Automatic Production and Preliminary PET Imaging of a New Imaging Agent [18F]AlF-FAPT

BackgroundFibroblast activating protein (FAP) has become an important target for cancer diagnostic imaging and targeted radiotherapy. In particular, [18F]FAPI-42 has been successfully applied to positron emission tomography (PET) imaging of various tumors. However, it exhibits high hepatobiliary metabolism and is thus not conducive to abdominal tumor imaging. This study reports a novel 18F-labeled FAP inhibitor, [18F]AlF-FAPT, a better FAPI imaging agent than [18F]FAPI-42.Materials and MethodsThe precursor of [18F]AlF-FAPT (NOTA-FAPT) was designed and synthesized using the standard FMOC solid phase synthesis method. [18F]AlF-FAPT was subsequently synthesized and radiolabeled with 18F using the AllInOne synthesis module. Dynamic MicroPET and biodistribution studies of [18F]AlF-FAPT were then conducted in xenograft tumor mouse models to determine its suitability.ResultsThe precursors NOTA-FAPT were obtained with a chemical purity of > 95%. [18F]AlF-FAPT was synthesized automatically using the cassette-based module AllInOne within 40 min. The non-decay corrected radiochemical yield was 25.0 ± 5.3% (n=3). In vivo imaging and biodistribution studies further demonstrated that compared with [18F]-FAPI-42, [18F]AlF-FAPT had a lower hepatobiliary uptake than [18F]FAPI-42, which was advantageous for imaging abdominal tumors.Conclusion[18F]AlF-FAPT can be synthesized automatically using a one-step method of aluminum fluoride. Collectively, [18F]AlF-FAPT is a better FAPI imaging agent than [18F]FAPI-42. This study proves the feasibility of using [18F]AlF-FAPT as a new radioactive tracer for PET imaging.

Gastric adenocarcinoma with germ cell tumor components: a rare case report

Germ cell tumors (GCTs) often occur in male testes and female ovaries. Extragonadal GCTs account for approximately 2% to 5% of all GCTs and mainly occur in the mediastinum, retroperitoneum, and pineal gland. In this study, we reported a rare case of gastric adenocarcinoma with GCT components. The patient’s serum α-fetoprotein (AFP) level was higher than normal. Abdominal computed tomography (CT) showed a 10-cm × 10-cm tumor between the spleen and the bottom of the stomach. Gastric endoscopy indicated an ulcerative lesion extending from the bottom of the stomach to the antrum. Tissue biopsy identified the tumor as an adenocarcinoma. The patient underwent abdominal tumor resection, subtotal gastrectomy, D2 lymphadenectomy, and splenectomy. Postoperative histopathology showed that the tumor was a moderately to poorly differentiated adenocarcinoma. Immunohistochemistry analysis revealed positive staining for AFP, glypican-3, and placental alkaline phosphatase. Gastric adenocarcinoma with GCT components is particularly uncommon and rarely reported. Elevated serum AFP and/or β-human chorionic gonadotropin levels, abdominal CT, histopathology, and immunohistochemistry may help diagnose GCTs. Radical surgery resection is the primary treatment method for GCTs. Adjuvant chemotherapy and radiotherapy are effective for advanced GCTs.

An unusual case of small bowel obstruction secondary to internal herniation of distal ileum through a rent between adhered inflamed vermiform appendix and appendices epiploicae

Intestinal obstruction secondary to an internal hernia is rare and that occurring through a rent between the adhered inflamed vermiform appendix and appendices epiploicae of the proximal caecum is so rare that this case was the first of its kind ever to be reported. Such a cause for obstruction should be suspected in a patient with a virgin abdomen with no history/clinical features of an obstructing external hernia or abdominal tumor. A 28 year old man presented to the ER with features of intestinal obstruction, in whom CECT abdomen revealed multiple dilated small bowel loops with breaking-of seen in the region of the terminal ileum. Surgical exploration revealed internal herniation of the distal ileum through a rent between the adhered inflamed vermiform appendix and the appendices epiploicae of the proximal caecum; reduction of which was sufficient to relieve the obstruction and demonstrate healthy reperfusion. Adhesiolysis, epiploicae appendectomy and appendectomy was done with no other points of obstruction along the small bowel. Due to its rarity, non-specific presentation pattern and limited usefulness of imaging for diagnosis, a high index of suspicion with prompt early surgical exploration is a must for a successful outcome in such cases intestinal obstruction; especially in a virgin abdomen.

A huge mesenteric teratoma in reproductive age woman: a case report

The incidence of dermoid ovarian cyst is 15-20% of all ovarian neoplasm, which is a common entity. Mesenteric cyst are one of the very rare entities with incidence of 1 in 2, 50, 000. Dermoid cysts rarely present as mesenteric cysts. Mesenteric dermoid cyst have good prognosis. Here, we report a rare abdominal tumor which was initially diagnosed clinically as an ovarian dermoid cyst but operative and histology revealed it to be mesenteric dermoid cyst. A 36 year-old, multiparous presented with abdominal mass, gradually increasing in size since 1 year with recent onset of abdominal pain. Physical examination revealed abdominal mass of 22×20 cm size, globular, non-tender, mobile, and cystic to solid in consistency. Contrast-enhanced computed tomography (CECT) showed 23×21×14.4 cm heterogeneous enhancing mass lesion with areas of fat density and calcifications within, suggestive of neoplastic mass lesion, likely teratoma. Tumor markers were within normal limit. Patient was managed surgically. Laparotomy findings revealed a huge solid mesenteric mass (22×20 cm) weighing 6.5 kgs. Histopathology showed mature cartilage, osteoid formation, fibro-adipose connective tissue, focal lymphoid aggregates, congested blood vessels and focal mature neuronal component and no immature elements seen, confirming dermoid cyst. Mesenteric cyst are rare intra-abdominal tumor found most commonly in ileum (60%) next is ascending colon (40%). However, if a mesenteric cyst locates within the pelvic cavity, as in this case, it may be misdiagnosed as an ovarian cyst.

Neoadjuvant concurrent chemoradiotherapy with and without hyperthermia in retroperitoneal sarcomas: feasibility, efficacy, toxicity, and long-term outcome

Purpose Retroperitoneal (RPS) sarcomas are associated with poor local and abdominal tumor control. However, the benefit of preoperative radio- or chemotherapy alone for these entities is currently unclear. Moreover, as intermediate- and high-grade sarcomas have a tendency toward early metastasis, exploration of neoadjuvant strategies is of high importance. This analysis reports the results of our 20-year single-institution experience with preoperative neoadjuvant concurrent chemoradiation. Methods From 2000–2019, 27 patients with intermediate- or high-grade RPS (12 dedifferentiated liposarcoma, 10 leiomyosarcoma, 5 others) were treated with radiotherapy (median dose: 50.4 Gy; range 45–75 Gy) and two cycles of chemotherapy (doxorubicin 50 mg/m2 BSA/d3 q28 and ifosfamide 1.5 g/m2 BSA/d1‑5 q28) in neoadjuvant intent. Chemotherapy consisted of doxorubicin alone in two cases and ifosfamide alone in one case. Fifteen patients (56%) additionally received deep regional hyperthermia. Results The median follow-up time was 53 months (±56.7 months). 92% of patients received two cycles of chemotherapy as planned and 92% underwent surgery. At 5 and 10 years, abdominal-recurrence-free survival was 74.6% (±10.1%) and 66.3% (±11.9%), distant metastasis-free survival was 67.2% (±9.7%) and 59.7% (±11.1%), and overall survival was 60.3% (±10.5%) and 60.3% (±10.5%), respectively. CTC grade III and IV toxicities were leukocytopenia (85%), thrombocytopenia (33%), and anemia (11%). There were no treatment-related deaths. Conclusion Neoadjuvant chemoradiotherapy with and without hyperthermia for retroperitoneal sarcomas is feasible and provided high local control of intermediate- and high-grade sarcoma.

Large and acute symptomatic abdominal tumor in newborns: pitfalls, difficulties in management and surgical decision making.

Large and rapidly growing abdominal tumors endanger vital prognosis in neonates. Sometimes, quickly worsening patients’ clinical conditions demand surgical decision-making that cannot wait for precise histological diagnosis. There is neither consensus nor rules to manage these situations. We presented our experience with five patients and we looked in the literature for the best possible management of such rare disease. Laparostomy should be considered only as a safe-life procedure and if the liver is affected by the tumor and a coagulopathy is present, the prognosis is often compromised.

Synchronous multiple primary malignant neoplasms: a case report of malignant peritoneal mesothelioma and neuroendocrine rectal tumor

We report a rare case of synchronous malignant peritoneal mesothelioma of the biphasic histological type and neuroendocrine tumor (NET) of the rectum without history of asbestos exposure. During 2 years since manifestation of the disease the patient underwent 3 cytoreductive surgeries (CRS): removal of the tumor of the sigmoid mesentery, resection of the rectosigmoid junction completeness of cytoreduction (CC) 0 (2017), omentectomy and partial parietal peritonectomy CC-0 (2017), atypical resection of S2, S4, S5 liver, the removal of the abdominal tumor with left-sided en-block hemicolectomy, partial parietal peritonectomy, argon-plasma coagulation of tumor foci on the mesentery of the small intestine CC-2 (2018) and Transanal Minimally Invasive Surgery-removal of neuroendocrine rectal tumor (2017). The patient underwent hyperthermic intraperitoneal chemotherapy (HIPEC) twice (during 2nd and 3rd CRS). Different regimens of HIPEC were performed: cisplatin + doxorubicin (2017) and metamycin C (2018). The patient received 4 courses of adjuvant chemotherapy with cisplatin plus pemetrexed in 2017 and 3 courses of the chemotherapy with gemcitabine and carboplatin plus bevacizumab in 2018. The patient survived 21 months after the detection of malignant peritoneal mesothelioma in 2017 and died 4 months after the last cytoreductive surgery from the progression of the disease. Histological subtype of MPMP remains important factor in the prognosis of the disease even on the early stages though patient had received the most aggressive variant of special treatment. Minimally invasive treatment tactics of NET demonstrated clinical effectiveness.

Recurrence of Adult Granulosa Cell Tumor in the Greater Omentum 11 Years after Surgery

Adult-type ovarian granulosa cell tumors (AGCTs) are very rare tumors that account for <5% of all ovarian carcinomas. AGCTs have low malignancy potential and rarely metastasize 5–30 years after the initial diagnosis. Because time has passed from the first surgery and because recurrence develops in various locations, the differential diagnosis is difficult. In particular, tumors developing in the greater omentum are encountered rarely, and it is necessary to carefully consider the differential diagnosis, including primary and secondary neoplasms. Although CT is useful to detect omental tumors, the diagnosis requires invasive procedures. We report a case of AGCT recurrence in the greater omentum that was resected during laparoscopic cholecystectomy. A patient visited our hospital with right-sided abdominal pain. The CT revealed gallbladder stones, a ureteral stone, and a right abdominal mass. The diagnosis of the abdominal tumor was difficult on the basis of blood biochemical testing, gastrointestinal endoscopy, or image inspection. Although the patient underwent several previous surgeries and there were no findings of malignancy with positron emission tomography, we chose to resect the tumor for combined diagnosis and treatment during laparoscopic cholecystectomy. Intraoperative findings showed that the tumor originated from the greater omentum, and the tumor was diagnosed as AGCT recurrence by pathology. A recurrence of AGCT in the greater omentum is very rare, and laparoscopic surgery was safe and useful for resection, in our case.