Paraganglioma and Gastric Stromal Sarcoma Syndrome

Paraganglioma and gastric stromal sarcoma syndrome—better known medically as the Carney–Stratakis syndrome (CSS)—is a rare, inherited condition where a person can develop two kinds of tumors: (1) paragangliomas, which grow from nerve-related cells that can make stress hormones, and (2) gastric GIST, a stomach tumor that usually depends on cell-signaling proteins to grow. In CSS, both tumors are strongly linked to faults in the succinate dehydrogenase (SDH) genes (SDHA, SDHB, SDHC, SDHD), and these tumors often behave differently from “typical” GISTs: they are SDH-deficient (KIT/PDGFRA wild-type) and may not respond well to standard GIST drugs like imatinib. PMC+3Orpha.net+3NCBI+3

Paraganglioma and gastric stromal sarcoma syndrome is a rare inherited condition where a person can develop two kinds of tumors:

1. Paragangliomas (PGL), which are growths from neuroendocrine cells found from the skull base down to the pelvis; some secrete stress hormones (catecholamines) and some do not.

2. Gastrointestinal stromal tumors (GIST), which are tumors of the gut’s supporting (mesenchymal) tissue, most often in the stomach in this syndrome. PMC+1

This syndrome is also called the Carney–Stratakis syndrome (CSS) or Carney–Stratakis dyad. It is different from the Carney triad (which includes GIST, paraganglioma, and lung chondroma but usually isn’t due to inherited SDH mutations). CSS is typically caused by inherited (germline) changes in genes that form the succinate dehydrogenase (SDH) enzyme complex. PMC+1

The SDH enzyme is part of both the Krebs cycle and the mitochondrial respiratory chain (complex II). When a person inherits a faulty SDH gene (for example SDHB, SDHD, SDHC, or SDHA), their cells can lose SDH function. This leads to a buildup of succinate, which stabilizes HIF proteins and creates a “pseudo-hypoxia” signal. That abnormal signal can drive tumor formation in paraganglia and the stomach wall. These tumors are often SDH-deficient by pathology and behave differently from the more common KIT/PDGFRA-mutated GISTs. NCBI+2PNAS+2

SDH genes help cells use oxygen to make energy. When an SDH gene is faulty, the enzyme does not work properly. Waste products such as succinate build up and “trick” the cell into acting as if it lives in low oxygen, turning on growth signals (via HIF pathways) and helping tumors form. In CSS, this SDH problem links the risk of paraganglioma and gastric SDH-deficient GIST in the same person or family. ScienceDirect+1

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Other names

• Carney–Stratakis syndrome

• Carney–Stratakis dyad (PGL + GIST)

• Familial GIST–paraganglioma syndrome

• SDH-deficient GIST with paraganglioma (describing the biology) Orpha.net+1

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Types

By tumor type in this syndrome

• Paragangliomas (PGL)

  • Sympathetic PGLs (often in chest/abdomen/pelvis): more likely to secrete catecholamines and cause high blood pressure, palpitations, headache, and sweating.

  • Parasympathetic PGLs (often in the head and neck): usually non-secreting; symptoms relate to a neck mass, pressure, or nerve effects. NCBI

• Gastrointestinal stromal tumors (GIST)

  • In CSS they are usually stomach-based, often multifocal, and SDH-deficient on testing. They are commonly KIT/PDGFRA wild-type, which means standard GIST drugs may not work as well. PMC+2Gastrointestinal Stromal Tumor+2

By genetic type

• SDHB-related CSS, SDHD-related CSS, less commonly SDHC or SDHA. These follow autosomal dominant inheritance with variable penetrance; SDHD/SDHAF2 show a parent-of-origin effect (disease mainly when inherited from the father). NCBI+1

Causes

In this section “causes” means biological and genetic reasons that make this syndrome happen and factors that push tumors to appear or progress.

1. Germline SDHB variants – the most frequent SDHx genes in the dyad; associated with extra-adrenal PGLs and a higher metastatic risk. NCBI+1

2. Germline SDHC variants – classic in CSS with gastric SDH-deficient GIST. PMC

3. Germline SDHD variants – often linked with head/neck PGLs; penetrance affected by parent-of-origin effects. NCBI

4. Less common SDHA variants – also disrupt the SDH complex and can cause SDH-deficient tumors. NCBI

5. SDH assembly factor defects (e.g., SDHAF2) – rare but impair SDH function. NCBI

6. Second-hit inactivation in tumor tissue (loss of the remaining normal allele) – turns a predisposition into an actual tumor. NCBI

7. Accumulation of succinate – the broken SDH step lets succinate build up and act as an “on” signal for growth. PNAS

8. Pseudohypoxia/HIF pathway activation – cells behave like they are starved of oxygen, driving tumor pathways. PNAS

9. Inhibition of 2-oxoglutarate–dependent enzymes (e.g., prolyl hydroxylases) – another route to HIF stabilization. PNAS

10. Epigenetic changes (promoter hypermethylation) in SDH-related genes – seen particularly in SDH-deficient tumor biology. Bioscientifica

11. Mitochondrial metabolic stress – energy-chain disturbance promotes reactive oxygen species and signaling. PNAS

12. Angiogenesis up-regulation (e.g., VEGF) – tumor blood-vessel growth encouraged by hypoxia signaling. PNAS

13. Developmental origin of paraganglia – distributed along the paravertebral axis, offering many potential tumor sites. NCBI

14. Gastric ICC niche susceptibility – SDH loss particularly affects stomach GIST development. PMC

15. Parent-of-origin (imprinting) effects in SDHD – paternal transmission confers higher risk than maternal in many families. NCBI

16. Incomplete penetrance – not everyone with a variant gets tumors, but risk remains lifelong; surveillance matters. NCBI

17. Younger age at onset (often childhood–young adult) – reflects inherited predisposition. Frontiers

18. Multifocality – more than one paraganglioma or multiple gastric GISTs may appear over time. PubMed

19. Association with “quadruple wild-type” biology in GIST – subset that lacks common driver mutations and is SDH-intact or altered differently, underscoring pathway diversity. Wiley Online Library

20. Distinct from Carney triad’s non-germline mechanism – helps explain why some patients have dyad (heritable) vs triad (usually non-heritable). PMC+1

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Symptoms

Symptoms vary with where the tumor is and whether a paraganglioma makes hormones. People may have one, several, or none for a long time.

1. Headache “spells” – sudden pounding headaches from catecholamine surges. NCBI

2. Palpitations – fast or pounding heartbeats during attacks. NCBI

3. Sweating and flushing – classic with functional sympathetic PGLs. NCBI

4. High blood pressure (sustained or paroxysmal) – can be severe or intermittent. NCBI

5. Anxiety or panic-like episodes – adrenaline-like symptoms without emotional triggers. NCBI

6. Neck or skull-base mass – painless lump, hoarseness, difficulty swallowing, or ear “whooshing” for head/neck PGL. NCBI

7. Abdominal or chest discomfort – from deep PGLs pressing on surrounding tissues. 

8. Belly pain or fullness after small meals – gastric GIST related early satiety. 

9. Nausea or vomiting – from gastric outlet irritation. 

10. Black or bloody stools – GISTs can ulcerate and bleed into the stomach. 

11. Iron-deficiency anemia – tiredness, pale skin from chronic occult bleeding. 

12. Weight loss – from tumor metabolism, poor appetite, or fear of eating due to pain. 

13. Dizziness or fainting – especially during catecholamine spikes. NCBI

14. Tinnitus or hearing changes – with carotid-body or jugulotympanic PGLs. NCBI

15. No symptoms – some tumors are found incidentally during imaging or family screening. NCBI

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Diagnostic tests

The aim of testing is to: (1) confirm a tumor is present; (2) characterize its type and behavior; (3) measure hormones if secretory; (4) define genetics for the person and family; and (5) plan surveillance.

A) Physical examination

1. Vital signs with repeated blood pressures (including during or after “spells”) – documents hypertension or paroxysmal rises typical of catecholamine release. NCBI

2. Orthostatic vitals – checks for drops or surges when standing; can hint at autonomic effects of catecholamines. NCBI

3. Head and neck inspection/palpation – may reveal a pulsatile mass at the carotid bifurcation or skull base tenderness suggesting head/neck PGL. NCBI

4. Abdominal exam – assesses tenderness, masses, or fullness that might suggest deep PGL or gastric tumor. 

5. General exam for anemia signs (pallor, fast heart rate) – supports chronic GIST bleeding. 

B) “Manual” bedside tests

6. Manual (cuff) repeated BP monitoring across a day – captures variability/spikes; helpful when spells are intermittent. NCBI

7. Focused cranial-nerve exam – bedside checks for hoarseness, tongue deviation, or swallowing issues caused by head/neck PGL mass effect. NCBI

8. Stool guaiac cards (FOBT) – simple bedside test to detect hidden blood from a bleeding gastric GIST. 

C) Laboratory & pathological tests

9. Plasma free metanephrines (or urine fractionated metanephrines) – first-line biochemical test for secretory PGL; very sensitive. NCBI

10. Catecholamines (plasma/urine) – supportive testing if metanephrines are equivocal or to quantify hormone output. NCBI

11. Complete blood count (CBC) – looks for iron-deficiency anemia from GIST bleeding (low Hb, low MCV). 

12. Ferritin, iron studies – confirm iron loss pattern. 

13. Endoscopic biopsy of gastric mass – provides tissue for diagnosis when safe; small bites to limit bleeding risk. Pathology plus IHC confirm GIST. 

14. Immunohistochemistry (IHC) panel – DOG1 and KIT often positive; SDHB negative (loss of staining) indicates SDH deficiency; helps separate CSS-type GIST from typical KIT/PDGFRA-mutant GIST. PMC+1

15. Molecular testing of tumor – often wild-type for KIT/PDGFRA; SDHx changes or epigenetic alterations define biology and influence therapy. Translational Cancer Research

D) Electrodiagnostic tests

16. 12-lead ECG – evaluates tachyarrhythmias or ischemic strain from catecholamine surges; also baseline before any alpha-/beta-blockade or surgery. NCBI

17. Ambulatory (Holter) ECG or 24-h BP monitoring – documents paroxysmal spikes or rhythm changes during spells. NCBI

E) Imaging tests

18. MRI (or CT) from skull base to pelvis – imaging survey to locate all PGL sites and characterize gastric lesions; MRI is preferred in many centers to limit radiation, especially in younger patients. Nature

19. ^68Ga-DOTATATE PET/CT (somatostatin-receptor PET) – highly sensitive functional imaging for PGLs and often helpful in SDH-deficient tumors. Nature

20. Upper endoscopy ± CT enterography – visualizes the gastric mass directly, assesses ulceration/bleeding, and guides biopsy and surgical planning. 

Why genetics matter in testing: Because CSS is inherited, germline testing of SDHx genes is recommended once a PGL or SDH-deficient GIST is confirmed. Results guide family screening and age-appropriate surveillance. NCBI+1

Non-pharmacological management

1. Genetic counseling & SDHx testing. Purpose: confirm the inherited cause and guide screening for you and relatives. Mechanism: a DNA test finds the SDH gene change; results determine lifelong surveillance plans. NCBI

2. Pre-operative education and “calm-surgery” plan. Purpose: lower risk during tumor removal. Mechanism: teaching salt/fluid loading, medication timing, and anesthesia plans reduces blood-pressure swings. OUP Academic

3. High-salt diet + hydration (before PPGL surgery). Purpose: prevent dangerous low blood pressure after blocking alpha receptors. Mechanism: more salt and water expand blood volume. OUP Academic

4. Avoid triggers for catecholamine surges. Purpose: prevent attacks. Mechanism: limit severe stress, certain drugs (e.g., decongestants), and sudden posture changes that spike BP. OUP Academic

5. Anesthetic team with PPGL experience. Purpose: safer surgery. Mechanism: experts anticipate BP spikes and manage with IV drugs and monitoring. OUP Academic

6. Surgical resection of paraganglioma when feasible. Purpose: cure or debulk hormone source. Mechanism: removing the tumor stops excess catecholamines and mass effects. Cancer.gov

7. Organ-preserving adrenal surgery if needed. Purpose: keep adrenal function when possible. Mechanism: partial adrenalectomy balances tumor control with hormone needs. OUP Academic

8. Oncologic surgery for gastric SDH-deficient GIST. Purpose: local control and bleeding prevention. Mechanism: wedge/limited gastrectomy with gentle handling to avoid rupture. NCCN

9. Multidisciplinary tumor board care. Purpose: align endocrine, surgery, oncology, pathology, genetics, and nuclear medicine. Mechanism: team decisions improve sequencing of tests and treatments. OUP Academic

10. Imaging-guided surveillance schedule. Purpose: catch new tumors early. Mechanism: periodic MRI/CT and functional scans detect recurrences or new lesions. OUP Academic

11. Iron repletion and anemia support. Purpose: restore energy if GIST bleeds. Mechanism: oral/IV iron and diet counseling correct iron-deficiency anemia. Espen

12. Nutrition counseling (ESPEN/ASCO aligned). Purpose: maintain strength and tolerate therapy. Mechanism: screen for malnutrition; aim ~25–30 kcal/kg/day and 1–1.5 g/kg/day protein; prefer whole-food, plant-forward patterns. Espen+2Espen+2

13. Physical activity as tolerated. Purpose: reduce fatigue, maintain fitness, and quality of life. Mechanism: moderate, individualized exercise is safe for most patients during treatment. ASC Publications

14. Psychological support. Purpose: reduce anxiety from “adrenaline attacks” and surveillance stress. Mechanism: counseling and coping strategies lower sympathetic arousal. Cancer.gov

15. Fertility and pregnancy planning. Purpose: plan safe timing around surgery or radionuclide therapy. Mechanism: preconception counseling and therapy scheduling reduce fetal risk. OUP Academic

16. Nuclear medicine triage. Purpose: decide between somatostatin-targeted therapy or MIBG. Mechanism: DOTATATE PET predicts somatostatin-based options; MIBG scan predicts I-131-MIBG candidacy. PMC+1

17. Blood pressure self-monitoring. Purpose: track control on alpha-/beta-blockers. Mechanism: home logs help clinicians titrate safely. OUP Academic

18. Smoking cessation. Purpose: reduce vascular and surgical risks. Mechanism: lowers complications and improves wound healing. Espen

19. Vaccination up-to-date. Purpose: avoid preventable infections during systemic therapy or after major surgery. Mechanism: routine immunizations per adult schedules. Espen

20. Family cascade screening. Purpose: protect relatives. Mechanism: identify SDHx carriers early and start surveillance even if asymptomatic. NCBI

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Drug treatments

1. Belzutifan (WELIREG) — on-label (PPGL)
   Class: HIF-2α inhibitor. Dose: commonly 120 mg once daily (per label). Purpose: first oral FDA-approved therapy for unresectable/metastatic pheochromocytoma/paraganglioma (May 14, 2025). Mechanism: blocks HIF-2α signaling that is overactive in SDHx-related tumors. Side effects: anemia, fatigue, hypoxia risk; contraception needed. U.S. Food and Drug Administration+2FDA Access Data+2

2. Iobenguane I-131 (AZEDRA) — on-label (PPGL)
   Class: targeted radiotherapy. Dosing: weight/uptake-based dosimetry, IV. Purpose: treats iobenguane-scan-positive, unresectable or metastatic PPGL (≥12 years). Mechanism: norepinephrine analog carries radioactive iodine to tumor cells. Key risks: myelosuppression, hypothyroidism, radiation precautions. FDA Access Data+1

3. Phenoxybenzamine (Dibenzyline) — on-label (PPGL pre-op)
   Class: non-selective irreversible α-blocker. Dose: titrated orally. Purpose: first-line to control BP and prevent intra-op crises before PPGL surgery. Mechanism: blocks α-receptors to blunt vasoconstriction from catecholamines. Side effects: orthostatic hypotension, nasal stuffiness, fatigue. FDA Access Data+1

4. Metyrosine (Demser) — on-label adjunct (PPGL)
   Class: tyrosine hydroxylase inhibitor. Dose: divided oral doses. Purpose: reduces catecholamine synthesis when α-blockade is insufficient. Side effects: sedation, diarrhea, anxiety, crystalluria—hydrate well. DailyMed

5. Octreotide (Sandostatin/LAR) — on-label for GEP-NET symptoms; off-label in PPGL with SSTR
   Class: somatostatin analog. Dose: short-acting SC t.i.d., then LAR monthly. Purpose: control hormone-related symptoms and as imaging-driven therapy in SSTR-positive disease. Risks: gallstones, glucose changes. FDA Access Data+1

6. Lanreotide (Somatuline Depot) — on-label for GEP-NET; off-label in SSTR-positive PPGL
   Class: somatostatin analog, deep SC q4w. Purpose: symptom control and disease stabilization in SSTR-positive tumors. Risks: similar to octreotide. FDA Access Data+1

7. Imatinib (Gleevec) — on-label (KIT+ or PDGFRA+ GIST); limited in SDH-deficient GIST
   Class: TKI against KIT/PDGFRA. Dose: 400 mg daily typical. Purpose: standard for KIT-mutant GIST; however, SDH-deficient gastric GISTs are usually wild-type and respond poorly. Side effects: edema, fatigue, cytopenias. FDA Access Data+2FDA Access Data+2

8. Sunitinib (Sutent) — on-label (imatinib-resistant GIST); activity in SDH-deficient GIST
   Class: multi-TKI (VEGFR, KIT). Dose: 50 mg daily, 4/2 schedule. Purpose: second-line for GIST; small studies suggest activity in SDH-deficient GIST. Risks: hypertension, hand-foot syndrome. FDA Access Data+1

9. Regorafenib (Stivarga) — on-label (post-imatinib/sunitinib GIST)
   Class: multi-TKI. Dose: 160 mg daily 21/7. Purpose: third-line GIST; small series show activity in SDH-deficient disease. Risks: HFSR, HTN, fatigue, LFT elevation. FDA Access Data+1

10. Ripretinib (Qinlock) — on-label (≥4th-line GIST)
    Class: switch-control TKI. Dose: 150 mg daily. Purpose: later-line control for advanced GIST of many genotypes; role in SDH-deficient is limited but may stabilize. Risks: alopecia, myalgia, HFSR. FDA Access Data

11. Avapritinib (Ayvakit) — on-label (PDGFRA exon 18–mutant GIST)
    Class: PDGFRA-selective TKI. Dose: 300 mg daily. Purpose: highly effective for PDGFRA D842V GIST; not useful for SDH-deficient tumors unless that mutation exists. Risks: edema, cognitive effects. FDA Access Data

12. Short-acting β-blockers (e.g., propranolol, esmolol) — adjunct, off-label in PPGL
    Class: β-blockers. Purpose: only after α-blockade to control tachycardia. Mechanism: blunts heart rate, avoids unopposed α-stimulation. Risks: bradycardia, bronchospasm. OUP Academic

13. Calcium-channel blockers (e.g., nicardipine) — adjunct, off-label in PPGL
    Purpose: additional BP control when α-blockers not tolerated or insufficient. Mechanism: vasodilation without interfering with catecholamine synthesis. OUP Academic

14. Temozolomide — on-label (gliomas); off-label for SDHB-mutant metastatic PPGL
    Class: alkylator. Purpose: responses reported especially in SDHB-mutant PPGL; used when radionuclide or targeted therapy not suitable. Label risks: myelosuppression, nausea. Cancer.gov

15. Pazopanib — on-label (soft-tissue sarcoma); off-label in SDH-deficient GIST
    Class: VEGFR-targeting TKI. Purpose: small studies suggest disease control in SDH-deficient GIST. Risks: hypertension, hepatotoxicity. PMC

16. Cabozantinib — on-label (RCC, DTC, HCC); off-label in PPGL
    Class: multi-TKI. Purpose: used in metastatic PPGL in reports/trials; not FDA-approved for PPGL. Risks: diarrhea, HFSR, HTN. Cancer.gov

17. Everolimus — on-label (NETs, RCC); off-label in PPGL
    Class: mTOR inhibitor. Purpose: occasional use for disease stabilization; evidence limited. Risks: mucositis, hyperglycemia. Cancer.gov

18. Labetalol — on-label (hypertension); adjunct after α-blockade in PPGL
    Class: combined α/β-blocker. Purpose: useful when tachycardia persists after α-blockade. Risks: hypotension, fatigue. OUP Academic

19. Doxazosin — on-label (hypertension/BPH); off-label α1-blocker for PPGL
    Purpose: alternative to phenoxybenzamine for pre-op blockade; may have fewer side effects but is reversible. Risks: orthostasis. OUP Academic

20. Somatostatin-receptor radionuclide therapy (177Lu-DOTATATE) — on-label for SSTR-positive GEP-NETs; off-label in PPGL
    Class: radioligand therapy. Purpose: for SSTR-positive PPGL when suitable; strong biologic rationale and case-series benefit. Risks: cytopenias, renal monitoring. PMC

Important clarity: Items 12–20 include commonly used adjuncts or off-label options in PPGL/SDH-deficient GIST; I anchored each to authoritative guidelines or FDA labels for transparency. Where the label is for another cancer, I’ve said so plainly. OUP Academic+1

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Dietary molecular supplements

There are no supplements that shrink PPGL or SDH-deficient GIST, but good nutrition protects strength and helps you tolerate treatment. Always discuss supplements with your clinician to avoid drug interactions.

1. Iron (when iron-deficient). Dose: per labs (often 65 mg elemental iron 1–2×/day or IV). Function/mechanism: rebuilds hemoglobin after slow gastric bleeding. Espen

2. Vitamin B12 & Folate (if deficient). Dose: per labs. Mechanism: supports red-blood-cell production and nerve health; check before replacing. Espen

3. Vitamin D. Dose: per level. Mechanism: bone and muscle support during reduced activity. Espen

4. Protein supplements (whey/pea). Dose: to reach ~1–1.5 g/kg/day total. Mechanism: maintains lean mass during therapy. Espen

5. Omega-3 (fish oil). Dose: individualized. Mechanism: may help maintain weight/appetite in some cancer patients; monitor bleeding risk. Espen

6. Oral nutrition formulas. Dose: as needed. Mechanism: convenient calories/protein when intake is low. Espen

7. Electrolyte solutions (during vomiting/diarrhea). Dose: as directed. Mechanism: prevent dehydration and hypotension on α-blockade. Espen

8. Multivitamin (standard dose). Mechanism: fills minor gaps without mega-doses (ASCO/ACS do not endorse special “cancer cures”). ScienceDirect+1

9. Fiber (food first, or psyllium). Mechanism: supports bowel regularity, which can be disturbed by TKIs/opioids. American Cancer Society

10. Caffeine moderation plan. Mechanism: avoids compounding tachycardia in PPGL patients; simple lifestyle step. OUP Academic

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Immune-booster / regenerative / stem-cell drugs

There are no approved immune-booster, regenerative, or stem-cell “drugs” proven to treat paraganglioma or SDH-deficient GIST. Using such products outside clinical trials can be risky or fraudulent. Safer, evidence-based options include the approved/established treatments above and enrollment in clinical trials when appropriate. Cancer.gov

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Surgery

1. Excision of head/neck paraganglioma (open or endoscopic skull-base techniques). Why: relieve mass effect/nerve compression in non-secretory tumors. Control bleeding and preserve nerves when possible. Cancer.gov

2. Adrenal or extra-adrenal PPGL resection with full pre-op α-blockade. Why: curative intent for functional tumors; prevents crises. OUP Academic

3. Partial adrenalectomy in select patients. Why: preserve adrenal function in hereditary disease with bilateral risk. OUP Academic

4. Gastric wedge resection/limited gastrectomy for SDH-deficient GIST. Why: control bleeding, prevent rupture/spread; lymph node dissection is uncommon. NCCN

5. Re-resection of local recurrence or metastasectomy (selected cases). Why: symptom control (bleeding/pain) and occasional durable control when disease is limited. NCCN

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Prevention & early-action tips

Because this is hereditary risk, prevention means early detection and reducing complications:

1. Genetic counseling + SDHx testing for you/relatives. NCBI

2. Lifelong imaging/biochemical surveillance per risk and age. OUP Academic

3. Pre-op α-blockade for any functional PPGL before surgery. OUP Academic

4. Avoid decongestants/stimulants that spike BP (e.g., pseudoephedrine). OUP Academic

5. Keep hydration and salt per medical advice during blockade. OUP Academic

6. Report GI bleeding signs early (black stools, fatigue). NCCN

7. Stop smoking; limit alcohol. Espen

8. Maintain activity and nutrition to protect strength. ASC Publications+1

9. Carry a medical alert card (PPGL history; α-blocker use). OUP Academic

10. Use experienced centers for surgery and nuclear therapies. OUP Academic

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When to see a doctor

Seek care immediately for severe headache, chest pain, shortness of breath, or a hypertensive crisis. Arrange urgent assessment if you have new spells of palpitations/sweating, unexplained high BP, black stools, sudden fatigue, or a new neck/abdominal mass. People with SDHx variants should be followed in a clinic familiar with hereditary PPGL/GIST. Cancer.gov+1

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What to eat and what to avoid

1. Eat: varied vegetables, fruits, whole grains, legumes—most of your plate. Why: supports weight, gut health, and long-term wellness. Avoid: ultra-processed snacks. American Cancer Society

2. Eat: lean proteins (fish, poultry, soy, dairy or alternatives). Avoid: frequent red/processed meats. American Cancer Society

3. Eat: enough calories and 1–1.5 g/kg/day protein if losing weight. Avoid: crash diets during treatment. Espen

4. Use: iron-rich foods (meat/legumes/greens) if anemic. Avoid: tea/coffee with iron pills (reduces absorption). Espen

5. Hydrate well, especially on α-blockers. Avoid: dehydration and excessive alcohol. OUP Academic

6. Prefer: small, frequent meals if nausea. Avoid: greasy, spicy foods during flares. Espen

7. Limit caffeine if PPGL is active (may worsen palpitations). OUP Academic

8. Consider dietitian referral for personalized plans. Espen

9. Keep fiber for bowel regularity; adjust around scans or surgery. American Cancer Society

10. Be cautious with supplements claiming to “boost immunity” or “shrink tumors.” ScienceDirect

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FAQs

1. Is CSS the same as Carney triad?
   No. Carney triad involves GIST, paraganglioma, and lung chondroma (often non-inherited). Carney–Stratakis is the hereditary dyad (GIST + paraganglioma) linked to SDHx. Orpha.net

2. Do all patients get both tumors?
   No. Risk is increased for each, but penetrance is incomplete; some develop only one. Lifelong surveillance is advised. NCBI

3. Which test best screens for functional PPGL?
   Plasma free metanephrines are most sensitive; 24-h urine metanephrines help confirm. OUP Academic

4. What imaging is best for SDHx tumors?
   [^68Ga]-DOTATATE PET/CT is highly sensitive; FDG PET helps in aggressive disease; MIBG is used to pick candidates for I-131 MIBG therapy. PMC

5. Can imatinib cure SDH-deficient GIST?
   Most SDH-deficient GISTs lack KIT/PDGFRA mutations, so benefit from imatinib is limited; sunitinib or regorafenib may help more. PMC

6. What’s new for metastatic PPGL?
   Belzutifan (2025) is the first oral FDA-approved systemic therapy for advanced PPGL; AZEDRA is the radiotherapeutic option for MIBG-avid disease. U.S. Food and Drug Administration+1

7. Why is pre-op α-blockade critical?
   It prevents life-threatening BP spikes during anesthesia and tumor handling. Salt and fluids reduce post-op hypotension. OUP Academic

8. Are somatostatin analogs useful?
   If tumors express somatostatin receptors, octreotide/lanreotide can control symptoms and sometimes slow growth. FDA Access Data+1

9. What about PRRT (177Lu-DOTATATE)?
   It’s approved for SSTR-positive GEP-NETs and used off-label in SSTR-positive PPGL after multidisciplinary review. PMC

10. How often should I be checked if I’m SDHx-positive?
    Lifelong, risk-based schedules typically include periodic metanephrines and imaging (MRI/functional scans). OUP Academic

11. Do I need a high-salt diet forever?
    No. It’s used short-term pre-op with α-blockade for PPGL surgery; afterwards your team individualizes diet. OUP Academic

12. Can children be affected?
    Yes—CSS is hereditary; testing and age-appropriate surveillance are considered in families. NCBI

13. Are there lifestyle cures?
    No. Healthy food and activity support strength but do not shrink these tumors. Use proven medical/surgical care. American Cancer Society

14. Is MIBG therapy still available?
    Yes. AZEDRA remains an FDA-approved option for MIBG-avid unresectable/metastatic PPGL. FDA Access Data

15. Where should I be treated?
    Centers with endocrine oncology, advanced imaging, genetics, and nuclear therapy programs offer the safest, most coordinated care. OUP Academic

Disclaimer: Each person’s journey is unique, treatment plan, life style, food habit, hormonal condition, immune system, chronic disease condition, geological location, weather and previous medical  history is also unique. So always seek the best advice from a qualified medical professional or health care provider before trying any treatments to ensure to find out the best plan for you. This guide is for general information and educational purposes only. Regular check-ups and awareness can help to manage and prevent complications associated with these diseases conditions. If you or someone are suffering from this disease condition bookmark this website or share with someone who might find it useful! Boost your knowledge and stay ahead in your health journey. We always try to ensure that the content is regularly updated to reflect the latest medical research and treatment options. Thank you for giving your valuable time to read the article.

The article is written by Team RxHarun and reviewed by the Rx Editorial Board Members

Last Updated: November 11, 2025.

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