Case: Misdiagnosed Epidermoid Cyst on the Back
for 6 Years – Cured by Punch Excision
Hello, this is Dr. Kohrita,
director of Kohrita Hiro Orthopedic and Plastic Surgery Clinic
in Shin-Osaka, Yodogawa-ku, Osaka.
▶ See more actual case reports of epidermoid cyst surgeries
This time, I will present the case of a woman in her 40s who suffered
for 6 years because her back lump was repeatedly misdiagnosed
as “not an epidermoid cyst.”
After undergoing surgery at our clinic, she was completely cured
with an excellent cosmetic result.
🔍 A Back Lump Misdiagnosed as
“Not an Epidermoid Cyst” for 6 Years
The patient, a woman in her 40s,
noticed a lump on her back about 6 years earlier.
She regularly visited a nearby dermatology clinic.
However, each time she was told:
“This is not an epidermoid cyst.”
As a treatment, the doctor only removed the contents
of the lump with tweezers, without removing the cyst wall.
As a result, even after 6 years, the lump persisted without improvement.
💻 Searching Online and Visiting Our Clinic:
“This is Clearly an Epidermoid Cyst”
Frustrated by the lack of progress,
the patient searched online and came across our case reports.
She then visited our clinic.
Upon examination, I immediately told her:
“This is clearly an epidermoid cyst (atheroma).”
She strongly agreed, saying
“That’s exactly what I thought,”and was very upset to learn
she had endured 6 years of misdiagnosis and inadequate treatment.
🩺 Surgery with Punch Excision:
Capsule Completely Removed
At our clinic, we performed surgery using the punch excision method.
Through a small incision,
the cyst and its capsule were completely and carefully removed,
with minimal bleeding.
💧 Postoperative Care with Natsui-style Moist Wound Healing
– No Antibiotics or Disinfection
The wound was managed with Natsui-style moist wound healing:
-
No disinfection at all
-
No antibiotics prescribed
-
Showering and bathing allowed immediately after surgery
The wound healed smoothly without infection or complications.
📸 Three Years Later: Scar Barely Visible
About 3 years after surgery,
the patient returned to our clinic for an unrelated issue.
When we checked the surgical site, the scar was barely visible.
She kindly allowed us to take follow-up photos and happily said:
“I’m so glad it healed so beautifully.”
✅ Summary: A Long-standing Lump May Actually
Be an Epidermoid Cyst
-
Misdiagnosed for 6 years as “not an epidermoid cyst”
-
Actually an epidermoid cyst (atheroma), completely cured by punch excision
-
Postoperative care with moist wound healing
→ no disinfection, no antibiotics, minimal scarring
Even after 3 years, the surgical site remained beautifully healed
Back epidermoid cyst that was misdiagnosed and untreated for 6 years (preoperative view)
Intraoperative photo of a back epidermoid cyst. The cyst contents are being carefully extracted.
Capsule of an epidermoid cyst being removed from the back during punch excision surgery. Treated postoperatively with the Natsui moist healing method.
Postoperative photo immediately after punch excision of a back epidermoid cyst. Bleeding was minimal.
Back atheroma excised specimen. Both the contents and the capsule were cleanly removed.
Back atheroma postoperative day 1: no pain and minimal swelling.
Back atheroma postoperative day 4: no swelling, no pain, no infection.
Back atheroma postoperative day 9: no pain, no swelling, no infection, wound depth improving.
Back atheroma postoperative day 16: no pain, no swelling, no infection, wound nearly healed.
Back atheroma, 3 years postoperative. The scar is almost invisible, with excellent healing.
About Our Clinic
At our clinic (Shin-Osaka, Yodogawa-ku, Osaka City),
we specialize in day-surgery for epidermoid cysts (atheromas)
using punch excision,
combined with Natsui-style moist wound healing to minimize scarring.
-
We also treat inflamed or recurrent cysts that other clinics may refuse.
-
Postoperatively, patients can bathe freely, with no gauze,
no disinfection, and no antibiotics required. -
Pain, swelling, and downtime are kept to a minimum.
▶ Visit the official website of Kohrita Hiro Orthopedic and Plastic Surgery Clinic
🔵 Frequently Asked Questions (FAQ) About Epidermoid Cysts
Q1. What is an epidermoid cyst (atheroma)?
A benign tumor under the skin, containing keratin and sebum.
It rarely disappears spontaneously.
If left untreated, it may cause swelling, pain, or infection.
Q2. Do epidermoid cysts heal naturally?
No. Even if they shrink temporarily,
the capsule remains and recurrence is common.
Complete removal is required.
Q3. Can surgery be done during inflammation?
Yes. At our clinic, we can operate with punch excision
even if the cyst is inflamed. Surgery actually speeds recovery.
Q4. Can antibiotics cure an inflamed epidermoid cyst?
No. Because the cyst wall has no blood supply,
antibiotics cannot reach the infection.
Only complete surgical removal is effective.
Q5. What is the surgical method?
We use the punch excision method –
removing the cyst and its capsule through a small hole.
Minimal pain and minimal scarring.
Q6. How is postoperative care done?
We use moist wound healing (Natsui method):
-
No disinfection
-
No gauze
-
Shower/bath from the next day
-
No routine antibiotics
Q7. Is recurrence common?
If the capsule is completely removed,
recurrence is very rare. We carefully ensure full removal.
Q8. How much pain or swelling occurs after surgery?
Most patients say: “It hurt far less than I expected.”
Even with inflammation, postoperative pain is usually minimal.
Q9. Should small cysts be removed early?
Yes. Earlier surgery means smaller scars, faster healing, and easier recovery.
Q10. Is surgery covered by health insurance?
Yes. Epidermoid cyst removal is covered
under the Japanese national health insurance system.
▶ See more case reports of epidermoid cyst surgeries
Message from the Director
All articles on this blog are written personally by me, the director.
We never use SEO agencies or paid reviews.
All content is based on actual cases at our clinic.
Currently, nearly 3,000 people read our blog every month.
Many patients find it helpful when considering treatment.
We will continue to provide honest and reliable information.
Please feel free to use this blog as a reference.
Please note that English is not my first language,
so there may be some expressions that are not perfectly natural.
Thank you for your understanding.
