A Phase 3 interventional study of Intensity-Modulated Radiotherapy (IMRT) and Capecitabine in Anal Squamous Cell Carcinoma, Limited-stage, sponsored by Cancer Institute and Hospital, Chinese Academy of Medical Sciences. Recruiting at 2 sites in China. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-07-09.
Sponsored by Cancer Institute and Hospital, Chinese Academy of Medical Sciences · Phase 3, Interventional, and Treatment
This is a prospective, multicenter, open-label, phase III randomized controlled clinical trial designed to evaluate the efficacy and safety of replacing the traditional chemotherapeutic drug mitomycin with the PD-1 inhibitor sintilimab in definitive chemoradiotherapy for limited-stage anal squamous cell carcinoma. The study plans to enroll 350 previously untreated patients with limited-stage anal squamous cell carcinoma and randomize them in a 1:1 ratio into two groups: the control group will receive the current standard treatment, namely intensity-modulated radiotherapy (IMRT) concurrent with capecitabine and mitomycin; the experimental group will receive an innovative "immunotherapy replacement" regimen, namely IMRT of the same technique concurrent with capecitabine and sintilimab. The study adopts a dual primary endpoint design, aiming to verify that the experimental group is non-inferior to the control group in the clinical complete response rate at 6 months after radiotherapy, and is significantly superior to the control group in the incidence of grade 3 or higher treatment-related acute toxicities.
297 studies on the registry are indexed under Anus Neoplasms; 74 are open to participants now.
This study's planned enrollment of 350 is above the median of 66 across 211 interventional studies indexed under Anus Neoplasms.
Browse Anus Neoplasms studies →Cancer Institute and Hospital, Chinese Academy of Medical Sciences is the lead sponsor of 393 studies on the registry; 280 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CD4 count
The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
PD-1, PD-L1 and checkpoint inhibitors
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
COPD
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Standard definitive chemoradiotherapy for limited-stage anal squamous cell carcinoma: Intensity-modulated radiotherapy (IMRT) concurrent with capecitabine and mitomycin.
Radiation: Intensity-Modulated Radiotherapy (IMRT) · Drug: Capecitabine · Drug: Mitomycin (MMC)
Innovative immunotherapy replacement regimen: Intensity-modulated radiotherapy (IMRT) concurrent with capecitabine and sintilimab (PD-1 inhibitor) for limited-stage anal squamous cell carcinoma.
Radiation: Intensity-Modulated Radiotherapy (IMRT) · Drug: Capecitabine · Biological: Sintilimab
Intensity-modulated radiotherapy (IMRT) will be administered: * Primary tumor: 1.8 Gy per fraction, 28-30 fractions, total dose 50.4-54 Gy; * Metastatic lymph nodes: 1.68-1.8 Gy per fraction, 30 fractions, total dose 50.4-54 Gy; * Elective nodal regions: 1.5 Gy per fraction, 28-30 fractions, total dose 42-45 Gy; Treatment will be administered 5 days per week, concurrently with systemic chemotherapy (capecitabine ± mitomycin/sintilimab), in accordance with institutional standard practice for anal squamous cell carcinoma.
Oral capecitabine at 825 mg/m² twice daily on days of radiotherapy, concurrent with IMRT, as part of the chemoradiotherapy backbone for both study arms.
Intravenous sintilimab at 200 mg every 3 weeks, administered concurrently with capecitabine and IMRT to the experimental arm as an immunotherapy replacement for mitomycin.
Intravenous mitomycin at 10 mg/m² as a single bolus dose on day 1 of radiotherapy, administered only to the control arm as part of the standard chemoradiotherapy regimen.
Clinical Complete Response (cCR) Rate
cCR is defined as the simultaneous fulfillment of the following criteria: ① Digital rectal examination (DRE): no palpable nodule or ulcer, with only a smooth scar or fibrosis remaining; ② Anoscopy: no macroscopic evidence of residual tumor, with histopathological biopsy required for confirmation if suspicious lesions are present; ③ PET/CT: no residual tumor or new metastatic disease, or no evidence of residual tumor on contrast-enhanced CT or MRI if PET/CT is unavailable.
Time frame: 6 months after radiotherapy
Grade ≥3 acute TRAEs
According to the CTCAE version 5.0 criteria, non-hematologic toxicities of grade ≥3 (including cutaneous and mucosal reactions, gastrointestinal reactions, and genitourinary reactions), hematologic toxicities (including leukopenia, neutropenia, thrombocytopenia, and anemia, excluding lymphopenia), and immune-related adverse events occurring from the start of local treatment to 90 days after the completion of treatment will be evaluated. The investigator will determine whether these events are treatment-related adverse events.
Time frame: From the start of local treatment to 90 days after the completion of treatment
AEs rate
The incidence and severity of all-grade adverse events during treatment and post-treatment will be evaluated according to CTCAE version 5.0, and investigators will determine whether they are immune-related adverse events (irAEs).
Time frame: 2 years after randomization
Quality of life (QoL) in cancer patients
Quality of life in cancer patients will be evaluated using the European Organisation for Treatment and Research of Cancer (EORTC) Quality of Life Questionnaires QLQ-C30. The scoring and interpretation of the QLQ-C30 scales were performed according to the EORTC guidelines. Each item is scored from 0 to 100, with higher scores indicating better functioning on the functional scales/items and more severe symptoms on the symptom scales/items.
Time frame: Baseline, 3 days after completion of radiotherapy, 1 month after radiotherapy, 3 months after radiotherapy, 6 months after radiotherapy, every 3 months up to 2 years after randomization
quality of life (QoL) in anal cancer patients
Anal cancer-specific quality of life will be evaluated using the European Organisation for Treatment and Research of Cancer (EORTC) Quality of Life Questionnaires QLQ-ANL27. The scoring and interpretation of the QLQ-ANL27 scales were performed according to the EORTC guidelines.
Time frame: Baseline, 3 days after completion of radiotherapy, 1 month after radiotherapy, 3 months after radiotherapy, 6 months after radiotherapy, every 3 months up to 2 years after randomization
Anal function
Anal function will be evaluated using the Wexner incontinence score. This scoring system consists of 5 items evaluating the frequency of gas incontinence, frequency of liquid incontinence, frequency of solid incontinence, frequency of wearing pads, and lifestyle alterations, with a score ranging from 0-4 for each question. The total score is calculated, with higher scores indicating poorer anal function.
Time frame: Baseline, 3 days after completion of radiotherapy, 1 month after radiotherapy, 3 months after radiotherapy, 6 months after radiotherapy, every 3 months up to 2 years after randomization
PFS
Progression-free survival (PFS) is defined as the time from enrollment to the first documentation of disease recurrence or progression per RECIST 1.1 criteria, or death from any cause, whichever occurs first. For participants without any event, PFS will be censored at the last follow-up.
Time frame: 2 years after randomization
CFS
Colostomy-free survival (CFS) is defined as the time from enrollment to the first occurrence of permanent colostomy (due to tumor residual/recurrence, severe treatment-related toxicity leading to loss of anal function, or disease progression/recurrence) or death from any cause, whichever occurs first. For participants without any event, CFS will be censored at the last follow-up.
Time frame: 2 years after randomization
LRFS
Locoregional recurrence-free survival (LRFS) is defined as the time from enrollment to the first occurrence of locoregional disease progression (local recurrence or regional lymph node recurrence) or death from any cause, whichever occurs first. For participants without any event, LRFS will be censored at the last follow-up. Local recurrence (LR) is defined as the reappearance of tumor in the anal canal, perianal skin, rectum, or anastomotic site. Persistent disease (tumor that never achieved clinical complete response \[cCR\] after chemoradiotherapy) is considered an event for statistical analysis, but assessment of residual disease within 6 months after radiotherapy completion is not recommended. Regional lymph node recurrence is defined as the reappearance of tumor in regional lymph node drainage areas within the radiation field, including inguinal, mesorectal, presacral, internal iliac, external iliac, and obturator lymph nodes.
Time frame: 2 years after randomization
DMFS
Distant metastasis-free survival (DMFS) is defined as the time from enrollment to the first occurrence of distant metastasis or death from any cause, whichever occurs first. For participants without any event, DMFS will be censored at the last follow-up.
Time frame: 2 years after randomization
OS
Overall survival (OS) is defined as the time from enrollment to death from any cause. For participants without any event, OS will be censored at the last follow-up.
Time frame: 2 years after randomization
Rate of treatment interruption
The proportion of any unplanned radiotherapy interruptions during the scheduled radiotherapy course due to treatment-related adverse events.
Time frame: 2 years after randomization
Plan to share: No
No publications or documents are linked to this record.
Started Mar 2026 (actual). Primary completion is estimated for Mar 2029, 36 months after the start.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Sintilimab
Cancer Institute and Hospital, Chinese Academy of Medical Sciences →