Hyperbaric oxygen therapy as a complementary treatment for radiation proctitis: Useless or useful? – A literature review

Table 1 Classification of stages/grades of radiation proctitis

Ref.	Stages/grades	Description
Sherman[27], 1954	I-IV	Based on endoscopic findings: I: (a) Localised erythema and telangiectasia, friable mucosa with easy bleeding: no ulceration or stricture formation, and (b) More diffuse erythema along with periproctitis, marked pain, and sensitivity; II: Presence of ulceration with a greyish tenacious slough, usually involving the anterior rectal wall, and proctitis with grade I lesions; III: Presence of rectovaginal fistulae or bowel perforation and varying degrees of proctitis with ulceration; IV: Presence of rectovaginal fistulae or bowel perforation and varying degrees of proctitis with ulceration.
Dean and Taylor[28], 1960	I-III	Based on clinical and endoscopic findings: I: Symptoms: Rectal bleeding, tenesmus, sphincter instability, mucoid discharge; endoscopic findings of vascular congestion, friability of the mucosa, mucosal thickening, mucoid discharge; II: Same symptoms as before; endoscopic findings of ulcerations, underlying thrombosis of the small vessels; III: Same symptoms as before plus perineal sepsis, incontinence, diarrhoea, perianal purulent discharge; endoscopic findings of necrosis, fistulae, strictures.
Gilinsky et al[29], 1983	Normal; Mild; Moderate; Severe	Based on endoscopic findings: Score 0: Normal mucosa; Score 3: Erythema and/or telangiectasia, oedema, thickening, pallor of mucosa; Score 6: Friability; Score 9: Ulceration and/or necrosis.
Langberg et al[30], 1992	1-3	Based on histopathologic findings: Thickening of serosa: (1) Slight thickening of serosa, hyperplasia of peritoneal mesothelium; and (2) Marked thickening of serosa; and (3) Extreme thickening and fibrosis serosa. Mucosal alterations: (1) Small superficial ulcerations; and (2) Ulcerations involving more than half of the intestinal circumference. Epithelial atypia: (1) Abnormally oriented crypts; (2) Irregular crypt regeneration with atypical epithelial cells; and (3) Adenocarcinoma. Vascular sclerosis: (1) Slight double normal thickness, broadened and hyalinised collagen fibres; (2) Submucosa three to four times normal thickness, abnormal collagen fibres; and (3) Massive fibrosis including muscularis. Lymph congestion: (1) Dilated lymph vessels or cystic collections of lymph. Ileitis cystica profunda: (1) Submucosal glandular inclusions; (2) Submucosal cysts with polypoid elevation of the mucosa; and (3) Large cysts extending into the muscularis.
Chutkan et al[31], 1997	0-4	Based on clinical findings: 0: No haemorrhage; 1: Blood on toilet paper or mixed with faeces; 2: Drops of blood in the toilet; 3: Severe haemorrhage with expulsion of clots; 4: Haemorrhage that requires transfusion.
Wachter et al[32], 2000. Vienna Rectoscopy Score	0-5	Based on endoscopic findings: Score 0: Congested mucosa (grade 1); Score 1: Congested mucosa (grade 2), telangiectasia (grade 1); Score 2: Congested mucosa (grade 3), telangiectasia (grade 2); Score 3: Congested mucosa (any grade), telangiectasia (grade 3), ulceration (grade 1); Score 4: Congested mucosa (any grade), telangiectasia (any grade), ulceration (grade 2), stricture (grade 1); Score 5: Congested mucosa (any grade), telangiectasia (any grade), ulceration (grade 3), stricture (grade 2), necrosis (any grade).
Zinicola et al[33], 2003. Bleeding Scale for Radiation-Induced Haemorrhagic Proctitis	0-4	Based on clinical findings: 0: No bleeding; 1: Intermittent bleeding (once weekly or less); 2: Persistent bleeding (twice or more weekly); 3: Daily bleeding or anaemia; 4: Require blood transfusion.
Chi et al[34], 2005. RTD grading scale	0-3	Based on RTD endoscopic findings: 0: Normal mucosa; 1: < 10 telangiectasias; 2: > 10 telangiectasias; 3: Confluent lesions, active bleeding or friable mucosa.
Ehrenpreis et al[35], 2005. Radiation Proctopathy System Assessment Scale (RPSAS)	1-5	Based on clinical findings: Diarrhoea. Urgency. Rectal pain. Tenesmus. Rectal bleeding. Faecal incontinence. Severity: 1: No problem. 2: Mild problem–can be ignored when you do not think about it. 3: Moderate problem–cannot be ignored; no effect on ADL. 4: Severe problem–influences your concentration on ADL. 5: Very severe problem–markedly influences your ADL and/or requires rest. Frequency: 1: Monthly; 2: Weekly; 3: Several times per week; 4: Daily; 5: Throughout the day.
Cox et al[36], 1995. Late Radiation Morbidity Scoring Criteria Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer	0-5. Late (> 3 mo)	Based on clinical and imaging findings: 0: No changes; 1: Mild diarrhoea, mild cramping, bowel movement 5 times daily, slight rectal discharge or bleeding; 2: Moderate diarrhoea or colic, bowel movement > 5 times daily, excessive rectal mucus or intermittent bleeding; 3: Obstruction or bleeding requiring surgery; 4: Necrosis, perforation, or fistulae; 5: Death related to adverse event.
NCI CTCAE version 5.0[37], 2017	1-5	Based on clinical findings: 1: Mild adverse event; rectal discomfort, intervention not indicated; 2: Moderate adverse event; rectal discomfort, passing blood or mucus, medical intervention indicated, limiting instrumental ADL; 3: Severe and undesirable adverse event, faecal urgency or stool incontinence, limiting self-care ADL; 4: Life-threatening or disabling adverse event, urgent intervention needed; 5: Death related to adverse event.

ADL: Activities of daily living; RTD: Rectal telangiectasia density.