Spontaneous Perforation of Pyometra Presenting as Acute Abdomen and Pneumoperitoneum Mimicking Those of Gastrointestinal Origin

Gastrointestinal (GI) perforation accounts for over 90% of acute abdomen and pneumoperitoneum. The presence of pneumoperitoneum secondary to spontaneously perforated pyometra is an interesting yet confusing finding given the absence of gastrointestinal (GI) perforation, because pyometra is more common in postmenopausal women. We report an instructive case of diffuse peritonitis caused by spontaneous perforation of pyometra. A 70-year-old postmenopausal female was admitted to surgical emergency with signs of diffuse peritonitis. After resuscitation, an emergency laparotomy was performed because of suspicion of GI perforation. At laparotomy, about 2,000 mL of purulent fluid was found to be present in peritoneal cavity, while GI tract was intact. A rent with a diameter of 5 mm was found on anterior fundus of uterus. A total abdominal hysterectomy with a bilateral salpingo-oophorectomy was performed. Despite intensive care and a course of antibiotics, the patient died of multiple organ failure resulting from sepsis on postoperative day 16. Our case illustrates the importance of clinical knowledge of acute gynecological diseases, which are not uncommonly encountered by the general surgeon. Moreover, good appreciation of pelvic anatomy and close collaboration with gynecology and GI surgery colleagues is essential as operative intervention is often required

Spontaneous regression of advanced transverse colon cancer with deficient mismatch repair: a case report

Abstract Background Spontaneous regression (SR) of cancer occurs in 1 in 60,000–100,000 patients. This phenomenon has been reported in almost all cancer types, most commonly neuroblastoma, renal cell carcinoma, malignant melanoma, and lymphoma/leukemia. However, SR in colorectal cancer (CRC) is extremely rare, particularly in advanced cases. Hence, this report describes a very rare case of spontaneous regression of advanced transverse colon cancer. Case presentation A 76-year-old female with anemia was diagnosed with a type II well-differentiated adenocarcinoma in the middle transverse colon. Two months later, a second colonoscopy examination was performed for preoperative marking, and it revealed tumor shrinkage and a shift to type 0–IIc morphology. Endoscopic tattooing was then performed, followed by a laparoscopic partial resection of the transverse colon with D3 lymph node dissection. However, the resected specimen contained no tumor, and colonoscopy showed no tumor remnants in the remaining colon. Histopathological examination revealed mucosal regeneration and a mucus nodule in between the submucosal and muscular layers, with no cancer cells detected. Immunohistochemical analysis revealed the loss of MutL homolog 1 (MLH1) and postmeiotic segregation increased 2 (PMS2) expression in the cancer cells of biopsied specimens, suggesting deficient mismatch repair (dMMR). The patient continues to be followed up until 6 years postoperatively, and no recurrence has been observed. In this study, we also reviewed similar reported cases of spontaneous regression of cancer involving dMMR. Conclusion This study presents a rare case of spontaneous regression of advanced transverse colon cancer wherein dMMR is strongly involved. However, further accumulation of similar cases is needed to elucidate this phenomenon and to develop new treatment strategies for CRC

Studying the Lunar Ionosphere with SELENE Radio Science Experiment

Radio occultation observations of the electron density near the lunar surface were conducted during the SELENE (Kaguya) mission using the Vstar and Rstar sub-satellites. Previous radio occultation measurements conducted in the Soviet lunar missions have indicated the existence of an ionosphere with peak densities of several hundreds of electrons per cubic centimeters above the dayside lunar surface. These densities are difficult to explain theoretically when the removal of plasma by the solar wind is considered, and thus the generation mechanism of the lunar ionosphere is a major issue, with even the validity of previous observations still under debate. The most serious error source in the measurement is the fluctuation of the terrestrial ionosphere which also exists along the ray path. To cope with this difficulty, about 400 observations were conducted using Vstar to enable statistical analysis of the weak signal of the lunar ionosphere. Another method is to utilize Vstar and Rstar with the second one being used to measure the terrestrial ionosphere contribution. The observations will establish the morphology of the lunar ionosphere and will reveal its relationship with various conditions to provide possible clues to the mechanism