Transanal Total Mesorectal Excision Versus Robotic Total Mesorectal Excision

Conversion is defined as an abdominal incision larger than necessary for specimen retrieval for the abdominal phase of transanal total mesorectal excision (TME) and robotic TME; for the transanal phase of transanal TME conversion is defined as failure to complete a 'down-to-up' TME transanally, and the majority of the TME has to be completed using the abdominal approach.

From 0 which implies no pain at all, to 100 which implies the worst pain imaginable, on the first 3 postoperative days.

Surgical complications are classified according to the Clavien-Dindo classification.

IPSS is based on the answers to seven questions concerning urinary symptoms and one question concerning quality of life. Each question concerning urinary symptoms allows the patient to choose one out of six answers indicating increasing severity of the particular symptom. The answers are assigned points from 0 to 5. The total score can therefore range from 0 to 35 (asymptomatic to very symptomatic).

IIEF-5 is an abridged five-item version of the 15-item International Index of Erectile Function (IIEF) which is used to diagnose the presence and severity of erectile dysfunction. This questionnaire consists of only five questions and each IIEF-5 item is scored on a five-point ordinal scale where lower values represent poorer sexual function. Thus, a response of 0 for a question is considered the least functional, whereas a response of 5 is considered the most functional. The possible scores for the IIEF-5 range from 1 to 25 (one question has scores of 1-5), and a score above 21 is considered as normal erectile function and at or below this cutoff, erectile dysfunction.

The Cleveland Clinic Incontinence Score or Wexner's Score is the most common score used to determine the severity of incontinence before and after surgery for anal incontinence. The scoring system takes into account the type and frequency of incontinence, and the extent to which it alters the patient's life. It consists of five questions to assess the degree of incontinence (solid, liquid, gas, wears pad, lifestyle alteration). The frequency of each type of incontinence is rated on a scale ranging from 0 (never) to 4 (always or to once a day) so that the sum of the frequencies add up to a total score that may range from 0 to 20. Higher scores indicate higher levels of incontinence.

The Short Form 36 (SF-36) Health Survey is a 36-item, patient-reported survey of patient health. It consists of eight scaled scores, which are the weighted sums of the questions in their section. The eight sections are: vitality, physical functioning, bodily pain, general health perceptions, physical role functioning, emotional role functioning, social role functioning, and mental health. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The lower the score the more disability. The higher the score the less disability i.e., a score of zero is equivalent to maximum disability and a score of 100 is equivalent to no disability.

EORTC QLQ-C30 is a generic questionnaire for assessment of quality of life (QoL) in cancer patients. It includes 30 items, 24 of which are combined to form a global QoL scale, five functional scales (physical, role, emotional, cognitive, and social), and three symptom scales (fatigue, nausea/vomiting, and pain). The other six single items evaluate dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties. All questionnaires responses and scores will be linearly transformed to a 0-100 scale. A higher score on the global QoL and functional scales represents a higher level of QoL and functioning, whereas a higher score on the symptom scales/items represents a higher degree of symptoms or dysfunction.

EORTC QLQ-CR38 is a specific questionnaire module specifically designed for assessment of quality of life (QoL) in patients with colorectal cancer. It consists of 38 items covering symptoms and side effects related to different colorectal cancer treatment modalities. The module contains four functional scales (body image, sexual functioning, sexual enjoyment, and future perspective) and eight symptom scales/items (micturition problems, chemotherapy side effects, gastrointestinal tract symptoms, male sexual problems, female sexual problems, defecation problems, stoma-related problems, and weight loss). All questionnaires responses and scores will be linearly transformed to a 0-100 scale. A higher score on the global QoL and functional scales represents a higher level of QoL and functioning, whereas a higher score on the symptom scales/items represents a higher degree of symptoms or dysfunction.