(Disclaimer: This article is for scientific purposes only. To protect the patient’s privacy, the relevant information in the following content has been processed) Abstract: The patient came to the clinic because of persistent pain in the right lower abdomen accompanied by fever, which could not be relieved on its own after medication. The diagnosis of appendiceal adenocarcinoma was confirmed by physical examination, ultrasound, abdominal CT plain scan plus enhancement scan, and puncture. Through surgery + medication, the patient’s abdominal distension and abdominal pain were significantly relieved and his condition was under control. As appendiceal adenocarcinoma has no specific symptoms in the early stage, its clinical manifestations are very similar to appendicitis and periappendiceal abscess, so it is necessary to pay attention to differentiate it. Basic information] Female, 68 years old [Type of disease] Adenocarcinoma of the appendix [Hospital] The First Affiliated Hospital of Kunming Medical University [Date of consultation] January 2022 [Treatment plan] Surgery (radical right hemicolectomy) + medication (cefoperazone sodium tazobactam sodium for injection) [Treatment period] Hospitalization for 2 weeks [Effect of treatment] Abdominal distension and pain were relieved and the disease was under control, Initial Consultation One month ago, the patient was sent to the hospital by her family because of abdominal pain. At that time, I happened to be on duty in the outpatient clinic, and when I saw the patient, I observed that she was pale, in poor spirits, and suffered from severe pain in the right lower part of her body, so I asked her family members about the specifics of her condition. Family members described that three days ago, do not know what the cause of the right lower abdominal distension and pain, persistent, no obvious abdominal distension, accompanied by fever, the highest temperature of 38.8 ℃, no nausea, vomiting symptoms, go to the home near the health center to check, take drugs (drugs do not know the specifics), the effect is not good to come to the hospital for medical treatment. Upon examination, the body temperature was normal, the abdomen was flat and symmetrical, no gastrointestinal type and peristaltic wave were seen, no abdominal wall varicose veins were seen, abdominal breathing was present, abdominal muscles were slightly tight, pressure and rebound pain in the lower abdomen, a tough mass was palpable in the right lower abdomen, and the bowel sounds were normal. According to the ultrasound examination, the results showed that there was a shadow in the appendix, the patient had a history of kidney stones and penicillin allergy, and was initially considered to have a periappendiceal abscess, and was admitted to the hospital for further diagnosis and treatment. After the patient was admitted to the hospital, he continued to complete routine blood tests, blood glucose, C-reactive protein and other routine tests, the results showed that C-reactive protein and white blood cells were elevated, CT scanning and enhancement scanning of the lower abdomen showed that the cystic solid mass in the ileocecal region, suppurative appendicitis and the possibility of periappendiceal abscess formation, and metronidazole tablets were given to the patient combined with cefixime tablets for symptomatic treatment, and the patient did not see any significant improvement in his abdominal pain. After reviewing the ultrasound examination, the result showed localized fluid accumulation in the right lower abdomen, so he underwent peritoneal puncture catheterization, and the yellowish jelly-like mucous material was aspirated, and no obvious purulent fluid was drained out, so he considered that appendiceal adenoma or appendiceal mucinous adenocarcinoma had a high probability. After communicating with the patient, a laparotomy was performed under general anesthesia, and some of the cysts were sent for intraoperative cryopathological examination, which suggested appendiceal adenocarcinoma, and radical right hemicolectomy was decided to be performed. The operation went smoothly and the patient’s vital signs were monitored after the operation, and then he was sent to the ward and given anti-infection treatment with cefoperazone sodium tazobactam sodium injection. (Abdominal CT) (Pathological examination and diagnosis) III. Treatment effect The patient came to the hospital because of abdominal pain, accompanied by symptoms of abdominal distension, and the outpatient examination results were considered to be a peri-appendiceal abscess, and after admission to the hospital, with the active cooperation of the patient, a series of clinical examinations and diagnosis of the doctor, the diagnosis of appendiceal adenocarcinoma was finally confirmed. After surgery, the patient had no discomfort after the operation and was returned to the ward with anti-infection treatment. One day after the operation, the patient was checked and there was no bleeding from the wound, no infection symptoms, no nausea, vomiting, fever and other symptoms; half a month after the hospitalization, the patient’s physical signs improved, abdominal pain, abdominal distension and other symptoms were gradually relieved, and there were no other irritating reactions, so the patient was arranged to be discharged from the hospital. After being discharged from the hospital, the patient followed the doctor’s instructions and took the medication on time. In the follow-up visit after 1 month, the patient’s color was red, his spirit was good, his appetite gradually recovered, and the discomfort in the lower abdomen was largely relieved, and the patient’s family was satisfied with the treatment after the CT examination. Precautions The patient’s condition was controlled through active treatment, and we are truly happy for her. After the operation, the patient should follow the doctor’s instructions, complete regular review and follow-up, if abdominal pain, fatigue, low-grade fever and other symptoms, be sure to contact the doctor in time, the review includes blood tests, abdominal ultrasound, abdominal CT and so on. Undergoing treatment or in ordinary life, keep an optimistic mindset, avoid excessive anxiety, and actively cooperate with your doctor to help your body recover. Diet, mainly light diet, can eat some easy-to-digest food after surgery, such as egg custard, etc. Avoid spicy and stimulating food. At the beginning of the postoperative period, it is recommended to carry out slow and small-amplitude activities in moderation, and then carry out slightly more intense exercises after 6 months. V. Personal perception Appendiceal adenocarcinoma is a rare disease, because there are no specific symptoms and signs, and the clinical manifestations are very similar to acute and chronic appendicitis, and often combined with appendicitis, so it is very easy to misdiagnose, and it is difficult to diagnose it in preoperative examination, and it is necessary to carry out pathological examination to confirm the diagnosis of this disease, and the treatment of this disease is mainly based on surgery, supplemented by chemotherapy. The patient in this case came to our hospital because she had abdominal pain 3 days ago and had received treatment at the health center, which was not effective. On examination, a mass was felt in the abdomen, and according to the ultrasound, a shadow was found in the area of the appendix. At the time of admission, a periappendiceal abscess was initially considered, and the treatment was ineffective; intraoperative diagnosis was appendiceal adenocarcinoma, and radical right hemicolectomy was performed, and the patient recovered well after the operation. Therefore, if there is pain in the right lower abdomen, after excluding the possibility of appendicitis, we must be alert to whether it is appendiceal adenocarcinoma. I was especially happy and had a sense of pride when I looked at the smile that re-bloomed on the patient’s face, which is also the mission of a doctor.