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Hematology/Oncology

Omayra Reyes Santiago, MD

Works at hospitals in Cayey, PR · Puerto Rico

Summary

Dr. Omayra Reyes Santiago, MD is a hematologist-oncologist at Hc 73 Box, Suite 6440, Cayey, PR 00736. Phone: (787) 520-7211. Accepts Medicare assignment. In 2024, Omayra Reyes Santiago had 23 Original Medicare patients and 2,914 services. NPI 1124287313. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Hematologist-oncologist (Medicare lists Hematology/Oncology)
  • Address: Hc 73 Box, Suite 6440, Cayey, PR 00736 · Directions
  • Phone: (787) 520‑7211
  • Medicare: Accepts Medicare assignment
  • Hospital: Hospital Menonita de Cayey
  • Medical school: graduated 2006 (20 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Omayra Reyes Santiago, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Omayra Reyes Santiago accept Medicare assignment?
Yes. Medicare's clinician data says Omayra Reyes Santiago accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Omayra Reyes Santiago see?
In 2024, CMS data shows 23 Original Medicare patients and 2,914 services for Omayra Reyes Santiago. This counts Original Medicare only and measures volume, not quality.
What is Omayra Reyes Santiago's NPI number?
1124287313. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Omayra Reyes Santiago, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients23
Services billed to Medicare2,914
Different services or procedures27
Participating Medicare providerYes
Average age of these patients76

Most frequent services

  1. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)67 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Diabetes48%

Hospitals where Omayra Reyes Santiago works

Medicare's Facility Affiliation Data lists Omayra Reyes Santiago at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Omayra Reyes Santiago is enrolled with Medicare (CMS data updated October 2, 2026).

Specialties

Find other Hematology/Oncology doctors in Puerto Rico →

Other hematologist-oncologists in Puerto Rico

Clinicians with the same Medicare primary specialty in Puerto Rico — not a recommendation.

All hematologist-oncologists in Puerto Rico →

Clinician information

CredentialMD
Graduation year2006 (20 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1124287313
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians