N. Paul Ohori, MD
Professor of Pathology

Dr. Ohori is Medical Director of Cytopathology, UPMC Presbyterian.

Office Location:
Department of Pathology
Rm. A610
UPMC Presbyterian
200 Lothrop Street
Pittsburgh, PA 15213
Contact Information:
Office Telephone: 412-647-9843
Fax: 412-647-3455
Email: ohorinp@upmc.edu


  • BA - Johns Hopkins University, 1983
  • MD - Medical College of Virginia, 1987

Clinical Expertise

Dr. Ohori is a Professor of Pathology in the Division of Anatomic Pathology and Medical Director of Cytopathology at UPMC Presbyterian. He has been a faculty member in the School of Medicine since 1992 and has been involved in medical student, cytotechnology student, resident, and fellow training. He has been the chair of the curriculum committee of the residency program in the Department of Pathology, Board Member of the School of Cytotechnology, and the cytopathology representative to the Molecular Anatomic Pathology Division. From 2001 to 2008, he served as the Director for the Cytopathology Fellowship Program.

Dr. Ohori has provided service to the UPMC system since 1992 and over the last 15 years, he has served as the Medical Director of Cytopathology at UPMC Presbyterian Hospital. His service responsibilities have focused on Non-Gynecologic Cytopathology and Thoracic Surgical Pathology. In this regard, he provides consultative expertise in thyroid, head and neck, pulmonary, and gastrointestinal cytopathology. Dr. Ohori participates in a number of regional and national conferences in the areas of thyroid cytopathology and thoracic pathology.

Research Expertise

Dr. Ohori has focused his efforts in clinically related research in Non-gynecologic Cytopathology. In general, his research involves three main areas: 1. bridging the gap between cytopathology and surgical pathology by emphasizing correlation and understanding of organ specific concepts 2. applying ancillary technologies to refine diagnostic and pathogenetic information, and 3. quality improvement in cytopathology laboratory performance. Specifically, he has investigated the cytologic and molecular manifestations of thyroid, pancreaticobiliary and pulmonary neoplasms. Furthermore, he has been involved in improving cytopathology laboratory performance by developing a systematic method for cytologic-histologic correlation in non-gynecologic cytopathology.


Non-gynecologic Cytopathology and Pulmonary Pathology

Selected Publications

View Dr. Ohori's publications on PubMed

  • Ohori NP, Nikiforova MN, Schoedel KE, LeBeau SO, Hodak SP, Seethala RR, Carty SE, Ogilvie JB, Yip L, Nikiforov YE. Contribution of molecular testing to thyroid fine-needle aspiration cytology of "follicular lesion of undetermined significance/atypia of undetermined significance". Cancer (Cancer Cytopathol) 118:17-23, 2010.
  • Ocque R, Tochigi N, Ohori NP, Dacic S. Utility of immunohistochemistry and histochemistry in the classification of lung adenocarcinoma and squamous cell carcinoma in cytology specimens. Am J Clin Pathol. 136:81-7, 2011.
  • Marks-Jones DA, Sutkowski BA, Schoedel KE, Ohori NP. Selective screening for nongynecologic cytology specimens: Modifying the screening process for improved efficiency and practice. Diagn Cytopathol. 39:717-22, 2011.
  • Nikiforov YE, Ohori NP, Hodak SP, Carty SE, LeBeau SO, Ferris RL, Yip L, Seethala RR, Tublin ME, Stang MT, Coyne C, Johnson JT, Stewart AF, Nikiforova MN. Impact of mutational testing on the diagnosis and management of patients with cytologically indeterminate thyroid nodules: a prospective analysis of 1056 FNA samples. J Clin Endocrinol Metab. 96:3390-7, 2011.
  • Ohori NP, Schoedel KE. Variability in the atypia of undetermined significance/follicular lesion of undetermined significance diagnosis in the Bethesda system for reporting thyroid cytopathology: sources and recommendations. Acta Cytol. 55:492-8, 2011.
  • Tochigi N, Dacic S, Ohori NP. Bronchoscopic and transthoracic cytology and biopsy for pulmonary nonsmall cell carcinomas: performance characteristics by procedure and tumor type. Diagn Cytopathol. 40:659-663, 2012.
  • McCoy KL, Carty SE, Armstrong MJ, Seethala RR, Ohori NP, Kabaker AS, Stang MT, Hodak SP, Nikiforov YE, Yip L. Intraoperative Pathologic Examination in the Era of Molecular Testing for Differentiated Thyroid Cancer. J Am Coll Surg. 215:546-54, 2012.
  • Ohori NP, Singhal R, Nikiforova MN, Yip L, Schoedel KE, Coyne C, McCoy KL, LeBeau SO, Hodak SP, Carty SE, Nikiforov YE. BRAF mutation detection in indeterminate thyroid cytology specimens: underlying cytologic, molecular, and pathologic characteristics of papillary thyroid carcinoma. Cancer (Cancer Cytopathol) 121:197-205, 2013.
  • Gupta N, Dasyam AK, Carty SE, Nikiforova MN, Ohori NP, Armstrong M, Yip L, LeBeau SO, McCoy KL, Coyne C, Stang MT, Johnson J, Ferris RL, Seethala R, Nikiforov YE, Hodak, SP. RAS mutations in thyroid FNA specimens are highly predictive of predominantly low risk follicular-pattern cancers. J Clin Endocrinol Metab J Clin Endocrinol Metab. 2013;98(5):E914-22.
  • Nikiforova MN, Khalid A, Fasanella KE, McGrath KM, Brand RE, Chennat JS, Slivka A, Zeh HJ, Zureikat AH, Krasinskas AM, Ohori NP, Schoedel KE, Navina S, Mantha GS, Pai RK, Singhi AD. Integration of KRAS testing in the diagnosis of pancreatic cystic lesions: a clinical experience of 618 pancreatic cysts. Mod Pathol. 2013;26(11):1478-87.
  • Heller M, Gilbert C, Ohori NP, Tublin M. Correlation of ultrasound findings with the Bethesda cytopathology classification for thyroid nodule fine needle aspiration: a pathology-radiology primer for radiologists. AJR Am J Roentgenol 2013;201:W487-94.
  • Mehta RS, Carty SE, Ohori NP, Hodak SP, Coyne C, LeBeau SO, Tublin ME, Stang MT, Johnson JT, McCoy KL, Nikiforova MN, Nikiforov YE, Yip L. Nodule size is an independent predictor of malignancy in mutation-negative nodules with "follicular lesion of undetermined significance" cytology. Surgery. 2013;154:730-6.
  • Ohori NP, Wolfe J, Hodak SP, LeBeau SO, Yip L, Carty SE, Duvvuri U, Schoedel KE, Nikiforova MN, Nikiforov YE. "Colloid-Rich" follicular neoplasm/suspicious for follicular neoplasm thyroid fine-needle aspiration specimens: Cytologic, histologic, and molecular basis for considering an alternate view. Cancer Cytopathol. 2013;121:718-28.
  • Wharry LI, McCoy KL, Stang MT, Armstrong MJ, LeBeau SO, Tublin ME, Sholosh B, Silberman A, Ohori NP, Nikiforov YE, Hodak SP, Carty SE, Yip L. Large Thyroid Nodules (≥ 4 cm): Can Ultrasound and Cytology Reliably Exclude Cancer? World J Surg. 2014;38:614-21.
  • Yip L, Wharry LI, Armstrong MJ, Silberman A, McCoy KL, Stang MT, Ohori NP, LeBeau SO, Coyne C, Nikiforova MN, Bauman JE, Johnson JT, Tublin ME, Hodak SP, Nikiforov YE, Carty SE. A Clinical Algorithm for Fine-Needle Aspiration Molecular Testing Effectively Guides the Appropriate Extent of Initial Thyroidectomy. Ann Surg. 2014;260:163-8.
  • Armstrong MJ, Yang H, Yip L, Ohori NP, McCoy KL, Stang MT, Hodak SP, Nikiforova MN, Carty SE, Nikiforov YE. PAX8/PPARγ rearrangement in thyroid nodules predicts follicular-pattern carcinomas, in particular the encapsulated follicular variant of papillary carcinoma. Thyroid. 2014;24:1369-74.
  • Singhi AD, Nikiforova MN, Fasanella KE, McGrath KM, Pai RK, Ohori NP, Bartholow TL, Brand RE, Chennat JS, Lu X, Papachristou GI, Slivka A, Zeh HJ, Zureikat AH, Lee KK, Tsung A, Mantha GS, Khalid A. Preoperative GNAS and KRAS Testing in the Diagnosis of Pancreatic Mucinous Cysts. Clin Cancer Res. 2014;20:4381-9.
  • Radkay LA, Chiosea SI, Seethala RR, Hodak SP, LeBeau SO, Yip L, McCoy KL, Carty SE, Schoedel KE, Nikiforova MN, Nikiforov YE, Ohori NP. Thyroid nodules with KRAS mutations are different from nodules with NRAS and HRAS mutations with regard to cytopathologic and histopathologic outcome characteristics. Cancer Cytopathol. 2014;122:873-82.
  • Nikiforov YE, Carty SE, Chiosea SI, Coyne C, Duvvuri U, Ferris RL, Gooding WE, Hodak SP, LeBeau SO, Ohori NP, Seethala RR, Tublin ME, Yip L, Nikiforova MN. Highly accurate diagnosis of cancer in thyroid nodules with follicular neoplasm/suspicious for a follicular neoplasm cytology by ThyroSeq v2 next-generation sequencing assay. Cancer. 2014;120:3627-34.
  • Schneider F, Smith M, Lane M, Pantanowitz L, Dacic S, Ohori NP. Adequacy of core needle biopsies and fine needle aspirates for molecular testing of lung adenocarcinomas. Am J Clin Pathol. 2015;143:193-200.