A 2026 study of 136 melanoma patients found that a blood test combining vitamin B12 and inflammation markers predicted cancer recurrence, with higher scores associated with faster recurrence. However, Gram Research analysis shows the inflammation marker alone worked almost as well, suggesting the combination offers limited additional benefit over existing tests.
Researchers studied whether a simple blood test combining vitamin B12 and inflammation markers could predict which melanoma patients might have cancer return after surgery. In 136 patients followed for over 5 years, those with higher levels of this combined marker had shorter time before recurrence. However, Gram Research analysis found that the combination wasn’t significantly better than measuring inflammation alone. The findings are promising but need testing in larger groups before doctors can use this test in everyday care.
Key Statistics
A 2026 study of 136 melanoma patients found that 36% experienced cancer recurrence during a median 5-year follow-up, with those having higher B12/inflammation index scores experiencing recurrence significantly sooner than those with lower scores.
In the 2026 research of 136 melanoma patients, the combined B12/inflammation marker showed 65% sensitivity and 67% specificity for predicting recurrence, though inflammation alone demonstrated comparable predictive performance.
A 2026 analysis of 136 resected stage II-III melanoma patients found that patients with high B12/inflammation index scores were 2.39 times more likely to experience cancer recurrence compared to those with low scores after adjusting for other risk factors.
The Quick Take
- What they studied: Whether a blood test measuring vitamin B12 and inflammation together could predict if melanoma would come back after surgery.
- Who participated: 136 patients with stage II or III melanoma (moderate to advanced skin cancer) who had surgery to remove their tumors. Researchers tracked them for an average of 5 years.
- Key finding: Patients with higher combined B12/inflammation scores had cancer return sooner (63.5 months) compared to those with lower scores. However, the inflammation marker alone worked almost as well.
- What it means for you: This test might someday help doctors identify which melanoma patients need closer monitoring after surgery. However, it’s not ready for regular use yet and needs larger studies to confirm it actually helps patients.
The Research Details
This was a retrospective study, meaning researchers looked back at medical records of 136 melanoma patients who had already been treated. They measured vitamin B12 and C-reactive protein (a marker of inflammation) from blood samples taken before or around the time of surgery. They then tracked how long patients stayed cancer-free and used statistical methods to see if the blood test results predicted who would have recurrence.
The researchers tested different cutoff points for the combined blood marker to find which level best separated patients who would have recurrence from those who wouldn’t. They also compared the combined marker to each individual marker measured separately to see if combining them added value.
Finding better ways to predict which patients will have cancer return is important because it helps doctors decide who needs more aggressive monitoring or treatment. Currently, doctors use tumor stage and other physical characteristics, but these don’t tell the whole story. A simple blood test could be cheaper and easier than other tests, and it measures both metabolism and inflammation, two processes involved in cancer.
This study has some strengths: it followed patients for a reasonable length of time (median 5 years), used proper statistical methods, and adjusted for other factors that affect outcomes. However, it’s limited because it looked backward at existing records rather than following patients forward prospectively. The sample size of 136 is moderate. Most importantly, the authors themselves note this is exploratory research that needs validation in other patient groups before clinical use.
What the Results Show
During the study period, 49 of 136 patients (36%) experienced cancer recurrence. Using statistical analysis to find the best cutoff point, researchers identified a B12/inflammation index score of 3386 as optimal. Patients above this cutoff had cancer return much sooner (median 63.5 months) compared to those below the cutoff, whose cancer hadn’t returned even by the end of the study period.
When researchers adjusted for other known risk factors like tumor stage, the combined B12/inflammation marker remained significantly associated with recurrence risk. Specifically, patients with high scores were 2.39 times more likely to have recurrence compared to those with low scores.
However, when researchers compared the combined marker to its individual components, inflammation (C-reactive protein) alone was almost as predictive as the combination. Vitamin B12 by itself didn’t meaningfully predict recurrence.
Stage III disease (more advanced cancer) was also independently associated with shorter time to recurrence, with patients 2.37 times more likely to have recurrence. When researchers tested using the median score as a cutoff instead of the statistically optimized cutoff, the combined marker still predicted recurrence, though slightly less strongly. The inflammation marker and combined marker showed similar statistical performance in predicting outcomes.
This research builds on growing evidence that inflammation markers predict cancer outcomes. The finding that inflammation (C-reactive protein) is prognostically important aligns with previous research showing inflammation’s role in cancer progression. However, the finding that adding vitamin B12 doesn’t meaningfully improve prediction over inflammation alone is somewhat surprising and suggests that inflammation may be the primary driver of the association.
The study looked backward at existing records rather than following patients forward, which can introduce bias. The sample size of 136 is relatively small for this type of research. The study was conducted at a single center, so results may not apply to all populations. Most critically, the authors found no clear advantage of the combined marker over inflammation alone, limiting its practical value. The findings are exploratory and require validation in independent patient groups before clinical use.
The Bottom Line
This research is too preliminary for clinical recommendations. Patients with stage II-III melanoma should continue following their doctor’s standard monitoring protocols. While this blood test shows promise, it’s not ready for routine clinical use. Moderate confidence: inflammation markers may help identify higher-risk patients, but this needs confirmation in larger studies.
Melanoma patients and their doctors should be aware of this research direction, but it shouldn’t change current care. Researchers studying cancer prediction should note these findings. People with other cancers shouldn’t assume this applies to them. This research is most relevant to dermatologists and oncologists treating melanoma.
If this test eventually becomes clinically available, benefits would be seen immediately in terms of better risk stratification. However, the actual clinical benefit (whether closer monitoring improves outcomes) would take years to demonstrate.
Frequently Asked Questions
Can a blood test predict if my melanoma will come back?
A new blood test measuring vitamin B12 and inflammation together may help predict recurrence risk in melanoma patients. However, research shows the inflammation marker alone works almost as well, so this combination test isn’t yet recommended for routine clinical use.
What does the B12 and inflammation index score mean for melanoma patients?
Higher scores on this combined test were associated with faster cancer recurrence in a study of 136 patients. Patients with scores above 3386 had median recurrence at 63.5 months versus those below the cutoff who hadn’t recurred by study end.
Is this blood test better than current melanoma monitoring methods?
The research found this combined test wasn’t significantly better than measuring inflammation alone. While promising, it needs validation in larger patient groups before doctors can recommend it over current staging and monitoring approaches.
How often should melanoma patients get this blood test?
This test isn’t yet standard clinical practice. Melanoma patients should follow their oncologist’s recommended monitoring schedule, which typically includes regular physical exams and imaging based on cancer stage.
Does low vitamin B12 mean melanoma won’t come back?
Vitamin B12 alone didn’t predict recurrence in this study. The inflammation marker was the key predictor. Low B12 doesn’t guarantee cancer won’t return, and patients need comprehensive monitoring regardless of any single blood test result.
Want to Apply This Research?
- Track blood test results (vitamin B12 and C-reactive protein levels) at each oncology visit, noting the date and values. Record any signs of recurrence or new skin changes.
- Use the app to set reminders for scheduled follow-up appointments and skin self-examinations. Log any new moles, changes in existing moles, or concerning symptoms to discuss with your doctor.
- Maintain a timeline of all blood work and imaging results. Track patterns over time and share this history with your oncology team at each visit to help inform discussions about monitoring intensity.
This research is exploratory and not yet validated for clinical use. The findings should not change current melanoma monitoring or treatment decisions. Patients with melanoma should continue following their oncologist’s recommended surveillance protocols. This blood test is not currently recommended for routine clinical practice. Always consult with your dermatologist or oncologist about appropriate monitoring and any concerns about recurrence risk. This article is for educational purposes and should not be considered medical advice.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.