Skip to content
How It Works
Explore
Ask a Question Resources Pricing
Who It's For
Patients
Decode results, prep for appointments, weigh options.
Caregivers & advocates
Carry the research load for someone you love.
Providers & clinicians
Resources for patients in your practice.
Log In Sign Up
PubMed This is a summary of 19 peer-reviewed journal articles Updated
Vascular Medicine · Segmental Progressive Overgrowth Syndrome

Symptoms & Warning Signs: What to Look For

At a Glance

Segmental progressive overgrowth often develops gradually, but sudden limb swelling, new severe pain, blue or pale discoloration, or shortness of breath and chest pain may signal a vascular emergency and require same-day or emergency medical care.

Monitoring Segmental Progressive Overgrowth means becoming an expert in the “baseline”—what the body normally looks and feels like—so you can quickly spot any changes. While most of the growth you will see is slow and expected, the condition can involve vascular malformations (abnormal collections of blood or lymph vessels) that require close attention to specific warning signs [1][2].

Physical Symptoms of Overgrowth

The most visible sign of this condition is asymmetric overgrowth, where one part of the body grows larger or faster than the other [3]. In fibroadipose hyperplasia, this is primarily an overgrowth of fat and tough fibrous tissue [4].

  • Limb and Digit Changes: You may notice one leg or arm becoming thicker or longer than the other, or individual fingers or toes (macrodactyly) becoming significantly enlarged [5].
  • Gait and Mobility: As limbs grow at different rates, it can create a limb-length discrepancy. This often leads to changes in how you walk (gait disturbances) and can eventually cause the spine to curve (scoliosis) as the body tries to compensate [5][6].
  • Chronic Pain: Overgrowth can be heavy and uncomfortable. You may experience persistent aching or a feeling of “heaviness” in the affected area, especially after a day of activity [7][8].
  • Vascular Signs: You may see “port-wine” stains (flat, reddish-purple birthmarks), prominent veins just under the skin, or areas that feel slightly warmer than the rest of the body [1][9]. Note that visible veins are nonspecific and cannot be used at home to classify a lesion as slow-flow or fast-flow.

When to Seek Immediate Help

Some vascular malformation syndromes in PROS carry a risk of blood clots, known as venous thromboembolism [2]. This individualized risk is highly variable, but is highest after surgery, during periods of immobility (like being in a cast), or if there are complex venous malformations or localized intravascular coagulopathy [10][11]. Do not start aspirin or anticoagulants without a clinician’s specific plan.

EMERGENCY: Call 911 or Go to the ER

These signs may indicate a Pulmonary Embolism (PE), where a blood clot has traveled to the lungs. This is a life-threatening emergency [12].

  • Sudden shortness of breath or difficulty breathing [13].
  • Sharp chest pain that may feel worse when taking a deep breath [12].
  • Fainting or sudden collapse [14].
  • Coughing up blood.
  • Rapid heartbeat or a look of extreme distress.

URGENT VASCULAR/LIMB EMERGENCY

These signs may indicate acute limb ischemia, severe venous obstruction, or another limb emergency. Go to the ER immediately [15].

  • Severe blue or pale discoloration of a limb accompanied by intense pain, numbness, or inability to use the limb.

URGENT: Call Your Doctor for a Same-Day Evaluation

These signs may indicate a Deep Vein Thrombosis (DVT), localized infection, or bleeding. Emergency services or a pediatric emergency department may be appropriate [16].

  • Sudden swelling in one limb that is rapidly enlarging or significantly worse than the usual overgrowth [17].
  • Marked warmth and redness in a specific area of the affected limb.
  • New tenderness, severe pain, or an ill-appearing patient.
  • New fever or sudden neurologic changes.

Routine vs. Urgent Changes

It is natural to feel anxious about every change, but understanding your baseline helps distinguish routine symptoms from urgent ones.

  • Slow, steady growth: The “progressive” nature of this condition means you may see gradual increases in size over months and years. This should be discussed at regular specialist appointments [18].
  • Typical pain flares: Unchanged mild symptoms or familiar discomfort after physical activity can often be managed chronically. However, new or substantially different pain is never just “growing pains” and needs evaluation; relief with an over-the-counter medicine does not exclude thrombosis, localized coagulopathy, infection, or bleeding [19].
  • Stable skin markings: Birthmarks or visible veins that have not changed in size, color, or texture are generally not a cause for immediate concern [1]. However, new bleeding or rapidly enlarging swelling requires advice.

By tracking the baseline, you can ensure you receive rapid care for true emergencies while maintaining a sense of calm during the day-to-day management of the overgrowth.

Common questions in this guide

What symptoms can segmental progressive overgrowth cause?
The main features are uneven growth of a limb or individual fingers or toes, sometimes with a difference in limb length. This can lead to gait changes, back curvature, pain, or a heavy feeling in the affected area. Port-wine stains, prominent veins, or warmer skin may also occur when vascular malformations are present.
What are emergency signs of a pulmonary embolism in PROS?
Call 911 or go to an emergency department for sudden trouble breathing, sharp chest pain that worsens with a deep breath, fainting, coughing up blood, or a very rapid heartbeat. These symptoms can occur when a blood clot travels to the lungs and may be life-threatening.
When should sudden swelling or pain in an overgrown limb be checked?
Sudden swelling, marked warmth or redness, new tenderness or severe pain, fever, an ill appearance, or sudden neurologic changes need same-day medical evaluation. A limb that becomes severely blue or pale with intense pain, numbness, or inability to use it requires immediate emergency care.
How can I tell normal progression from a warning sign?
Slow changes in size over months or years and stable birthmarks or visible veins may match the usual baseline. Rapid swelling, new or substantially different pain, new bleeding, or a sudden change in function is not typical and should be assessed by a clinician.
When is the risk of blood clots higher with PROS?
The risk varies from person to person and can be higher after surgery, during prolonged immobility such as wearing a cast, or when complex venous malformations or a localized clotting problem called localized intravascular coagulopathy are present. Ask the treating team for an individualized prevention plan, and do not start aspirin or an anticoagulant without specific medical instructions.
Can visible veins or skin birthmarks show whether a vascular lesion is slow-flow or fast-flow?
No. Visible veins are nonspecific, and changes seen at home cannot reliably classify a vascular lesion as slow-flow or fast-flow. Your clinician uses the examination and imaging to assess the lesion; new bleeding or rapidly increasing swelling should prompt medical advice.

Get notified when new evidence is published on Segmental progressive overgrowth syndrome with fibroadipose hyperplasia.

We monitor PubMed for new peer-reviewed studies on this topic and email a short summary when something meaningful changes.

References

References (19)
  1. 1

    Wound-Healing Problems Associated with Combined Vascular Malformations in Klippel-Trenaunay Syndrome.

    Ishikawa K, Yamamoto Y, Funayama E, et al.

    Advances in wound care 2019; (8(6)):246-255 doi:10.1089/wound.2018.0835.

    PMID: 31832274
  2. 2

    PIK3CA vascular overgrowth syndromes: an update.

    Hughes M, Hao M, Luu M

    Current opinion in pediatrics 2020; (32(4)):539-546 doi:10.1097/MOP.0000000000000923.

    PMID: 32692051
  3. 3

    PIK3CA Mutational Analysis in Patients With Macrodactyly.

    Becker J, Gross UC, Weber DM, et al.

    Pediatric and developmental pathology : the official journal of the Society for Pediatric Pathology and the Paediatric Pathology Society 2022; (25(6)):624-634 doi:10.1177/10935266221080155.

    PMID: 36314082
  4. 4

    A Review on Cutaneous and Musculoskeletal Manifestations of CLOVES Syndrome.

    Öztürk Durmaz E, Demircioğlu D, Yalınay Dikmen P, et al.

    Clinical, cosmetic and investigational dermatology 2022; (15()):621-630 doi:10.2147/CCID.S351637.

    PMID: 35444443
  5. 5

    Evolution over Time of Leg Length Discrepancy in Patients with Syndromic and Isolated Lateralized Overgrowth.

    Carli D, De Pellegrin M, Franceschi L, et al.

    The Journal of pediatrics 2021; (234()):123-127 doi:10.1016/j.jpeds.2021.01.020.

    PMID: 33465347
  6. 6

    Work-Up and Treatment Strategies for Individuals with PIK3CA-Related Disorders: A Consensus of Experts from the Scientific Committee of the Italian Macrodactyly and PROS Association.

    Gazzin A, Leoni C, Viscogliosi G, et al.

    Genes 2023; (14(12)) doi:10.3390/genes14122134.

    PMID: 38136956
  7. 7

    Gait disturbance and lower limb pain in a patient with PIK3CA-related disorder.

    Cappuccio G, Alagia M, D'Anna M, et al.

    European journal of medical genetics 2017; (60(12)):655-657 doi:10.1016/j.ejmg.2017.08.018.

    PMID: 28867506
  8. 8

    Qualitative research with patients and caregivers of patients with PIK3CA related overgrowth spectrum: content validity of clinical outcome assessments.

    Raymond K, Vallow S, Saucier C, et al.

    Journal of patient-reported outcomes 2022; (6(1)):75 doi:10.1186/s41687-022-00481-8.

    PMID: 35829859
  9. 9

    Complex vascular anomalies and tissue overgrowth of limbs associated with increased skin temperature and peripheral venous dilatation: parks weber syndrome or PROS?

    Su LX, Sun Y, Wang Z, et al.

    Hereditas 2022; (159(1)):1 doi:10.1186/s41065-021-00217-6.

    PMID: 34980271
  10. 10

    Characterization of thrombosis in patients with Proteus syndrome.

    Keppler-Noreuil KM, Lozier JN, Sapp JC, Biesecker LG

    American journal of medical genetics. Part A 2017; (173(9)):2359-2365 doi:10.1002/ajmg.a.38311.

    PMID: 28627093
  11. 11

    Thrombosis risk factors in PIK3CA-related overgrowth spectrum and Proteus syndrome.

    Keppler-Noreuil KM, Lozier J, Oden N, et al.

    American journal of medical genetics. Part C, Seminars in medical genetics 2019; (181(4)):571-581 doi:10.1002/ajmg.c.31735.

    PMID: 31490637
  12. 12

    Development and validation of a prediction model to estimate risk of acute pulmonary embolism in deep vein thrombosis patients.

    Li Y, He Y, Meng Y, et al.

    Scientific reports 2022; (12(1)):649 doi:10.1038/s41598-021-04657-y.

    PMID: 35027609
  13. 13

    Pulmonary embolism after shoulder surgery: Is it a real threat?

    Pitsilos C, Papadopoulos P, Givissis P, Chalidis B

    World journal of methodology 2025; (15(1)):98343 doi:10.5662/wjm.v15.i1.98343.

    PMID: 40115404
  14. 14

    Venous Thromboembolism for the Practicing Cardiologist.

    Pribish AM, Secemsky EA, Schmaier AA

    Cardiology clinics 2021; (39(4)):551-566 doi:10.1016/j.ccl.2021.06.008.

    PMID: 34686267
  15. 15

    Right Lower Extremity Phlegmasia Cerulea Dolens Due to Iliotibial Vein Thrombosis With Compartment Syndrome and Circulatory Shock: Case Report and Review.

    Dah K, Ogbu IR, Ngwudike C, Tripathi M

    Cureus 2022; (14(12)):e32364 doi:10.7759/cureus.32364.

    PMID: 36628047
  16. 16

    Deep vein thrombosis: update on diagnosis and management.

    Kruger PC, Eikelboom JW, Douketis JD, Hankey GJ

    The Medical journal of Australia 2019; (210(11)):516-524 doi:10.5694/mja2.50201.

    PMID: 31155730
  17. 17

    Venous thrombosis related to duplicated inferior vena cava: A case report and systematic review.

    Chen C, Huang DS, Chang KS, et al.

    Medicine 2025; (104(9)):e41748 doi:10.1097/MD.0000000000041748.

    PMID: 40020102
  18. 18

    Radiological evaluation of the natural history of PIK3CA-related overgrowth spectrum (PROS).

    Fraissenon A, Morin G, Boddaert N, et al.

    European journal of radiology 2026; (204()):113108 doi:10.1016/j.ejrad.2026.113108.

    PMID: 42520377
  19. 19

    Alpelisib for the treatment of PIK3CA-related head and neck lymphatic malformations and overgrowth.

    Wenger TL, Ganti S, Bull C, et al.

    Genetics in medicine : official journal of the American College of Medical Genetics 2022; (24(11)):2318-2328 doi:10.1016/j.gim.2022.07.026.

    PMID: 36066547

This page explains symptoms and warning signs associated with segmental progressive overgrowth and fibroadipose hyperplasia for informational purposes only and does not constitute medical advice. Seek emergency care for symptoms that may indicate a blood clot or limb emergency, and discuss individual risks with your clinician.

Guide contents Segmental progressive overgrowth syndrome with fibroadipose hyperplasia
Research & Literature
01 Understanding Your Diagnosis 03 Biology & Look-Alikes