The Past, Present, and Future Statuses of Formerly Classified “Atypical Pituitary Adenomas”: A Clinicopathological Assessment of 101 Cases in a Cohort of More than 1,000 Pure Endoscopically Treated Patients in Single Center

Aim This study was aimed to assess the clinical aggressiveness of pituitary neoplasms that were previously defined as atypical adenomas. Methods A total of 1,042 pituitary adenomas were included in the study and 101 of them were diagnosed as atypical adenoma. Demographic characteristics, radiological evaluations, and clinical information were obtained from a computer-based patient database. Cases were categorized as atypical or typical using the criteria listed in 2004 Classification of Tumors of Endocrine Organs. Results The cure and reoperation rates did not show any statistically significant difference between the typical and atypical adenomas. However, a higher Ki-67 labeling index was found to be associated with a higher rate of reoperation (p = 0.008) in atypical adenomas. Of note, cavernous sinus invasion or parasellar extension was found to be associated with lower cure rates in patients with atypical pituitary adenomas (p < 0.001 and p = 0.001, respectively). Conclusion Although atypical pituitary adenomas are known to be more invasive, this study demonstrated that the reoperation and cure rates are the same for typical and atypical adenomas. Our findings advocate for omitting the use of atypical adenoma terminology based solely on pathological evaluation. As stated in the 4th edition of the World Health Organization (WHO) classification, accurate tumor subtyping, evaluation of proliferation by means of mitotic count and Ki-67 labeling index, and radiological and intraoperative assessments of tumor invasion should be taken into consideration in the management of such neoplasms.

Atypical parathyroid adenoma with clinically aggressive course of hyperparathyroidism: clinical case report

Primary hyperparathyroidism is common clinical endocrine disorder with a prevalence between 1–2%. Solitary parathyroid adenomas account from 80 to 85% of cases of PHPT, hyperplasia and multiple adenomas is up to 15%, parathyroid carcinoma is a very rare cause of PHPT, accounting for about a 1% of cases. Clinically aggressive and atypical adenomas should be separately noted because of severe clinical course and life-threatening hypercalcemia, high morbidity and mortality, unknown malignant potential. No definite criteria are considered to be present to distinguish preoperatively atypical adenoma from parathyroid typical adenoma or carcinoma. The clinical course of the disease remains the only tool that allows to suspect an aggressive tumor on the preoperative stage. We present the clinical case of a 61-year-old female patient with a clinically “aggressive” course of PHPT and severe metabolic disturbances of bone tissue due to the atypical adenoma of the parathyroid gland.