June 2026 Research Update

Across these studies, tuberous sclerosis complex (TSC) was most often identified through a combination of body imaging (especially brain, heart, and kidney scans) and genetic testing for changes in the TSC1 or TSC2 genes. The overall pattern was that imaging can show clear clues in multiple organs, while genetic testing can add clarity when imaging is normal or incomplete, or when the question is whether a condition is inherited. [1] [2] [3] [4]

In a retrospective study of 80 fetuses with heart rhabdomyomas (heart tumors), having multiple tumors and having a major brain change on fetal brain MRI helped predict which pregnancies involved TSC. Brain MRI changes were often not visible on ultrasound, and genetic testing of the fetus and parents (trio whole-exome sequencing) found a TSC gene change in some TSC-positive cases even when brain MRI looked normal. [1]

In a Chinese pediatric cohort of 112 children with TSC, imaging showed that organ involvement commonly clustered across brain, heart, and kidneys, with brain-heart and brain-heart-kidney patterns occurring most often. When comparing TSC1 versus TSC2, brain and heart imaging findings were similar, but TSC2 was linked to a higher risk of kidney angiomyolipomas and kidney cysts. [3]

In an observational cohort of 23 Egyptian patients with TSC, whole-exome sequencing identified many different TSC1/TSC2 variants, including several not previously reported, and most were unique to a single family. Genetic testing found a disease-causing or likely disease-causing variant in 20 of 23 patients, while three had a gene change of uncertain meaning, highlighting that genetic results can sometimes be hard to interpret without more evidence. [2]

A separate prospective study focused on people with kidney tumors (not limited to TSC) and tested a short risk score to identify who might have an inherited kidney tumor syndrome and should be referred for genetic testing. Among those tested, inherited conditions were found in about half, and most of these were TSC; signs outside the kidney and having tumors in both kidneys or multiple tumors were the strongest predictors of an inherited cause. [4]

For patients and caregivers, this set of studies reinforces that TSC is often recognized by putting together information from different types of tests rather than relying on one test alone. These papers are most relevant as background for understanding why clinicians may look at multiple organs (such as brain, heart, and kidneys) and why genetic testing may be considered even when some scans look normal, especially in prenatal settings or when kidney tumors raise questions about an inherited syndrome. What remains uncertain is how well some tools (like the kidney tumor risk score) work outside the single center where they were developed, and how often gene changes of uncertain meaning can be clarified in routine care. [1] [2] [3] [4]

Across these papers, kidney involvement in tuberous sclerosis complex (TSC) mainly centered on renal angiomyolipomas (AMLs), which can sometimes bleed, and less commonly on kidney cancer. One larger retrospective study suggested that certain imaging and clinical features can help estimate the chance of AML rupture, while two single-patient reports showed very different kidney tumor situations with preserved kidney function after surgery. [5] [6] [7]

In a retrospective study of 379 people with renal AML, TSC status, tumor size 4 cm or larger, outward-growing (exophytic) shape, and rich blood supply were each linked to higher rupture risk, and a prediction tool built from these factors had strong performance in the validation group (AUC 0.967). [5]

The same AML study also reported tissue and blood-marker differences between hemorrhagic and non-hemorrhagic AMLs: higher CD34 and PPARG and lower PTEN in hemorrhagic cases, which the authors suggested may relate to fragile blood vessels within the tumor. This was not proof of cause, but it adds clues about why some AMLs might bleed. [5]

Two case reports showed that kidney tumors in TSC are not always limited to AML. One 15-year-old girl had a papillary renal cell carcinoma confirmed after removal of the affected kidney, and she remained asymptomatic with preserved kidney function during follow-up. [6]

Another case report described a 59-year-old woman whose TSC was diagnosed in adulthood after she was found to have bilateral AMLs and typical skin findings. She had kidney-sparing surgery for a larger AML, then started sirolimus to help limit growth of remaining AMLs, and her kidney function remained preserved at follow-up. [7]

For patients and caregivers, these papers reinforce that kidney risks in TSC can include both AML bleeding and, more rarely, kidney cancer, and that imaging details (size, growth pattern, blood supply) may help clinicians estimate bleeding risk. The rupture prediction tool and the molecular signals are early-to-moderate evidence and need confirmation in other settings, while the cancer and adult-diagnosis reports describe single people and may not reflect most patients. Together, this is mainly background information to understand why kidney imaging and multidisciplinary follow-up are commonly discussed in TSC care.

This month, the clearest pattern was that different TSC-related lung problems can look similar on imaging but behave differently over time. In adults with lymphangioleiomyomatosis (LAM), longer-term real-world data linked sirolimus to stable or slightly improved breathing tests and improvement in some related lymphatic and kidney growths, with mostly mild side effects. In contrast, multifocal micronodular pneumocyte hyperplasia (MMPH) was described as multiple hazy lung nodules that were sometimes mistaken for early lung cancer during surgery, yet follow-up outcomes were generally favorable. [8] [9]

In a 71-person retrospective cohort of adults with LAM (including TSC-associated LAM), lung function was stable overall, with a small median rise in one breathing test at 12 months, and gas transfer generally staying steady over time. Fluid problems related to the lymphatic system (chylous effusions) resolved by 12 months in those who had them, and imaging-based size measures of certain kidney and lymphatic growths decreased in patients who had paired scans. A blood marker (VEGF-D) was higher at baseline in people with lymphatic involvement and fell during treatment, supporting its role as a monitoring marker in this setting. [8]

A single case report of a 36-year-old woman with TSC-associated LAM described three years of trough-guided sirolimus monitoring with clinical stability, no major side effects, no cyst progression on lung imaging, and a reduction in kidney angiomyolipoma volume. Because this is one person, it shows what is possible in an individualized care plan but cannot predict what will happen for others. [10]

For MMPH, an eight-patient retrospective series described multiple ground-glass lung nodules on CT scans and found that most tested cases had a TSC1 gene change; one had a TSC2 change plus a BRAF change. Several patients had their nodules removed surgically, and frozen-section testing during surgery was misread as early lung adenocarcinoma in multiple cases, highlighting how MMPH can mimic cancer in the moment. Follow-up (median 14 months) was described as favorable in this small group. [9]

One exploratory lab and animal study looked for biological clues that might help track or understand LAM over time. Using single-cell methods in a mouse TSC model and checking human LAM samples, the authors described a tumor cell subgroup with neural crest-like features and reported changes in several blood proteins (higher SPP1 and KRT18 in some patients and lower LCN2 in nearly all), alongside changes in VEGF-D. These results suggest possible future blood markers beyond VEGF-D, but they are not yet established for routine patient monitoring. [11]

For patients and caregivers, these papers reinforce that TSC can involve more than one type of lung change, and that monitoring may rely on a mix of breathing tests, imaging, and sometimes blood markers depending on the lung condition. The strongest human evidence in this set comes from a single-center real-world LAM cohort suggesting stability of lung measures during sirolimus use, while MMPH reports mainly matter as background for understanding why certain CT scan patterns can be confusing even to experts. The lab study is early-stage and mainly points to possible future blood tests; it does not yet change how lung monitoring is typically done. [8] [9] [11]

Across these studies, neuropsychiatric challenges and sleep problems were common parts of life with tuberous sclerosis complex (TSC). Patterns included frequent mood and attention symptoms, language and learning difficulties, and high rates of poor sleep in adults, with some differences by age and by which TSC gene was involved. [12] [13]

In a cross-sectional study of 311 people with TSC in China using a Chinese version of the TSC-associated neuropsychiatric disorders checklist, people averaged eight behavioral concerns, with mood swings, language impairment or delay, and inattention reported most often. Among 152 people who had IQ testing, 68.4% had intellectual disability, and autism spectrum disorder was reported in 22.2%. [12]

The same study reported that school-aged children commonly had academic difficulties, especially in mathematics, while adults more often had anxiety and depression. It also found differences in neuropsychiatric features between people with TSC1 and TSC2 gene changes, with TSC2 linked to more severe neuropsychiatric profiles. [12]

In a separate cross-sectional study of 84 adults with TSC, 64% met criteria for poor sleep on a standard sleep questionnaire. Poor sleep was more common in those reported to have mental illness or anxiety, and it was also linked with use of mTOR inhibitors, antidepressants, and anti-seizure medicines in this cohort. [13]

One animal study explored a possible future approach for TSC-related thinking and anxiety symptoms by testing J4, a compound that blocks ENT1 and can raise adenosine outside cells. In male Tsc2+/- mice, 10 weeks of J4 improved performance on a memory task and reduced anxiety-like behavior, alongside brain imaging and tissue measures suggesting improved white-matter and myelin features. [14]

For patients and caregivers, this set of papers reinforces that mood, attention, language and learning challenges, and sleep quality can be central day-to-day issues in TSC, and that these concerns may look different across childhood versus adulthood. The human studies describe how common these experiences were in the specific groups studied, while the mouse study is early-stage research that helps scientists test ideas about brain pathways that could relate to thinking and anxiety symptoms, but it does not show what will happen in people. Important uncertainties include how widely these prevalence estimates apply across countries and care settings, and whether the medication links with sleep reflect the drugs themselves, the conditions they are used for, or other factors not captured in cross-sectional research. [12] [13] [14]

Across these papers, the main pattern is that tuberous sclerosis complex (TSC) can involve uncommon heart and blood vessel problems that may be found on imaging and may require specialized care. The evidence is limited because one paper is a single-patient report and the other combines a small surgical series with a broader literature review, so it cannot define how often these issues happen in TSC. [15] [16]

One case report described a 9-year-old boy with TSC who had a cardiac rhabdomyoma (a heart tumor seen in some children with TSC) and a rare structural change called a double-chambered left ventricle, where a band-like structure divided the main pumping chamber. The authors also reported a new (de novo) nonsense genetic variant (c.2497C>T, p.Q833X) and proposed that the rhabdomyoma could have physically influenced heart development, contributing to the chamber being subdivided. [15]

A separate report described surgical treatment for abdominal aortoiliac aneurysms (bulges in the main belly artery and nearby branches) in five children at one center, and summarized 96 additional pediatric cases from the literature. In the center's five patients, there were no deaths around the time of surgery, and four had stable outcomes without aneurysm recurrence or reduced blood flow problems over a median 5-year follow-up. [16]

In that same surgical series, one child with TSC died 5 years after surgery due to seizure-related causes rather than a reported aneurysm complication, and one patient had an early graft clot but remained without symptoms because other blood vessels provided alternate blood flow. These details suggest that longer-term outcomes can be influenced by both surgical issues and the child's other medical conditions. [16]

For patients and caregivers, these papers mainly serve as background on the range of heart and blood vessel issues that can occur in childhood, including rare heart structure differences and rare large-artery aneurysms. The single-patient heart report cannot show how common the combination is, and the aneurysm surgery paper includes only one patient with TSC in its center experience, so it cannot estimate TSC-specific risks. What remains uncertain is how often these problems occur in TSC and which factors (genetics, tumor location, growth patterns) most strongly relate to later heart or blood vessel changes.

This month, the strongest patient-focused pattern was that tuberous sclerosis complex (TSC) can include body findings beyond the brain, including teeth, soft tissue lumps, bones, and pelvic organs. The evidence ranged from a systematic review of dental changes to single-patient reports and lab studies that help explain how certain growths may form. [17] [18] [19]

A systematic review and meta-analysis of seven studies (217 people with TSC) estimated that about two-thirds had enamel pits, although results varied a lot depending on how teeth were examined and which teeth were assessed. The authors also proposed a more "phenotype-oriented" way to describe enamel changes so dental features in TSC can be reported more consistently across studies. [17]

One report described a child with a TSC1 gene change who developed a lipoma (a fatty lump). Testing of the lump showed loss of the remaining working copy of TSC1 in that tissue and increased activity in the mTOR pathway, and cell experiments showed that reducing TSC1 increased fat-cell precursor growth. This was an exploratory, lab-based study and cannot show how often lipomas happen in TSC or how they behave in most people. [18]

A separate single-patient report described a woman in her 20s with TSC who had a large ovarian endometrioma that was initially mistaken for metastatic disease based on CT and a bone scan. The clinicians ultimately interpreted bone scan changes as sclerotic bone lesions that can be seen in TSC, and the ovarian lesion remained stable on short follow-up after she declined surgery. Because this describes one person, it may not apply to others with TSC. [19]

For patients and caregivers, these studies add detail about the range of non-brain features that can occur in TSC, especially dental enamel changes, and they illustrate how some imaging or tissue findings can be confusing without TSC-specific context. The dental review is the most generalizable evidence here, while the lipoma and ovarian endometrioma reports mainly provide background about what has been seen in individual patients and what scientists are learning in the lab. It remains uncertain how common TSC-related lipomas are, which people are most likely to develop them, and how often pelvic findings like endometriomas are mistaken for other conditions on imaging. [17] [18] [19]

Two papers focused on what TSC-related proteins (TSC1 and TSC2) do in cells, rather than on typical clinical TSC features. One was lab research on how cells handle stress, and the other was a small clinical study in bladder cancer that used a TSC-1 tissue marker to estimate recurrence risk. These do not directly describe common day-to-day TSC symptoms, but they add context on where TSC pathways show up in other areas of medicine. [20] [21]

In lab models, researchers identified TSC2 as a regulator of stress granules, which are temporary clusters of proteins and RNA that form when cells are under stress. In mouse cells missing TSC2, stress granules formed spontaneously in a way linked to mTORC1 activity and protein-translation changes, while human cells did not show this spontaneous effect, even with near-complete TSC2 loss. Fibroblasts from people with partial TSC2 loss showed largely normal stress-granule responses, including normal disassembly after stress; the slower disassembly was seen only in mouse cells with complete TSC2 loss. [20]

In a retrospective study of 40 people with low-risk non-muscle invasive bladder cancer treated with surgery, tumor staining for TSC-1 was linked to higher odds of cancer recurrence during follow-up, while CD44 staining was more common in people without recurrence. This study looked at bladder tumors, not at TSC as a condition, and it does not mean that people with TSC have bladder cancer or should expect recurrence. [21]

For most families affected by TSC, these studies are mainly background science: they help explain how the TSC pathway can influence cell behavior under stress and how TSC-related markers can be used in other diseases. The cell-stress work is preclinical and cannot yet tell whether stress-granule changes drive specific symptoms in people with TSC, or whether they could become a useful biomarker. The bladder cancer marker study is small and not TSC-focused, so its relevance to TSC care is uncertain. [20] [21]