A Rare Case of Primary Endometrial Hepatoid Adenocarcinoma on 18F-FDG PET/CT

FDG PET/CT in Staging of α-Fetoprotein-Producing Hepatoid Adenocarcinoma of the Pancreas

ABSTRACT

Hepatoid adenocarcinoma of the pancreas is a rare aggressive tumor with poor prognosis. We describe contrast-enhanced CT and FDG PET/CT findings in a case of pancreatic hepatoid adenocarcinoma with significantly elevated α-fetoprotein level presenting as acute pancreatitis. The primary pancreatic tumor diffusely involved the pancreas and showed heterogeneous enhancement mimicking acute necrotizing pancreatitis on contrast-enhanced CT. FDG PET/CT showed intense FDG uptake (SUV max , 24.5) of the left supraclavicular and retroperitoneal lymph node metastases, suggesting FDG PET/CT may be useful for staging of this aggressive tumor.

Disseminated Primary Uterine Hepatoid Adenocarcinoma with α-Fetoprotein Production Demonstrated on 18F-FDG PET/CT

We present the 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) findings in a 57-year-old woman with post-menopausal bleeding diagnosed with hepatoid adenocarcinoma (HAC) with a primary tumour in the uterine corpus and a highly elevated level of serum-α-fetoprotein (S-AFP) at presentation. HAC is a variant of adenocarcinoma with hepatic differentiation representing a heterogeneous group of neoplasms that morphologically and immunphenotypically resemble hepatocellular carcinoma (HCC) but are of extrahepatic origin. Microscopically, they are usually poorly differentiated adenocarcinomas proliferating in solid sheets or in a trabecular or cord-like arrangement. Primary uterine HAC is exceedingly rare with a general poor prognosis, and data is sparse and limited to case reports, making the clinical management challenging. Various primary anatomical sites have been reported in the literature, with the stomach being the most common primary site. 18F-FDG PET/CT plays an important role in staging and follow-up in many gynecological malignancies including uterine corpus cancer. To the best of our knowledge, this is the first report describing a primary uterine hepatoid adenocarcinoma with metastases to bone, vagina and lymph nodes on 18F-FDG PET/CT. By utilizing the ability of PET to detect early metabolic changes prior to visible structural changes on conventional imaging, this case illustrates a potential role of 18FDG-PET/CT in the staging of primary endometrial HAC by depicting distant metastasis that is not readily identifiable on CT alone.

Primary Hepatoid Adenocarcinoma of the Lung: A Systematic Literature Review

Background

Hepatoid adenocarcinoma (HAC) of the lung (HAL) is a rare and aggressive extrahepatic adenocarcinoma with an unknown etiology and unfavorable prognosis, which is similar to the pathophysiological characteristics of hepatocellular carcinoma (HCC).

Methods

We first presented a 67-year-old patient diagnosed with HAC in the right middle lobe of the lung. Then, a systematic literature search was performed for HAL cases recorded between 1990 and 2020 based on three databases. The clinicopathological features, therapeutic method, and prognosis of this rare disease were reviewed, and corresponding prognostic factors were explored using Kaplan–Meier (K-M) curve and Cox proportional hazards regression model. Additionally, the potential biological mechanisms of HAL were further explored and compared with HCC and lung adenocarcinoma (LUAD) based on online databases.

Results

In the present study, we reported an HAL patient who underwent surgical resection combined with chemotherapy and succumbed to disease 13 months after surgery. Additionally, a total of 43 experimental studies with 49 HAL patients, including the present case, met the inclusion criteria and were included in the present review. We found that HAL is characterized by a male-dominated incidence and is more common in the right lung. Patients in the surgical subgroup have a better prognosis than those in the non-surgical subgroup (p = 0.034). Moreover, the Cox proportional hazards regression model demonstrated that surgical resection can significantly improve the prognosis of HAL patients (p = 0.016). HAL is a rare disease associated with gene mutations that has a distinctive cause and unique pathogenesis. Additionally, Afatinib and Gefitinib may be new effective agents to better combat HAL.

Conclusion

In conclusion, males may exhibit an increased risk of developing HAL and poorer prognosis than females. Surgical resection combined with chemotherapy may prolong the survival of patients with HAL. HAL has its unique clinicopathological characteristics and biological mechanisms.

α-Fetoprotein-Producing Endometrial Carcinoma Is Associated With Fetal Gut-Like and/or Hepatoid Morphology, Lymphovascular Infiltration, TP53 Abnormalities, and Poor Prognosis: Five Cases and Literature Review

The clinicopathological, immunohistochemical, and molecular characteristics of α-fetoprotein (AFP)-producing endometrial carcinoma (AFP+ EC) are poorly understood. From 284 cases of endometrial carcinoma in our pathology archive, we identified five cases (1.8%) of AFP+ EC with fetal gut–like (4/5) and/or hepatoid (2/5) morphology. All cases exhibited lymphovascular infiltration. In addition, 24 cases of endometrial carcinoma with elevated serum AFP levels were retrieved from the literature. The patient age ranged from 44 to 86 years (median: 63). Of 26 cases whose FIGO (International Federation of Gynecology and Obstetrics) stage and follow-up information was available (mean follow-up 24 months), 15 were stage I or II and 11 were stage III or IV. Even in stage I or II disease, death or relapse occurred in more than half of the patients (8/15). Detailed analysis of our five cases revealed that, on immunohistochemistry, AFP+ EC was positive for SALL4 (4/5), AFP (3/5), and HNF1β (4/5) in >50% of neoplastic cells and negative for estrogen and progesterone receptors (5/5), PAX8 (4/5), and napsin A (5/5). Four cases exhibited aberrant p53 immunohistochemistry and were confirmed to harbor TP53 mutations by direct sequencing. No mutation was found in POLE, CTNNB1, or KRAS. In conclusion, AFP+ EC merits recognition as a distinct subtype of endometrial carcinoma, which occurs in 1.8% of endometrial carcinoma cases, are associated with TP53 abnormalities, exhibit lymphovascular infiltration, and can show distant metastasis even when treated in early stage.

FDG PET/CT of Hepatoid Adenocarcinoma of the Gallbladder

Primary hepatoid adenocarcinoma of the gallbladder is rare. A 67-year-old woman presented with right upper quadrant abdominal pain with elevated α-fetoprotein level. Abdominal ultrasound and MRI showed a tumor in the gallbladder with normal liver. FDG PET/CT showed increased FDG uptake of the gallbladder tumor with retroperitoneal lymph node metastasis. Cholecystectomy was performed. Primary hepatoid adenocarcinoma of the gallbladder was confirmed by histopathology.