemorrhoids need to be managed at RT initiation.

It is known that tolerable dose for anal canal and rectum is around 50-60 Gy (7, 13), but it has been reported that hemorrhoid aggravation occurs at doses around 30 Gy (5), which indicates radiation-induced proctitis and hemorrhoid aggravation have different tolerance doses. When whole-pelvic RT is performed at total doses not exceeding 50 Gy, asymptomatic hemorrhoids are often ignored clinically or addressed with empirical anal blocks, although recent advances in RT techniques enable more sophisticated types of RT, such as IMRT, to be used. 3D-CRT using box techniques has been widely used for postoperative RT in cervical cancer. Several recent research studies have used pelvic IMRT to reduce radiation exposure to normal tissues such as bladder, rectum, and small bowel (14-16). However, the anus is infrequently considered an organ at risk. In this study, we compared the effects of 3D-CRT and IMRT on hemorrhoid aggravation and bleeding frequency, but no significant differences were observed between the two modalities. We recommend that more detailed analysis be conducted to investigate the effects of RT techniques, total doses, and fractioned doses. Unfortunately, since this study was conducted using insurance claim data, detailed data on RT schedules were not obtained.

Many factors cause hemorrhoids such as age, low-fiber diet, pregnancy, weight, underlying diseases, and bowel habits (12, 17, 18). To identify the effect of RT on hemorrhoids, we analyzed rates of anal bleeding and newly diagnosed hemorrhoids within one year after RT. We found that the ORs of both were significantly higher in the DRT group than in the surgical group. It is reasonable that asymptomatic hemorrhoids were worsened by RT, rather than the occurrence of new hemorrhoids. Although the number of newly diagnosed hemorrhoid cases was only 291 among 5,919 patients, this study was based on insurance claim data, and thus, only hemorrhoids that required active treatment were included. There is a study showing that the location of anal verge and anal canal has a large deviation for each patient (8). Patients have different anatomical structures and different underlying diseases. Therefore, different treatments are required for each patient. In particular, patients with hemorrhoids can be affected by small amounts of radiation, and thus, careful attention is needed from the treatment planning stage. For example, if a patient with hemorrhoid and diabetes receives pelvic irradiation, the anal canal dose should be reduced and strict diabetes control is required. Diet or medication may be modified to prevent constipation.

As this study was based on insurance claim codes, specific information about RT schedules (e.g., on planning techniques and radiation doses) and detailed information on hemorrhoid and toxicity severities were not available. However, the study was performed using the data of a large number of patients, and thus, we believe that our findings are statistically meaningful. Notably, the study shows RT worsens anal bleeding and hemorrhoids. In particular, patients with diabetes and those that undergo combined chemotherapy are at an increased risk. If patients with hemorrhoids receive pelvic RT, careful management is required to prevent hemorrhoid aggravation. We recommend that additional studies be performed to determine the effects of different RT schedules and techniques on hemorrhoid aggravation.