Large cell neuroendocrine carcinoma of the colon: An unexpected diagnosis: A case report.

INTRODUCTION AND IMPORTANCE: Large cell neuroendocrine carcinomas of the colon (LCNECC) are exceptionally rare, comprising only 0.2 % of all colonic carcinomas. Their diagnosis poses a significant challenge due to their propensity to mimic colonic adenocarcinomas. Typically diagnosed at advanced stages, LCNECCs carry a grim prognosis. Herein, we present a rare case of LCNECC and aim to elucidate its clinico-pathological characteristics. CASE PRESENTATION: A 56-year-old female patient presented with complaints of constipation, abdominal pain, and weight loss. On physical examination, a sizable mass was palpable in the right flank. Colonoscopy revealed a polyp in the descending colon and a friable multinodular stenosing mass in the ascending colon. Microscopic examination of the biopsy from the ascending colon mass exhibited a poorly differentiated large cell carcinomatous proliferation with positivity for synaptophysin and CD56, along with a Ki-67 proliferation index of 50 %. The polyp in the descending colon was consistent with a low-grade dysplastic tubular adenoma. A diagnosis of LCNECC with synchronous low-grade dysplastic tubular adenoma was established. A right hemicoloctomy was performed. Final pathological examination confirmed LCNECC invading the muscularis propria, with lymph node metastases. The tumor was classified as pT2N1M0 (Stage III). CLINICAL DISCUSSION: LCNECCs often mimic adenocarcinomas clinically, endoscopically, and radiologically. Pathological examination is the key for diagnosis. An immunohistochemical study using neuroendocrine markers is imperative to prevent overlooking the diagnosis of LCNECC. CONCLUSION: LCNECCs represent rare aggressive carcinomas. Their diagnosis might be challenging. A better knowledge of this rare entities would enable early diagnosis.

Epidemiological and histopathological characteristics of thyroid carcinoma in a Tunisian health care center.

Background: Thyroid carcinoma (TC) accounts for almost 0.5%-1% of total malignancies. Its incidence is increasing rapidly worldwide. Several studies have drawn up the epidemiological profile of TC and its clinical and pathological features. However, to date, no similar studies have been conducted in Tunisia. Aims: To establish an epidemiological profile of TC in a Tunisian health care institute and to analyze its clinical and histopathological characteristics in our institute. Materials and Methods: We present a retrospective study reviewing the cases of TC diagnosed in our institution in a 4-year period. Results: We collected a sample of 192 cases of TC. It consisted of 31 males and 161 females (83.8%) with a sex-ratio M/F of 0.19. The mean age was 46.4 years. Papillary thyroid carcinoma was the most frequent histological subtype. The multifocality rate was 33.8%. The mean size of TC was 2.2 ± 1.9 cm. 60.9% of TC were staged pT1 and 20.3% had nodal involvement. Papillary thyroid microcarcinomas were noted in 37.5% of cases. Conclusion: Our results were consistent with those of the literature. A high proportion of pT1 and pN0 tumors were noted in our series, suggesting that TC's diagnosis and management was performed at an early stage of the disease in our institution. In addition, our study enabled us to notice the impact of the Coronavirus disease 19 crisis on the management of TC in our institution. Further studies are needed to establish the epidemiological profile of TC in Tunisia and to assess its clinical and pathological features.

Pelvic leiomyoma associated with intermediate risk prostate cancer: A case report.

Pelvic leiomyoma in male patients is a very rare occurrence and its association with prostate cancer is a unique clinical situation. This study reports a new case of a 9 cm pelvic Leiomyoma associated with intermediate-risk localized prostate cancer in a 68-year-old patient. The leiomyoma was discovered fortuitously after an MRI was performed in the context of prostate cancer work-up. Surgical excision of the pelvic mass along with a radical prostatectomy were performed and the diagnosis of leiomyoma was confirmed by histopathology.

Hemangioma of the umbilical cord: A case report on a rare entity.

Several hundred cases of placental hemangiomas have been reported in the literature. However, the umbilical cord is extremely uncommon as a site of occurrence. We present a case of postnatal discovery of giant hemangioma of the umbilical cord (HUM) in a Coronavirus Disease 2019 (COVID 19) positive mother. To our knowledge, this is the first reported case of HUM synchronous to a maternal infection with COVID 19. We aim, through this case and a review of the literature, to study the clinicopathological characteristics of this singular entity. Our patient, a 37-year-old woman, presented to the Department Of Obstetrics And Gynecology for respiratory distress and loss of fetal movements. Ultrasound examination concluded to intrauterine fetal desmise. After stabilization of the patient, a cesarean section was performed. A macerated fetus was extracted. Placenta showed a giant mass attached to the cord. It was submitted for pathological examination. Gross examination showed that the umbilical cord was inserted eccentrically with a fusiform dilation. Near its placental end, three cohesive solid angiomatous nodules were noted. Microscopic examination revealed lobules of dilated blood-filled capillaries set in a myxoid stroma. The diagnosis of HUM have been established. HUM arise from endothelial cells of the umbilical vessels. Their etiology, physio-pathology and pathways of tumorigenesis are not yet well defined. Further studies are needed to explore the pathways of tumorigenesis and to determin the implication of COVID-19 in HUM.

Incidental discovery of a Hodgkin lymphoma synchronous to a papillary thyroid carcinoma.

Papillary thyroid carcinoma is the most common type of thyroid cancer and accounts for almost 89.4% of all thyroid carcinomas. Hodgkin lymphoma is a heterogeneous group of neoplasms and represents 10% of lymphomas. These two cancers do not share the same risk factors. Some studies have reported the association of thyroid papillary carcinoma with lymphomas, mainly Hodgkin's lymphoma, treated with radiotherapy. However, to our knowledge less than 10 cases have illustrated synchronous papillary thyroid carcinoma and Hodgkin lymphoma with no history of radiotherapy. We present the case of a 49-year-old female patient, with no history of past exposure to radiation, who was incidentally diagnosed with Hodgkin lymphoma during the work up for papillary thyroid carcinoma. Our patient had total thyroïdectomy with cervical lymphadenectomy. The histopathologic examination concluded to a papillary thyroid carcinoma of classical variant. And the lymph node dissection enabled us to diagnose not only papillary thyroid carcinoma's lymph node metastasis, but also Hodgkin Lymphoma. This discovery of the Hodgkin lymphoma was totally incidental. The discovery of synchronous tumors in patients with papillary thyroid carcinoma has been reported in the literature. However, the diagnosis of Hodgkin through lymph node dissection for papillary thyroid carcinoma is extremely rare. This underlines the singularity and the importance of our case. The synchronous papillary thyroid carcinoma and Hodgkin lymphoma is a rare condition, which may pose significant diagnostic and treatment dilemmas. To date, there is no standardized approach due to lack of experience. The molecular mechanisms of this link are poorly understood and yet remain to be elucidated.

Case Report: Incidental discovery of primary peritoneal psammocarcinoma.

Psammocarcinoma is an uncommon subtype of low-grade serous carcinoma. It is characterized by the presence of extensive psammoma bodies and can have either an ovarian or peritoneal origin. To our knowledge fewer than 30 cases of primary peritoneal psammocarcinoma (PPP) have been reported in the English literature. We report a rare case of  PPP in a 74-year-old female, discovered fortuitously within a laparotomy for gallbladder lithiasis. At laparotomy, multiple nodular implants involving the omentum, the peritoneum and a magma of intestinal loops in the right iliac fossa were noted. A biopsy from nodules was performed. Gross examination showed multiple nodules of different sizes in the fat tissue. Pathologic examination showed massive psammoma bodies representing more than 75% of the tumor. The final diagnosis was psammocarcinoma. Our patient was referred to the gynecologic department for further investigation and to ascertain whether the tumor arose from the ovaries or peritoneum. Hysterectomy, bilateral adnexectomy and omentectomy were performed. Macroscopic examination showed that both ovaries were intact having a normal size. No invasion of ovarian stroma was shown in microscopic examination. The patient died of SARS-CoV-2 (COVID-19) six days after the surgery. PPP is a rare type of  low-grade serous carcinoma. The behavior of this tumor is unclear, and the treatment is not standardized because of its rarity and lack of long-term follow-up. More cases need to be studied for better understanding and improvement of the management protocols.