Coexistence of carcinoid tumor and adenocarcinoma of the lung; morphological, immunohistochemical and genetic analyses, a case report

Background

Pulmonary carcinoid tumors rarely coexist with non-small cell lung carcinoma, and only nine cases have been reported previously. The pathogenesis and origin of these combined tumors remain unclear because of its rarity.

Case presentation

We examined two cases of adenocarcinoma coexisting with a typical or atypical carcinoid tumor: Case 1 was a 77-year-old woman and Case 2 was an 83-year-old woman. Both of these cases had no respiratory symptoms, and underwent pulmonary lobectomies due to incidentally detected lung nodules. Recurrence and metastases were not detected after the surgery. Histologically, carcinoid and adenocarcinoma components were present in both cases. The two components coexisted without mixing with each other. Next-generation sequencing was performed on the two components in these cases. In each case, no common genetic variants were detected.

Conclusion

We considered that our cases could histologically and genetically represent collision tumors that did not share common progenitor cells. Comprehensive analyses such as whole genome sequencing could provide important information for elucidating the pathogenesis of adenocarcinoma and carcinoid components.

Focal nodular hyperplasia associated with a giant hepatocellular adenoma: A case report and review of literature

BACKGROUND

Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) are well-known benign liver lesions. Surgical treatment is usually chosen for symptomatic patients, lesions more than 5 cm, and uncertainty of diagnosis.

CASE SUMMARY

We described the case of a large liver composite tumor in an asymptomatic 34-year-old female under oral contraceptive for 17-years. The imaging work-out described two components in this liver tumor; measuring 6 cm × 6 cm and 14 cm × 12 cm × 6 cm. The multidisciplinary team suggested surgery for this young woman with an unclear HCA diagnosis. She underwent a laparoscopic left liver lobectomy, with an uneventful postoperative course. Final pathological examination confirmed FNH associated with a large HCA. This manuscript aimed to make a literature review of the current management in this particular situation of large simultaneous benign liver tumors.

CONCLUSION

The simultaneous presence of benign composite liver tumors is rare. This case highlights the management in a multidisciplinary team setting.

A Gastric Intramucosal Mixed Adenocarcinoma-Neuroendocrine Tumor

Gastric mixed adenocarcinoma-neuroendocrine tumor (NET) is a rare composite tumor, and a limited number of studies have reported on it. A 77-year-old man was admitted to our hospital because of acute cholecystitis. He underwent a cholecystectomy. Esophagogastroduodenoscopy during his admission revealed a slightly elevated tumor, and biopsy demonstrated a well-differentiated tubular adenocarcinoma. The tumor was resected completely by endoscopic submucosal dissection. Histological findings showed that it measured 9 mm in diameter, was located within the mucosa, and consisted of well-differentiated tubular adenocarcinoma and a NET G1. The NET was covered with adenocarcinoma and both components exhibited histological continuity. The NET and a part of the adenocarcinoma component showed a positive reaction for chromogranin A and synaptophysin. Neither enterochromaffin-like cell hyperplasia nor endocrine cell micronest surrounded the tumor. The diagnosis was gastric mixed adenocarcinoma-NET. The histological continuity between the two components can be likened to the same histogenesis.

Does Mixed Neuroendocrine-Nonneuroendocrine Neoplasm (MiNEN) of the Parathyroid Gland Exist? First Description of a Possible Case

We describe the histological, histochemical, and immunohistochemical features of an unusual neoplasm of the parathyroid gland showing the histologic criteria of a mixed neuroendocrine-nonneuroendocrine neoplasm (MiNEN). To the best of our knowledge, this is the first report of such a tumor. A 43-year old male presented with acute and severe abdominal pain due to acute pancreatitis. On physical examination a painless lump in the right neck was detected and laboratory analyses revealed hyperparathyroidism (parathormone: 146 pmol/L, normal range 1.05-6.83) and hypercalcemia (calcium level: 3.02 mg/dL, normal range 2.25-2.5), which fell to 2.55 mg/dL after parathyroidectomy. Histologically, the tumor was a parathyroid carcinoma associated with a mucous secreting adenocarcinoma also confirmed by histochemical (Alcian blue-periodic acid Schiff) and immunohistochemical stainings. The present case expands the spectrum of MiNENs that can be found in endocrine organs.

Ovarian yolk sac tumor with epithelial tumor component in a postmenopausal woman - case report and literature review

Ovarian yolk sac tumors are common germ cell tumors usually arising in young women. Yolk sac tumors in elderly women are infrequently encountered and most of them are combined with other epithelial tumor components including endometrioid carcinoma or serous carcinoma. Here, we report an extremely rare case of a yolk sac tumor with mucinous tumor and large cell neuroendocrine carcinoma components in a postmenopausal woman, which is the third yolk sac tumor case with a neuroendocrine tumor element in an elderly woman. An 82-year-old female visited our hospital due to abdominal distention. Abdominal computed tomography (CT) demonstrated a solid and cystic mass, measuring about 9.0 cm in the largest diameter. A total hysterectomy with bilateral salpingo-oophorectomy and excisional biopsy of the peritoneal metastatic lesions was performed. Histologic evaluation revealed a malignant ovarian tumor composed of a variety of tumor components, including a yolk sac tumor, a mucinous tumor with multifocal mucinous carcinomatous areas, and a large-cell neuroendocrine carcinoma. After surgery, the patient refused further treatment and the disease recurred in the pelvic peritoneum and a left supraclavicular lymph node nine months later.

Composite trichoblastoma and inverted follicular keratosis: a case report

Composite trichoblastoma and inverted follicular keratosis is extremely rare and the histogenesis is unclear. To date, only four cases have been described in a report. We report a case of 62-year-old woman patient with a palpable cutaneous nodule on the buttock. The patient had a history of squamous cell carcinoma on the lower lip 13 months ago. Excisional biopsy was done, and the microscopic examination revealed composite tumor of trichoblastoma and inverted follicular keratosis. The patient has not been experienced recurrence after surgery.

Mixed Neuroendocrine-Nonneuroendocrine Neoplasms (MiNENs): Unifying the Concept of a Heterogeneous Group of Neoplasms

The wide application of immunohistochemistry to the study of tumors has led to the recognition that epithelial neoplasms composed of both a neuroendocrine and nonneuroendocrine component are not as rare as traditionally believed. It has been recommended that mixed neuroendocrine-nonneuroendocrine epithelial neoplasms are classified as only those in which either component represents at least 30 % of the lesion but this cutoff has not been universally accepted. Moreover, since their pathogenetic and clinical features are still unclear, mixed neuroendocrine-nonneuroendocrine epithelial neoplasms are not included as a separate clinicopathological entity in most WHO classifications, although they have been observed in virtually all organs. In the WHO classification of digestive tumors, mixed neuroendocrine-nonneuroendocrine neoplasm is considered a specific type and is defined as mixed adenoneuroendocrine carcinoma, a definition that has not been accepted for other organs. In fact, this term does not adequately convey the morphological and biological heterogeneity of digestive mixed neoplasms and has created some misunderstanding among both pathologists and clinicians. In the present study, we have reviewed the literature on mixed neuroendocrine-nonneuroendocrine epithelial neoplasms reported in the pituitary, thyroid, nasal cavity, larynx, lung, digestive system, urinary system, male and female genital organs, and skin to give the reader an overview of the most important clinicopathological features and morphological criteria for diagnosing each entity. We also propose to use the term "mixed neuroendocrine-nonneuroendocrine neoplasm (MiNEN)" to define and to unify the concept of this heterogeneous group of neoplasms, which show different characteristics mainly depending on the type of neuroendocrine and nonneuroendocrine components.

Composite Paraganglioma and Neuroblastoma of the Urinary Bladder: A Rare Histopathological Entity

Paraganglioma of the urinary bladder is an uncommon clinical entity. Neuroblastoma of the urinary bladder is another rare tumor with only 7 reported cases, all in children. This report presents the case of a composite paraganglioma and neuroblastoma in a 45 year-old male who presented with dysuria and flank pain. On the computerized tomography scan, the bladder wall overlying the tumor was smooth and the mass had a large exophytic component. The initial diagnosis was paraganglioma on transurethral resection. Following partial cystectomy and bilateral pelvic lymph node dissection, pathology confirmed a composite tumor consisting of paraganglioma and neuroblastoma. To our knowledge, this is the first report of such a composite tumor involving the bladder.

Composite Tumor Associating Trichoblastoma and Seborrheic Keratosis

Seborrheic keratosis is a common benign epidermal tumor histologically composed of basaloid and squamous cells. It mainly occurs on the face, scalp, and trunk, and presents clinically as a well-circumscribed, brownish to black papule, nodule, or plaque. Trichoblastoma is a relatively rare benign, slow-growing tumor showing differentiation toward the primitive hair follicle. It clinically manifests as a solitary, skin to erythematous colored, well-circumscribed dermal nodule located predominantly on the head and neck with a predilection for the scalp. Histologically, a well-demarcated mass of follicular germinative cells that show various degrees of differentiation, arranged in lobules, sheets, and nests, is located in the dermis or subcutaneous fat layer. We report the case of a 28-year-old female patient with a solitary, 2.0×4.0-cm black plaque with a 0.7-cm skin-colored nodule on the scalp. Histologically, the entire black plaque had prominent hyperkeratosis, acanthosis, and papillomatosis with horn cysts. The central nodule showed well-circumscribed, various-sized dermal tumor lobules without a connection to the overlying epidermis. The lobular aggregation was composed of numerous basaloid epithelial nests and multiple primitive papillary structures with distinct peripheral palisading of nuclei. According to these findings, the scalp lesion was diagnosed as a composite tumor associating trichoblastoma and seborrheic keratosis.

Mixed adenoneuroendocrine carcinoma of gastrointestinal tract: report of two cases

Mixed adenoneuroendocrine carcinoma (MANEC) is a rare tumor of the gastrointestinal tract that consists of a dual adenocarcinomatous and neuroendocrine differentiation, each component representing at least 30% of the tumor. To date, only seven cases have been reported in the cecum, and less than 40 in the stomach. Our first case was diagnosed in a 74-years-old female as a polypoid lesion of the cecum with direct invasion in the transverse colon, without lymph node metastases. The second case was diagnosed in the stomach of a 46-years-old male as a polypoid tumor of the antral region that invaded the pancreas and presented metastases in 22 regional lymph nodes. The metastatic tissue was represented by the glandular component. In both cases, the tumor consisted of a moderately-differentiated tubular adenocarcinoma (with mucinous component in Case 1) intermingled with neuroendocrine carcinoma. Ki67 index was lower than 20% in Case 1, respectively higher than 20% in Case 2. The neuroendocrine component was marked by synaptophysin and neuron specific enolase, being negative for Keratins 7/20. The neuroendocrine component represented 60% in Case 1, and 40% in Case 2, respectively. The glandular components were marked by carcinoembryonic antigen, maspin and keratin 20/7 (Case 1/2). Both cases were proved to be microsatellite stable. Independently by the localization and tumor stage, MANECs appear to be highly malignant tumors, with high risk for distant metastases. The aggressiveness seems to depend on the endocrine component, independent of its proportion. The neuroendocrine component could be a dedifferentiated adenocarcinoma with a neuroendocrine phenotype.

Mixed adenoneuroendocrine carcinoma of gastrointestinal tract: Report of two cases

Mixed adenoneuroendocrine carcinoma (MANEC) is a rare tumor of the gastrointestinal tract that consists of a dual adenocarcinomatous and neuroendocrine differentiation, each component representing at least 30% of the tumor. To date, only seven cases have been reported in the cecum, and less than 40 in the stomach. Our first case was diagnosed in a 74-years-old female as a polypoid lesion of the cecum with direct invasion in the transverse colon, without lymph node metastases. The second case was diagnosed in the stomach of a 46-years-old male as a polypoid tumor of the antral region that invaded the pancreas and presented metastases in 22 regional lymph nodes. The metastatic tissue was represented by the glandular component. In both cases, the tumor consisted of a moderately-differentiated tubular adenocarcinoma (with mucinous component in Case 1) intermingled with neuroendocrine carcinoma. Ki67 index was lower than 20% in Case 1, respectively higher than 20% in Case 2. The neuroendocrine component was marked by synaptophysin and neuron specific enolase, being negative for Keratins 7/20. The neuroendocrine component represented 60% in Case 1, and 40% in Case 2, respectively. The glandular components were marked by carcinoembryonic antigen, maspin and keratin 20/7 (Case 1/2). Both cases were proved to be microsatellite stable. Independently by the localization and tumor stage, MANECs appear to be highly malignant tumors, with high risk for distant metastases. The aggressiveness seems to depend on the endocrine component, independent of its proportion. The neuroendocrine component could be a dedifferentiated adenocarcinoma with a neuroendocrine phenotype.

A gastric composite tumor with an adenocarcinoma and a neuroendocrine carcinoma: a case report

A 70-year-old woman was admitted to our department with epigastric discomfort and nausea over the duration of 1 month. An esophagogastroduodenoscopy showed the presence of a 1.0×1.0 cm-sized flat lesion with central ulceration at the greater curvature side of the antrum. A biopsy demonstrated the presence of an adenocarcinoma of well differentiated, intestinal type in the stomach. Endoscopic submucosal dissection was done and the diagnosis of a composite neuroendocrine carcinoma with an adenocarcinoma of the stomach was confirmed. We report a case of a gastric composite tumor with an adenocarcinoma and neuroendocrine carcinoma confirmed by endoscopic submucosal dissection with a review of the literature.

Composite neuroendocrine carcinoma with adenocarcinoma of the stomach misdiagnosed as a giant submucosal tumor

A composite glandular/exocrine-endocrine carcinoma of the gastrointestinal tract is characterized by the co-existence of two adjacent, but histologically-distinct tumors in an organ. Composite glandular/exocrine-endocrine carcinomas are a special type of tumor comprised of common adenocarcinomas and neuroendocrine components that account for at least one-third of the entire tumor area. Composite tumors have been reported in a range of organs, but are relatively rare in the stomach. We report a case of a composite neuroendocrine carcinoma with an adenocarcinoma of the stomach (mixed exocrine-endocrine carcinoma), which was misdiagnosed as a giant submucosal tumor preoperatively based on esophagogastroduodenoscopy and a contrast-enhanced axial computed tomographic scan.