CION Ameerpet
Pancreatic Cancer · Neuroendocrine Tumours · Reviewed by CION Oncologists
Insulinoma — the pancreatic tumour that causes low blood sugar
An insulinoma is a small tumour in the pancreas that makes insulin without being asked to, so blood sugar drops when you have not eaten. Most are benign and curable. The difficulty is almost always how long it takes for anyone to think of it.
- Most are benign and single — the usual outcome after the tumour is removed is a complete cure.
- The timing is the clue — episodes come with fasting or exertion and settle within minutes of eating.
- Blood tests come before scans — a sample taken during an episode is worth more than any image.
- Often called something else first — anxiety, epilepsy or a psychiatric problem, for months or longer.
17+
Cancer Specialists
on Panel
on Panel
35+
Centres Across
Telangana & AP
Telangana & AP
15,000+
Patients
Treated
Treated
4.8★
Google Rating
(800+ reviews)
(800+ reviews)
Start here
What an Insulinoma Actually Is
An insulinoma is a small tumour that grows in the hormone-producing cells of the pancreas and makes insulin on its own schedule. It ignores the signal that would normally switch insulin off as blood sugar falls. That single fact explains every symptom on this page. It belongs to the family of pancreatic neuroendocrine tumours, and it is the commonest of the functioning ones — the group that causes trouble by releasing a hormone rather than by growing large.
Two things are worth knowing before anything else. Most insulinomas are small, single, and confined to the pancreas. And most are not cancerous: the great majority behave in a benign way and are cured completely once the tumour is removed. That is a genuinely different situation from ductal adenocarcinoma, the common and far more aggressive pancreatic cancer that most online reading is about. If you have arrived here after searching for a low blood sugar tumour, that distinction is the most important thing to take away from this page.
The hard part is usually not the treatment. It is the delay before anyone thinks of the diagnosis. Because the tumour releases insulin in episodes, symptoms come and go, and they look like a great many commoner things — a panic attack, epilepsy, a psychiatric problem, ordinary hunger, or a reaction to a diabetes tablet. People are often investigated along those lines first, sometimes for a long time. Understanding the pattern is what shortens that delay. Where an insulinoma sits within the wider group, and how it differs from the tumours that make no hormone at all, is set out in functioning versus non-functioning pancreatic neuroendocrine tumours.
Did you know? The rule that decides whether low blood sugar is investigated at all is older than any scan. It is called Whipple’s triad: symptoms of hypoglycaemia, a genuinely low blood glucose measured at the moment those symptoms are present, and relief of the symptoms once the glucose is raised. Endocrine Society clinical practice guidance on hypoglycaemia in adults, and the NCCN guideline covering neuroendocrine tumours, both build on that same order — biochemistry first, finding the tumour second. It is the reason a specialist may want blood taken during an episode, or a supervised fast under observation, rather than sending you straight for a scan. Imaging cannot tell you whether a small spot on the pancreas is the thing making you unwell. A blood sample drawn while you feel unwell very often can.
What it actually feels like
The Insulinoma Symptom Pattern
Insulinoma symptoms are not one thing. They arrive in two distinct families, and it is the timing — not the severity — that usually gives the diagnosis away.
Adrenaline symptoms
Sweating, shaking, palpitations, hunger
As glucose falls, the body releases adrenaline to pull it back up. Sweating, trembling, a racing heart, sudden anxiety and fierce hunger follow. These are the warning symptoms, and they are frequently read as a panic attack.
Brain symptoms
Confusion, odd behaviour, blurred vision
The brain runs on glucose. When it runs short, thinking slows, vision blurs, speech changes and behaviour can go out of character. A severe episode can cause a seizure or loss of consciousness. Family usually notice these before the person does.
Timing
Episodes when fasting or after exertion
The classic pattern is symptoms before breakfast, during a long gap between meals, or after exercise — and relief within minutes of eating something sweet. Timing tied to fasting is the single most useful clue there is.
Eating to stay well
Constant snacking, night eating, weight gain
Many people work out for themselves that food stops the episodes, and start eating frequently, including through the night. Weight gain in someone who otherwise feels unwell is a recognised and easily missed clue.
Duration
Months or years of feeling unwell
Because episodes come and go and settle with food, an insulinoma is often present for a long time before anyone names it. A long history is not evidence that the tumour is aggressive — usually the opposite.
Not a diabetes low
No diabetes treatment to explain it
Low blood sugar in someone taking treatment for diabetes usually has an obvious cause. Repeated, documented lows in someone on no such treatment is the situation that genuinely needs explaining.
Why the diagnosis is late
What an Insulinoma Gets Called First
Almost everyone with an insulinoma is given another explanation before the right one. None of these first answers is stupid — each fits part of the picture. What separates them is what a blood sample taken during an episode shows.
| Called first | Why the confusion happens | What sets an insulinoma apart |
|---|---|---|
| Panic or anxiety disorder | Sweating, tremor, palpitations and a sense of dread are shared by both, and both come in episodes that pass. | Episodes cluster around fasting and exertion, and settle with food rather than with rest or reassurance. |
| Epilepsy or a seizure disorder | A deep episode can cause a genuine seizure, so the label often follows the first event witnessed. | Blood glucose is low at the time of the event, and anti-seizure treatment does not stop the episodes. |
| A psychiatric or behavioural problem | Confusion, irritability and out-of-character behaviour are what family report, so the referral goes that way. | The behaviour is time-locked to hunger and reverses completely once glucose is restored. |
| Dementia or cognitive decline | In an older adult, repeated confusion and memory lapses are easily attributed to age. | Cognition is entirely normal between episodes, and the lapses track missed meals. |
| Diabetes treatment side effect | Hypoglycaemia is a familiar complication of treatment, so a known diabetic is assumed to be over-treated. | Episodes continue after treatment is reduced or stopped, and the body’s own insulin markers stay inappropriately high. |
| Simply not eating enough | Faintness and shakiness on an empty stomach is universal, so it is dismissed as a missed meal. | A healthy pancreas switches insulin off during a fast. In an insulinoma it keeps going, and the glucose keeps falling. |
A prompt, not a diagnosis
When Low Blood Sugar Is Worth Properly Investigating
Low blood sugar is common and almost never caused by a tumour. Read these as the situations where measuring a glucose during an episode changes what happens next, rather than as a list of warning signs.
- The episodes come when you have not eaten — first thing in the morning, on a long gap between meals, or after exercise — and food reliably ends them.
- Someone has watched you become confused, slurred or out of character, and it passed after you ate. What a witness describes is often more useful than what you remember.
- You have started carrying sweets, or eating at night, to head the episodes off. Rearranging your life around food is a symptom in its own right.
- You have gained weight you cannot account for while feeling steadily less well. It runs against what people expect, which is exactly why it gets missed.
- A blood sugar has actually been measured as low during an episode and nobody has explained why — and you take no treatment for diabetes.
- Hormone-producing tumours run in your family — in the parathyroid or pituitary glands as well as the pancreas — or a MEN1 change is already known in a relative.
- You are being treated for anxiety or epilepsy and it is not working. Treatment that does not touch the episodes is a reason to re-open the question, not to increase the dose.
What we will not do: tell you that one low reading means a tumour, or send you for scans to settle an anxiety that a blood test and a conversation can settle properly. Book a free consultation or call 1800 202 8726.
12+ Centres in Hyderabad · Pick yours
CION cancer care is closer than you think.
We're never more than 30 minutes away. Same panel of specialists at every centre. Same tumour board reviews. Same NCCN protocols. Pick the closest one and call directly — or let us pick for you.
CION Ameerpet
CION Kukatpally
CION L.B. Nagar
CION Tolichowki
CION Masab Tank
CION Banjara Hills
CION Kompally
CION Balanagar
CION Siddipet
CION Sangareddy
Not sure which centre fits best? Tell us where you are — we'll suggest the closest one with the right specialists.
Help me pick the right centre
Beyond Hyderabad
35+ centres across Telangana & Andhra Pradesh
Travelling for treatment? We may have a centre right where you are.
Telangana
Andhra Pradesh
Don't see your city? Call 18002028726 — we'll find your nearest CION partner centre.
Meet the Specialists
17+ senior cancer specialists. One panel for your case.
Trained at AIIMS, Tata Memorial, and leading international centres. Combined 150+ years of experience. Every complex case is reviewed by 3+ of them — together.
Medical Oncologist
Medical Oncologist
Dr. C. Raghavendra Reddy
MBBS(Gold Medal), DNB(General Medicine), DM(Medical Oncology)(Gold Medal)
Medical Oncologist
Dr. Bharati Devi Gorantla
MBBS, MD(General Medicine), DM(Medical Oncology)(Adyar,Chennai), ECMO, MRCP SCE(UK)
Medical Oncologist
Dr. Owais Mohammed
MBBS, MD (General Medicine), DrNB (Medical Oncology), ECMO, MRCP SCE (Medical Oncology) (UK)
Medical Oncologist
Medical Oncologist
Surgical Oncologist
Dr. Muralidhar Muddusetty
MBBS (AIIMS), MS (Surgery) (AIIMS), DNB (Surgical Oncology), MRCS (Edinburgh)
Surgical Oncologist
Surgical Oncologist
Surgical Oncologist
Dr. Vinay Mamidala
MBBS, MS(General Surgery), M.Ch(Surgical Oncology), FMAS, FARIS(Ongoing)
Surgical Oncologist
Radiation Oncologist
Radiation Oncologist
Radiation Oncologist
Hematologist
Interventional Radiologist
Dr. Mohammed Imran
Surgical Oncologist
Dr. Vajja Sandeep Kumar
MBBS, MS (General Surgery), DrNB (Surgical Oncology), FALS Oncology
Surgical Oncologist
Want a specific doctor for your case? Mention them when booking.
Book Free ConsultationBook an appointment with our specialist
Share your name and number — we'll call you back within 30 minutes to schedule your consultation.
A Blood Test During an Episode Answers More Than a Scan
Getting the order right is what shortens the years people spend without an explanation.
What actually happens
How an Insulinoma Is Confirmed, and Then Treated
-
Capture the episode in a blood sample
Glucose, insulin, C-peptide, proinsulin and ketone bodies are measured on the same sample, taken while you are symptomatic. Insulin that stays switched on while glucose is falling is the finding the whole diagnosis rests on.
Ordered and reported in-house at CION -
A supervised fast, if the episodes will not come to order
Where no episode can be captured in ordinary life, a fast is carried out under close observation with regular sampling, and is stopped the moment symptoms appear with a low glucose. It is monitored throughout and is not something to attempt at home.
Arranged with your physician team; bloods reported in-house -
Prove the insulin is being made inside you
C-peptide and proinsulin separate insulin the body has made itself from insulin that has been injected, and a screen excludes tablets that push the pancreas to release insulin. This step protects you from an operation for the wrong reason.
In-house at CION -
Only then, find the tumour
A pancreatic-protocol contrast CT and an MRI come first. Insulinomas are often small, so a normal scan does not close the question — endoscopic ultrasound is frequently what finds them, and functional PET imaging is used in selected cases.
CT and MRI in-house at CION; EUS and PET-CT or DOTATATE PET coordinated with partner centres and may be billed there -
Keep you safe while the plan is made
Frequent carbohydrate-containing meals, a written overnight plan and, where the episodes are severe, a drug class that suppresses insulin release from the tumour hold the ground until definitive treatment. Nutrition support is part of this, not an afterthought.
Medical, nutrition and supportive care in-house at CION -
Removal, which usually ends the problem for good
Most insulinomas are treated by shelling the tumour out or by a limited pancreatic resection, and for a benign, single tumour that is normally the end of it. The wider picture, including what happens when an operation is not the right answer, is set out in how pancreatic neuroendocrine tumours are treated.
Coordinated with specialist HPB surgical partners and may be billed there
Plainly stated
What CION Delivers, and What Is Coordinated
Saying this early saves an awkward conversation later. Your first consultation is free and lasts 45 minutes, and it is a genuine review of your reports and your symptom diary rather than a booking appointment.
Delivered in-house at CION, across 35+ centres in Telangana and Andhra Pradesh: the biochemistry that actually makes this diagnosis — glucose, insulin, C-peptide, proinsulin, ketone bodies and routine bloods — ordered and reported by us; pancreatic-protocol CT and MRI; medical oncology, including systemic treatment for neuroendocrine tumours such as somatostatin-analogue-class therapy, mTOR-inhibitor-class treatment and TKI-class therapy where they are appropriate; genetic counselling where a MEN1 or other inherited pattern is suspected; nutrition and dietary planning around the episodes; and pain, psycho-oncology and supportive care, together with long-term follow-up afterwards.
Coordinated with specialist HPB, gastroenterology and endoscopy partner centres, and may be billed there: every operation on the pancreas, including shelling out an insulinoma and distal pancreatectomy; endoscopic ultrasound and the biopsy taken through it; ERCP and biliary or duodenal stenting; staging laparoscopy; coeliac plexus block; PET-CT and DOTATATE PET; and peptide receptor radionuclide therapy. We arrange these, we sit in on the decisions and we tell you in advance where each one happens and who invoices you. We do not describe them as our own theatre or endoscopy lists, because they are not.
If the biochemistry points somewhere else entirely and the diagnosis turns out to be the commoner ductal type of pancreatic cancer, pancreatic cancer treatment in Hyderabad sets out those options in full, and our complete pancreatic cancer guide covers the wider picture from symptoms through to survivorship.
The less common versions
When an Insulinoma Is Not a Single, Simple Tumour
Two situations change the plan, and both are worth knowing about rather than discovering late. The first is an inherited one. Where an insulinoma appears in a younger person, where there is more than one tumour, or where relatives have had tumours of the parathyroid or pituitary glands as well as the pancreas, an inherited condition called MEN1 comes into the conversation. That matters practically: it changes how the pancreas is searched, it raises the chance of further tumours over time, and it makes genetic counselling worth having for the family as well as for you. Genetic counselling is delivered in-house at CION.
The second is that a minority of insulinomas behave in a malignant way and spread, most often to the liver. This is much less common than the benign form, and it does not mean the situation is untreatable — neuroendocrine tumours generally grow more slowly and respond to a wider range of approaches than ductal pancreatic cancer does. Treatment then combines controlling the low blood sugars with controlling the tumour itself, using somatostatin-analogue-class therapy, mTOR-inhibitor-class or TKI-class treatment, liver-directed approaches, and in selected cases peptide receptor radionuclide therapy, which we coordinate with partner centres. Grade, measured by how fast the tumour cells are dividing, shapes which of these is chosen.
What does not change is the order of things. The biochemistry comes first, the tumour is located second, and the treatment decision is made by a team rather than by whoever looked at the scan. Bring every glucose reading you have, including the ones taken at home, and any account a family member can give of what an episode looks like from the outside.
If your episodes are being treated as anxiety and you are not convinced, that is a reasonable thing to bring to a specialist. Book a free consultation or call 1800 202 8726.
Take the next step
Most Insulinomas Are Benign and Curable
The hard part is being believed and getting the right test at the right moment. We start there.
Real Stories. Real Voices.
15,000+ patients chose CION. Hear from them directly.
These aren't paid endorsements or written reviews. These are video testimonials from real patients and families — recorded on their own phones, in their own words. Pick any one. Watch it. Then decide.
4.8★800+ Google reviews
50+video testimonials
15,000+patients treated
Read all 800+ reviews on Google
Start Your Story. Book Free Consultation.
Common questions
Insulinoma — your questions answered
Is an insulinoma cancer?
Not usually, and this is the most important thing to be clear about. The great majority of insulinomas are benign: they are small, they sit in one place in the pancreas, they do not spread, and removing the tumour normally ends the problem completely. What makes an insulinoma dangerous is not growth but the insulin it releases, which drops blood sugar and can cause confusion, seizures or loss of consciousness. A minority do behave in a malignant way and can spread, most often to the liver, and those are treated differently and over a longer period. Which situation you are in is established from the imaging, the operation findings and the pathology report, not from the symptoms alone, so it is worth waiting for those before drawing conclusions about it.
What are the first insulinoma symptoms most people notice?
Usually the adrenaline group: sweating, trembling, a racing heart, sudden anxiety, and hunger that feels urgent rather than ordinary. These come first because the body releases adrenaline to correct a falling glucose. If the glucose keeps falling, the brain symptoms follow - slow or muddled thinking, blurred vision, difficulty finding words, behaviour that family describe as not like you, and in a deep episode a seizure or a blackout. The pattern matters more than any single symptom. Episodes typically arrive when you have not eaten, first thing in the morning or after exercise, and settle within minutes of eating something sweet. Many people notice they have quietly rearranged their eating, snacking through the day or keeping food by the bed, to stop the episodes happening at all.
How is an insulinoma diagnosed?
Biochemically first, and by imaging only afterwards. The starting point is Whipple's triad: symptoms of low blood sugar, a genuinely low glucose measured while those symptoms are present, and relief once the glucose is raised. On the same blood sample, insulin, C-peptide, proinsulin and ketone bodies are measured, because insulin that is still switched on while glucose is falling is what makes the diagnosis. If no episode can be captured in daily life, a fast is carried out under close observation with regular sampling and stopped as soon as symptoms appear alongside a low glucose. A screen also excludes injected insulin and tablets that push the pancreas to release insulin. Only once the biochemistry is convincing is the tumour looked for, using pancreatic-protocol CT and MRI and often endoscopic ultrasound, since these tumours can be very small.
Can an insulinoma be cured?
For most people, yes. When the tumour is benign, single and can be removed completely, taking it out normally ends the low blood sugars for good and no further treatment is needed. That is the usual course of events, although nobody can promise an individual outcome before the tumour has been located and examined. The operation is either shelling the tumour out of the pancreas or removing a limited part of the gland, and it is coordinated with specialist HPB surgical partners rather than performed at CION. Where the tumour is malignant or has already spread, cure is less often the goal, but control frequently is: neuroendocrine tumours generally grow slowly and respond to several different systemic approaches, and the low blood sugars themselves can be managed alongside. Follow-up continues afterwards either way.
Why did it take so long for anyone to think of this?
Because the symptoms are episodic, they resolve with food, and every one of them is far more commonly caused by something else. Sweating, tremor and a sense of dread look like a panic attack. A seizure looks like epilepsy. Confusion and out-of-character behaviour in an older adult look like cognitive decline. Between episodes, examination and routine blood tests are usually completely normal, which is genuinely reassuring to whoever is looking. The one thing that cuts through is a glucose measured at the moment you feel unwell, together with the insulin markers from that same sample - and that sample is easy to miss, because by the time most people reach a clinic they have already eaten and feel fine. If you can get a reading during an episode, or a relative can describe one clearly, bring it.
Does an insulinoma run in families?
Most do not. The majority appear on their own with no family pattern behind them. A minority are part of an inherited condition called multiple endocrine neoplasia type 1, usually written MEN1, in which tumours can arise in the parathyroid and pituitary glands as well as the pancreas. This possibility is taken more seriously when the person is young, when more than one tumour is found in the pancreas, or when relatives have had hormone-producing tumours of any of those glands. It matters practically rather than theoretically: it changes how thoroughly the pancreas is searched, it means further tumours may appear over time, and it makes testing and counselling worth offering to relatives. Genetic counselling is provided in-house at CION, and we will tell you plainly whether your history warrants it.
What does CION do for a suspected insulinoma, and what happens at the first visit?
The first consultation is free and lasts 45 minutes. Bring every glucose reading you have, including ones taken at home, any blood results already done, and if possible someone who has watched an episode. We go through the pattern and work out whether the biochemistry has actually been done properly, because that is where most delayed diagnoses are lost. In-house across our 35+ centres we order and report the glucose, insulin, C-peptide, proinsulin and ketone body testing, arrange pancreatic-protocol CT and MRI, and provide medical oncology and systemic therapy for neuroendocrine tumours, genetic counselling, nutrition planning around the episodes, supportive care and long-term follow-up. Surgery to remove the tumour, endoscopic ultrasound and PET imaging are coordinated with specialist partner centres and may be billed there. We tell you in advance where each step happens and who invoices you.
Medical disclaimer: This page explains what an insulinoma is, how the diagnosis is made and how it is generally treated, and is reviewed by a CION medical oncologist with reference to NCCN guidance on neuroendocrine tumours and to endocrine society guidance on the evaluation of hypoglycaemia in adults. It is general information and not a diagnosis; low blood sugar has many causes and is very rarely due to a tumour, so your own symptoms should be assessed by your treating team. Diagnostic biochemistry and its reporting, pancreatic-protocol CT and MRI, medical oncology and systemic therapy for neuroendocrine tumours, genetic counselling, nutrition support, pain and psycho-oncology care and long-term follow-up are delivered by CION; all pancreatic surgery, endoscopic ultrasound and biopsy, ERCP and stenting, staging laparoscopy, coeliac plexus block, PET-CT and DOTATATE PET, and peptide receptor radionuclide therapy are coordinated with specialist HPB, gastroenterology and endoscopy partner centres and may be billed there.